Article

Integrated control of postharvest blue mold decay of pears with hot water treatment and Rhodotorula glutinis

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Abstract

The potential of using Rhodotorula glutinis alone or in combination with hot water for the control of postharvest blue mold decay of pear fruit, and their effects on postharvest quality of fruit was investigated. Spore germination of Penicillium expansum was inhibited by hot (46 °C) water. Both hot water for 10–20 min and R. glutinis, as stand-alone treatments, reduced the incidence of blue mold decay, but complete control was not achieved by either treatment. However, a combination of hot water treatment and R. glutinis completely controlled decay of inoculated fruit. In addition, the combination of hot water treatment with R. glutinis on naturally infected, intact fruit, reduced decay from 66.7% in the control fruit to 13.3% after 15 days at 20 °C, and from 46.7 to 6.7% after 4 °C for 60 days followed by 20 °C for 15 days. None of the treatments impaired fruit quality. The combination of hot water and R. glutinis could be an alternative to synthetic fungicides for the control of postharvest blue mold decay on pears.

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... In the isolation of the target yeast, 8g nutrient broth, 5g yeast extract, 10g glucose and 20g agar in a litre of distilled water was used and incubated at 28 o C for 20hrs. In a similar experiment by Zhang et al (2008) the antagonistic Rhodotorula glutinis was isolated from the surfaces of strawberries harvested in an unsprayed orchard and identified by the VITEK 32 Automicrobeic system by a France company bioMérieux for the control of blue mold in pears. In another research, Manso and Nunes (2011) isolated epiphytic microorganisms from the surfaces of leaves from pome and citrus fruit picked from different orchards. ...
... Zhang et al (2009) investigated the effects of R. glutinis on postharvest quality parameters of apples and reported no significant differences in mass loss, firmness, total soluble solids (TSS), ascorbic acid (AA), and titratable acidity (TA) when the apple fruits were stored at 20 o C for 5 days or at 4 o C for 30 days followed by 20 o C for 4 days. In pears, no significant differences in quality was observed by Zhang et al (2008) when they studied the effect of combined hot water treatment and antagonistic R. glutinis on pears mass loss, fruits firmness, TSS, AA and TA, whether the pears were stored at 20 o C for 15 days or at 4 o C for 60 days followed by 20 o C for 15 days. These results were similar to another study by Zhang et al (2008) on peach using antagonistic yeast with salicylic acid on the quality of stored products. ...
... In pears, no significant differences in quality was observed by Zhang et al (2008) when they studied the effect of combined hot water treatment and antagonistic R. glutinis on pears mass loss, fruits firmness, TSS, AA and TA, whether the pears were stored at 20 o C for 15 days or at 4 o C for 60 days followed by 20 o C for 15 days. These results were similar to another study by Zhang et al (2008) on peach using antagonistic yeast with salicylic acid on the quality of stored products. They reported no significant reduction in weight loss, fruit firmness, TSS, AA or TA when the peach was stored at 20 o C for 7 days. ...
... Yield losses due to FHB rank second after leaf rust and are particularly high in Canada, China, the US Midwest, Paraguay, southern Brazil, Uruguay, and Argentina. . For example, FHB caused 30-70% yield losses in Argentina in 2012 (Palazzini et al. 2015;Laraba et al. 2017), 11.6-39.8% of yield losses between 2000-2010 in Brazil (Reis & Carmona 2013), and 10-70% of yield losses have been reported in China (Zhang et al. 2011;Yun et al. 2019). Wheat grains infected by Fusarium spp. ...
... Fhb7 is located on wheat chromosome 7DS which was derived from the alien species called Thinopyrum ponticum. Fhb7 is a stable gene and it has a major QTL with a major effect on the FHB resistance (Zhang et al. 2011) which was located on 7LL (7DS) and 7EL2 (7D) by the e-chromosome substitution system of the Thinopyrum elongatum. Guo et al. (2015) located the gene within the range of markers Xsdauk66 and Xcfa240, with the genetic distance between the markers being 1.7 cM. ...
Article
Full-text available
Fusarium head blight (FHB), mainly caused by Fusarium graminearum, is one of the most devastating diseases of wheat globally. FHB causes an extensive reduction in yield and reduces the grain quality through its contamination with Fusarium toxins such as deoxynivalenol (DON), T2 toxin, HT-2 toxin, nivalenol, and zearalenone. This review provides an overview of updated progress of genetic studies on the resistance to FHB, with an emphasis on the sources of resistance to FHB, resistance gene/quantitative trait loci (QTL) mining, resistance gene cloning, major FHB resistance genes/QTL identification by molecular markers, and resistance mechanisms. The achievements of resistance breeding based on phenotype selection and molecular markers was also summarised. Based on the systematic analysis of breeding limitations and utilisation of FHB resistant materials, the authors put forward three suggestions: First, to toughen the resistance identification of wheat, testing traits such as Fusarium damaged kernel and DON need special attention as visual symptoms are less reliable, resistant varieties should be popularised, and the screening the resistant genes should be strengthened; The second is to use the additive effect of quantitative resistance genes accumulated from existing varieties to reduce the cost of resistance in order to create high yielding resistant varieties. Thirdly, to enhance research and utilization of new genes. Keywords: breeding strategy; QTL mapping; resistance gene; resistance mechanisms; wheat scab
... Kako tretiranje plodova fungicidima nakon berbe u europskim zemljama nije dopuńteno, u novije se vrijeme uvode ekolońki prihvatljivi tretmani (npr. toplinski tretmani uz uporabu etanola ili bez njega, uporaba antagonistiţkih kvasaca i sl.) koji bi zańtitili plod od nastanka ozljeda 838 od niske temperature tijekom ţuvanja i istodobno smanjili gubitke izazvane fitopatogenim gljivama (Margosan i sur., 1997.; Zhang i sur., 2008.). Toplinski se tretmani, kao i na drugim vošnim vrstama (Jemriš i sur., 2003.; 2006.) ...
... Ta je tehnologija u kombinaciji s antagonistiţkim kvascem Rhodotorula glutinis bila uspjeńna u suzbijanju Penicillium sp. na kruńki (Zhang i sur., 2008.). Svrha ovoga rada bila je istraņiti mogušnost uporabe toplinskih tretmana u suzbijanju bolesti plodova nektarine tijekom ţuvanja. ...
... The situation is different e , in humans, especially after the discovery of yeasts which could be added to their food in order to maintain their health by contributing in fighting toxicants and illness (Koleva et al., 2008). Recently, an antagonistic yeast strain of Rhodotorula glutinis have been reported as an effective biocontrol agent (in vivo) against postharvest decay of fruits and vegetables (Qin et al., 2003;Zhang et al., 2007;Zhang et al., 2008;Malisorn and Suntornsuk, 2008). Moreover, the yeast strain of Rhodotorula glutinis and its autoploidy have been reported as an effective biocontrol agent (in vivo) and (in vivo) against grey mould of greenhouse sweet pepper (Haggag, et al., 2005). ...
... Furthermore, in another studies (in vitro) an antagonistic yeast strain of Rhodotorula glutinis has been reported as an effective biocontrol agent against post-harvest decay of apples (Qin et al., 2003), pears (Zhang et al., 2008;Zhang et al., 2009), strawberries (Zhang et al., 2007), sweet cherries (Tian et al., 2004) and oranges (Zhang et al., 2005). Also, an antagonistic yeast strain of Rhodotorula glutinis and its autoploidy have been reported as an effective biocontrol agent (in vitro) and (in vitro) against grey mould of greenhouse sweet pepper (Haggag, et al., 2005). ...
... As a secure and non-chemical method, postharvest heat treatment has been investigated to control fruit fly infestation and disease, and induce resistance to injury sustained from chilling (Ghasemnezhad et al., 2008;Lurie, 1998). Moreover, heat treatment has been reported to enhance the biocontrol effectiveness of antagonistic yeasts against Penicillium expansum in pear (Zhang et al., 2008), Botrytis cinerea in tomato (Zong et al., 2010), Colletotrichum acutatum in loquat fruit , and Rhizopus stolonifer in peach (Zhang et al., 2007). However, the mechanisms by which heat treatment enhances biocontrol efficacy of antagonists are still not fully understood. ...
... The effects of P. membranaefaciens, HWT, or their combination on the natural infection of citrus fruits were evaluated according to the method of Zhang et al. (2008) with some modifications. Intact fruits were divided into six groups. ...
... Microbial biocontrol agents have shown a great potential as an alternative to synthetic fungicides for the control of postharvest decay of fruits and vegetables (Wilson et al., 1991). Recently, an antagonistic yeast strain of Rhodotorula glutinis have been reported as an effective biocontrol agent against postharvest decay of apples (Qin, Tian, Liu, & Xu, 2003), pears (Zhang, Wang, Huang, Dong, & Zheng, 2008), strawberries (Zhang et al., 2007), sweet cherries (Tian, Qin, & Xu, 2004) and oranges (Zheng, Zhang, & Sun, 2005). It has been reported that biological control is only effective with high concentrations of antagonistic yeasts (Fan & Tian, 2001). ...
... The probe descended toward the sample at 1.0 mm s À1 , and the distance that the probe travelled through the sample is 10 mm. The maximum force (N) was defined as firmness (Zhang et al., 2008). ...
Article
The effect of Rhodotorula glutinis treatment alone or in combination with methyl jasmonate (MeJA) in controlling blue mold decay, the natural fungal decay of pears and the postharvest quality parameters including fruit firmness, total soluble solids, titratable acidity, and ascorbic acid were investigated. The combination of methyl jasmonate (200 μM) and R. glutinis (1 × 108 CFU/ml) was a more effective approach to reduce the disease incidence and lesion diameter of blue mold decay of pears than the application of MeJA or R. glutinis alone after incubation for 7 d at 20 °C. The natural fungal decay of pears treated with the application of R. glutinis combined with MeJA resulted in reduced average decay incidence of 10.42% or 4.16%, respectively, compared with 27.17% or 20.83% in the control fruits following storage at 20 °C for 15 d or 4 °C for 60 d followed by 20 °C for 15 d. The combined treatment did not impair quality parameters of fruits under both conditions.
... Currently, the use of chemical agents remains the major method of choice by far for managing postharvest rots and the few postharvest biocontrol products that are commercially available have limited use, mostly in niche markets. A survey of the literature also indicates that most researchers are using strains of a surprisingly limited number of yeast or bacterial species and most research has been limited to studying a new strain on a new commodity and/or perhaps against a new disease (Goyal and Spotts, 1997; Korsten et al., 1997; Leibinger et al., 1997; Teixido et al., 1998; Lima et al., 1999; El Ghaouth et al., 2000; Ippolito and Nigro, 2000; Janisiewicz et al., 2001; Jiang et al., 2001; Saligkarias et al., 2002; Karabulut et al., 2004; Larena et al., 2005; Zheng et al., 2005; Zhang et al., 2006 Zhang et al., , 2008 Guijaro et al., 2007; Sugar and Basile, 2008). It seems that the last 5 years have seen a tremendous amount of " reinventing the wheel " and little progress has been made towards wider commercial implementation of effective and economically viable biocontrol products. ...
... Results of tests performed under commercial or semicommercial conditions with formulated biocontrol preparations indicate that inconsistency and variability in the level of disease control are among the most significant barriers preventing widespread implementation of biocontrol technology. In order to improve reliability and efficacy, efforts have been made to enhance efficacy and reliability by various means that include the addition of salts and organic acids (Droby et al., 1997; Karabulut et al., 2001), glucose analogs (El Ghaouth et al., 2000 ), food additives (Droby et al., 2002b; Karabulut et al., 2003; Qin et al., 2006) and integration with physical treatments (Porat et al., 2002; Zhang et al., 2006 Zhang et al., , 2008). Although promising additive and synergistic effects have been obtained, critical information on the interactions between antagonists, complementary treatments, pathogens, and commodities is still lacking. ...
Article
The use of biocontrol agents as an alternative to synthetic, chemical fungicides that are presently used to control postharvest pathogens, has many constraints and obstacles that make it difficult to implement their use as a practical control strategy. Over the last 20 years postharvest biocontrol research has evolved towards being more integrated into a production systems approach with greater awareness of industry concerns. More research, however, is needed in many aspects of the science and technology of postharvest biocontrol and in integrating biocontrol agents into combined pre- and postharvest production and handling systems. Better understanding of the mode of action of postharvest biocontrol agents, relationships between infection levels occurring in the field and development of postharvest decay, along with basic information on microbial ecology and survival mechanisms of biocontrol agents on fruit surfaces, is critical for the advancement of successful implementation of postharvest biocontrol technology. The past 20 years of postharvest biocontrol research has seen tremendous advances and the creation of several products. Nonetheless, numerous challenges and opportunities still exist as this field of research matures. This review is an attempt to examine the field of postharvest biocontrol as it has developed over the past 20 years, define the reasons that have limited its commercialization, and identify areas of research that need to be addressed if the potential of postharvest biocontrol is to be achieved. We have also introduced a new paradigm for biocontrol research that may provide new opportunities for increasing the efficacy and consistency of biocontrol products.
... The effective use of other HWT methods such as hot water dipping and hot water rinse brushing is also demonstrated in the successful management of post-harvest penicillium spoilage occurring in the pear, orange, lemons, grapefruits, and tangerine. [252][253][254] Usually, improperly hot water treated fresh commodities can experience internal and external injuries including symptoms of as skin browning, pitting, colored spots, and browning. [255] Hot air treatment employs longer exposure (several hours or days) of fruits in a heated air atmosphere having temperature and RH of more than 30°C and 90%, respectively. ...
Article
Post-harvest commodities wastage due to decay caused by the pathogenic fungi generates a huge amount of economic losses worldwide. Different species of Penicillium spoil various foodstuffs and produce mycotoxins, alkaloids and other harmful cellular metabolites in the food. Presently, synthetic fungicides, mainly used for fungal diseases control, are associated with harmful impacts on the environment and consumer health. Hence, non-fungicide based eco-friendly and commercially viable alternative is proposed for ensuring food safety. In recent years, the safer options that have been explored include microbe mediated biological control, botanical pesticides, use of generally regarded as safe (GRAS) compounds, and innovative physical approaches including cold plasma, and pulsed light techniques. These emerging technologies could be utilized in the multiple hurdle concept of disease management for suppressing pathogens growth at different stages of spoilage development. This review, first of its kind, summarizes the exclusive information on Penicillium spp. induced spoilage, associated toxicological concerns and the potential of non-fungicide-based promising approaches for managing fungal wastage in the harvested horticultural commodities.
... The control of blue mould (Penicillium expansum) in pome fruit has been significantly improved with the application of combined treatments, while storing at low temperatures . In the first instance, application of a short warm water (46°C) treatment, followed by the surface inoculation with a yeast antagonist (Rhodotorula glutinis) has been shown to synergistically control blue mould in Nashi pears (Zhang et al. 2008). In that example, fruit were held in cold air storage conditions. ...
Chapter
The use of combined treatments to manage fruit and vegetable quality has been successfully applied in commercial practice, particularly for apples. This historical success is well documented. Unfortunately, the extensive use of combined treatments has not been adopted as a general principle to optimize produce quality, shelf life and safety. The thesis of this review is to discuss the basis for the effectiveness of combined treatment approaches and also discuss potential combined treatments that could significantly improve quality, shelf life and safety of a wide range of fruit and vegetable products. The use of molecular tools in the evaluation of synergistic physiological responses to combined treatments is also discussed.
... Recently, an antagonisticyeast strain of Rhodotorula glutinis have been reported as an effective biocontrol agent against postharvest decay of apples [16], pears [20], strawberries [21] and oranges [22]. ...
... Em maçãs 'Fuji', o tratamento dos frutos por aspersão de água aquecida a 53ºC durante 30 segundos proporcionou eficiente controle de Botryosphaeria dothidea (OSTER, 2004). Zhang et al. (2008) utilizaram o tratamento hidrotérmico associado com Rhodotorula glutinis para o controle in vitro e in vivo de Penicillium expansum em pêras e constataram a inibição da germinação dos esporos em todos os tempos de exposição (5, 10, 15 e 20 minutos) a 46 °C, sendo que frutos tratados termicamente a 46 °C / 15 minutos apresentaram menor incidência de bolor azul quando comparados ao controle. Além de atuar diretamente no controle de podridões, o tratamento térmico pode induzir respostas de defesa em frutos, por meio da indução da síntese de compostos como fitoalexinas ou proteínas relacionadas à patogênese (LURIE, 1998). ...
Article
Full-text available
The aim of this review is to analyze the main methods of physical control (ultraviolet C radiation - UV-C, gamma radiation, refrigeration, modified atmosphere and heat treatment) of postharvest diseases in fruits and vegetables. The use of pesticides is still the main measure to control postharvest decay. O objetivo desta revisão é analisar os principais métodos de físicos de controle (radiação ultravioleta C, radiação gama, refrigeração, modificação da atmosfera e tratamento térmico) de doenças pós-colheita de frutas e hortaliças, visto que a utilização de agrotóxicos ainda é a principal medida para o controle de podridões pós-colheita.
... These results confirmed previous studies where germination of B. cinerea spores was reduced by a HWT of 43°C for 10-30 min (Zhao et al. 2014), and a HWT of 35-50°C for 30 s (Gabler et al. 2004). The germination of P. expansum spores was reduced by a hot water pressure treatment of 40°C for 5 to 60 min , and a HWT of 46°C for 5 to 20 min (Zhang et al. 2008). HWT has also been reported to inhibit the in vitro growth of other fungal pathogens, including Fusarium oxysporum (Sui et al. 2014), Neonectria galligena (Maxin et al. 2012b), Colletotrichum gloeosporioides (Alvindia and Acda 2015), Monilinia fructicola, Monilinia laxa, and Monilinia fructigena (Jemric et al. 2011;Spadoni et al. 2013Spadoni et al. , 2014. ...
Article
Full-text available
Hot water treatment (HWT) of fruit is an effective approach for managing postharvest decay of fruits and vegetables. In the present study, the effects of HWT (45 °C for 10 min) on the growth of Botrytis cinerea and Penicillium expansum in vitro, and gray (B. cinerea) and blue mold (P. expansum) development in kiwifruit were investigated. HWT effectively inhibited spore germination and germ tube elongation of B. cinerea and P. expansum. Reactive oxygen species accumulation and protein impairment in the fungi triggered by HWT contributed to the inhibitory effect. Results of in vivo studies showed that HWT controlled gray and blue mold in kiwifruit stored at 4 and 25 °C. HWT induced a significant increase in the activity of antioxidant enzymes, including catalase and peroxidase, and the level of total phenolic compounds in kiwifruit. These findings indicate that the inhibition of postharvest decay in kiwifruit by HWT is associated with the inhibition of spore germination of both fungal pathogens and the elicitation of defense response in the kiwifruit host. Moreover, HWT used in this study did not impair fruit quality. HWT appears to represent a potential non-chemical alternative for the effective management of postharvest decay of kiwifruit.
... P. anomala is an efficient agent for the biological control of fungi of agricultural importance (Walker 2011), such as B. cinerea and Penicillium spp. in apple (Haissam 2011) and other fungi and Enterobacteriaceae present in cereal grains (Olstorpe et al. 2012). The use of R. glutinis as an efficient biological control agent in postharvest diseases of apples (Qin et al. 2003), pears (Zhang et al. 2008) and other fruits, and the use of Rhodotorula sp. (Rh1) in the control of soft rot in Chinese cabbage (Mello et al. 2011) have been previously reported. ...
Article
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Bacterial fruit blotch (BFB), caused by Acidovorax citrulli, is the most important bacterial disease affecting melon plants in Brazil. The aim of the present study was to analyze the efficacy of yeasts for the biological control of BFB, applied by spraying to protect seedlings, foliage and fruits, and as a seed treatment. Additionally, the in vitro activity of the yeasts and plant growth promotion were evaluated. Among 60 strains, LMA1 (Rhodotorula aurantiaca), CC-2 (Pichia anomala) and LMS (Rhodotorula glutinis) were the most efficient for seedling protection. Among the three selected strains, only LMA1 and CC-2 maintained efficacy when tested on foliage and seeds, with reductions in the disease index and area under the disease progress curve of 58.6 and 47.2 %, respectively. Furthermore, LMA1 and LMS protected fruits. In vitro, neither of the strains inhibited bacterial growth, produced killer toxins, or showed competition for nutrients with the pathogen. None of the three yeasts promoted the growth of melon plants. Therefore, these yeasts have potential for BFB biocontrol in different disease stages and may be used in the integrated management of BFP.
... it could control the activity of pectinmethylesterase and polygalacturonase (Chávez-Sánchez et al., 2013). Treatment of this type associated with Rhodotorula glutinis was shown to reduce blue mold (Penicillium espansum) in pears, where fruits treated for 15 min for 46°C showed a lower incidence of this disease (Zhang et al., 2008). Hydrothermal treatments can delay ripening in mango (Yimyong et al., 2011) and reduce the incidence of fruit fly in litchie and longan (Armstrong and Follett, 2007). ...
Article
Full-text available
The control of anthracnose (Colletotrichum simmondsii) during the post-harvest stage in guava fruits (Psidium guajava L.) was performed by the application of phosphites [phosphite-K (40% P2O5 and 30% K2O) and phosphite-Ca (10.7% P2O5, 3.89% Ca, and 0.5% B)] including the Carbendazim as reference, calcium chloride (CaCl2), acetyl salicylic acid (ASA), hot water (HW), and 1-methylcyclopropene (1-MCP). These treatments were applied individually or in combination each other with two or three compounds. The evaluated parameters were diameter of anthracnose lesion (DL), number of lesions (NL), and fruit quality (fresh weight loss, pH, total soluble solids, and titrable acidity]. The fruits were disinfested, inoculated, and maintained in an incubator containing fluorescent lights at 75 μmol·m-2 ·s-1 (25°C, 12h photoperiod) for 5 days and were then analyzed. The results showed that the DL and the NL were reduced following treatments, and that the HW (47°C for 20 min) was the strongest and the 1-MCP treatment was the least effective. The physico-chemical characteristics of fruits were affected by some treatments without compromising fruit quality. The combination of treatments was also able to alleviate the anthracnose effect on fruits compared to individual treatments and the control without affect the fruit quality. The combinations which included the HW treatment showed the best performance to control this disease, particularly when combined with the 1-MCP and phosphite.
... The effective use of other HWT methods such as hot water dipping and hot water rinse brushing is also demonstrated in the successful management of post-harvest penicillium spoilage occurring in the pear, orange, lemons, grapefruits, and tangerine. [252][253][254] Usually, improperly hot water treated fresh commodities can experience internal and external injuries including symptoms of as skin browning, pitting, colored spots, and browning. [255] Hot air treatment employs longer exposure (several hours or days) of fruits in a heated air atmosphere having temperature and RH of more than 30°C and 90%, respectively. ...
Chapter
The multitasked Nitric oxide (NO) is a highly reactive, gaseous molecule that is endogenously produced in the plant cells through various routes. In the plant, NO participates in numerous physiological processes including growth and development as well as adaptation against (a)biotic stresses. At the molecular level, NO acts as a redox-related signaling molecule whose function entirely depends on two factors (concentration and spatial generation pattern). Once generated, it directly or indirectly interacts with other redox-related molecules (O2−, H2O2, H2S, NO2−) and potentially interacts with various biomolecules including proteins, lipids, hormones, and nucleic acid at the downstream level. The variety of NO acting mechanisms include direct reaction with redox molecule, metal-nitrosation of transient metals, protein tyrosine nitration, and S-nitrosation. Since the discovery of the physiological role of NO in plants, numerous studies have been conducted to elucidate the production pathways, mechanism of action, and its ultimate effect in distinct physiological processes. However, over time, some questions still remain unanswered, and with new knowledge on interactions of NO with fatty acids and nucleic acids, more possible regulatory roles of NO in mitigation of stresses is still under investigation. Therefore, this chapter discusses the NO production, mechanism of action, and role in the regulation of plant’s (a)biotic stress response.
... Hot water treatment is one of the most promising non-fungicide technologies and quarantine treatment for controlling postharvest diseases. Hot water treatment can be applied effectively to suppress certain important postharvest pathogens in a number of fruits, such as Penicillium expansum on pears (Zhang et al., 2008), Penicillium digitatum Sacc. on lemon fruits (Nafussi et al., 2001), C. gloeosporioides on papaya fruits (Li et al., 2013) and C. gloeosporioides on mango fruits (Le et al., 2010;Mansour et al., 2006;Dessalegn et al., 2013). Hot water treatment at 55 C for 3e5 min decreased the severity of anthracnose disease in mango cv. ...
... Consistent decay control (60-100% efficacy) was reported in peaches and nectarines against brown rot by treatment at 60 C for 20-60 s (Casals et al., 2010c;Karabulut et al., 2010;Spadoni et al., 2013Spadoni et al., , 2014 and in apples against bull's eye rot and blue mold by treatment at 45 C for 10 min (Neri et al., 2009;Spadoni et al., 2015a), without detrimental effects on fruit appearance and quality traits. An increase of the efficacy of treatment was achieved in some commodities by combining HWT with other non-conventional control means, such as organic salts, ethanol, biocontrol agents, and ultraviolet light (Margosan et al., 1997;Porat et al., 2000;Palou et al., 2001;Zhang et al., 2008). Moreover, it is well documented that, compared to cold treatment, several postharvest fungicides applied as heated solutions increase their deposition on/within fruit, providing a higher active ingredient residue level (Schirra et al., 2011). ...
... Thus using a method or a chemical material to delay or prevent decay in fruit is inevitable. The heat treatment of fruits and vegetables is an effective method that has been developed during the recent years and used to control rot in broccoli, orange, lemon, litchi, tubers, sweet pepper, pear and apple (Porat et al., 2000;Nafussi et al., 2001;Chen et al., 2004;Dong et al., 2004;Garcia-Jimenez et al., 2004;Olesen et al., 2004;Jemric et al., 2006;Neven et al., 2006;Zhang et al., 2008). In addition, it increases resistance to chilling injury and external damage and inhibits ripening (Woolf and Lay-Yee, 1997;Lurie, 1998;Paull and Chen, 2000). ...
Article
The objective of this research was improvement of apple hot water treatment efficiency by using acetic acid. The apples (cultivar Red Delicious) were treated using hot acetic acid solutions (1, 2 and 3%) at 50°C for 1, 2 and 3min. The results of in vitro study showed that treatment with acetic acid at 50°C can significantly reduce the growth of Penicillium expansum spores. The treatment of apples with 50°C acetic acid solutions, in particular 2% acetic acid solution for 3min or 3% acetic acid solution for 2min, had significant impacts in reducing the extent of decay of the fruit during the short time storage experiment, while this effect was not significant in the long-time storage.
... Rhodotorula glutinis combined with hot water (46 °C) for 10-20 min was able to significantly reduce blue mold decay of pear fruit by 86.7% for combined treatment and 33.3% for control after 15 days of storage at 20 °C. The same treatments led to a reduction by 93.3% for combined treatment and 53.3% for control after 60 days at 4 C followed by 15 days at 20 °C [69]. ...
... Hot water treatments are used as alternative methods to control postharvest diseases (Malakou and Nanos, 2005). In a study on controlling postharvest blue mold decay of pears with hot water, it was observed that spore germination of P. expansum was inhibited by hot (46°C) water (Zhang et al., 2008). Sour rot was reduced from 94.5% among control lemons to 49.1 and 47.2%, respectively, by immersion in potassium sorbate or sodium bicarbonate at 1% at 25°C, and to 37.0 and 15.7%, respectively, when these solutions were at 50°C (Smilanick et al., 2007). ...
Article
Full-text available
Geotrichum citri-auranti, sour rot of citrus, causes economical crop losses on Satsuma mandarin and lemon in Turkey. Because the usage of guazatine was restricted in packinghouses, new solutions are required to minimize these pathogens. Thirty-two isolates of G. citri-auranti were collected from packinghouses in Ege and the Mediterranean Region and tested against fungicides. In this project, we examined the old postharvest fungicides; guazatine, thiabendazole (TBZ) and imazalil against G. citri-auranti and new generation postharvest fungicides such as pyrimethanil, fludioxonil and azoxystrobin at different doses in vitro and in vivo. We also studied sensitivity of pathogen isolates against fungicides in vitro. All of the isolates were found resistant to imazalil and TBZ even high doses of fungicides. It was found that 28% of isolates were sensitive to guazatine and 72% resistant. Both in vitro and in vivo tested azoxystrobin did not affect pathogen growth and decay development. Only guazatine was effective on pathogens growth and decay development. In vivo tests conducted on Satsuma mandarin showed that a combination of sodium bicarbonate (2%) and guazatine (900 μg/ml) and their combination were the most effective treatments for disease development.
... The control of postharvest decay with a heat treatment (HT) involves effects on both plant pathogen and plant host (Schirra et al., 2000;Pavoncello et al., 2001). While it is known that HT can have a direct inhibitory effect on postharvest pathogens (Jemric et al., 2011;Zhang et al., 2008), the mode of action is not well understood. Fungi exposed to abiotic stress, including high temperature, will accumulate reactive oxygen species (ROS) intracellularly in a species-specific and dose-specific manner (Abrashev et al., 2008;Liu et al., 2011). ...
Article
Heat treatment (wet and dry) of fruit has been demonstrated as an effective approach for managing postharvest decay. Both direct antimicrobial effects on pathogen propagules as well as induction of host defense mechanisms have been suggested to play a role in the observed reduction of decay. In the present study, the effect of heat treatment (HT, hot water treatment at 40°C for 5 and 10min) on Monilinia fructicola and/or peach brown rot was investigated. HT inhibited spore germination and germ tube elongation of M. fructicola in vitro. HT also triggered the accumulation of reactive oxygen species (ROS), collapse of mitochondrial membrane potential and a decrease in intracellular ATP in M. fructicola. Results of the studies on peach fruit showed that HT induced the expression of defense-related genes including chitinase (CHI), β-1,3-glucanase (GNS) and phenylalanine ammonia lyase (PAL), as well as increased the activity of these enzymes in peach fruit. The HT used in this study did not appear to impair fruit quality. Our results indicate that both the direct inhibition of M. fructicola and the elicitation of defense responses in fruit by HT contribute to the observed reduction of decay in peach fruit.
... Fruit and vegetables are highly perishable products, especially during the postharvest phase and major losses are caused by postharvest pathogens (Chan and Tian, 2005;Zhang et al., 2008). Monilinia laxa, Botrytis cinerea and Penicillium expansum are among the most important postharvest pathogens on fruit and vegetables (Snowdon, 1990). ...
Article
The efficacy of Aureobasidium pullulans PL5 against different postharvest pathogens of fruits (Monilinia laxa on plums and peaches, Botrytis cinerea and Penicillium expansum on apples) were evaluated under storage conditions when applied at 108cellsml−1 and their interactions were studied in vitro and in vivo to discover the possible modes of action. Under 1.2°C and 95% relative humidity (RH) for 28days, the efficacy of PL5 against M. laxa on plums was 45%, reducing disease incidence from 78% to 43%. Under 1°C and 95% RH for 21days, the efficacy against M. laxa on peaches was 63%, reducing disease incidence from 79% to 29%. Under 4°C and 95% RH for 45days, the efficacy against B. cinerea and P. expansum on apples was 56% and 46%, respectively. In Lilly–Barnett minimal salt medium with the fungal cell walls of pathogens as sole carbon source, PL5 produced β-1,3-glucanase, exo-chitinase and endo-chitinase. Nutrient concentrations had significant effect on pathogen growth reduction by PL5. No attachment was observed in antagonist–pathogen interactions in vitro or in vivo. PL5 completely inhibited pathogen spore germination in PDB at 108cellsml−1, whereas at 106cellsml−1 the efficacy was significantly decreased. However, inactivated cells and culture filtrate of PL5 had no effect on pathogen spore germination and germ tube elongation. Our results showed that A. pullulans PL5 could be introduced in commercial formulations to control postharvest pathogens on fruits and its activity was based on secretion of lytic enzymes and competition for nutrients.
... Consistent decay control (60-100% efficacy) was reported in peaches and nectarines against brown rot by treatment at 60 C for 20-60 s (Casals et al., 2010c;Karabulut et al., 2010;Spadoni et al., 2013Spadoni et al., , 2014 and in apples against bull's eye rot and blue mold by treatment at 45 C for 10 min (Neri et al., 2009;Spadoni et al., 2015a), without detrimental effects on fruit appearance and quality traits. An increase of the efficacy of treatment was achieved in some commodities by combining HWT with other non-conventional control means, such as organic salts, ethanol, biocontrol agents, and ultraviolet light (Margosan et al., 1997;Porat et al., 2000;Palou et al., 2001;Zhang et al., 2008). Moreover, it is well documented that, compared to cold treatment, several postharvest fungicides applied as heated solutions increase their deposition on/within fruit, providing a higher active ingredient residue level (Schirra et al., 2011). ...
Article
Physical treatments have gained great interest in recent years to control many postharvest diseases in fruits and vegetables because the total absence of residues in the treated product and minimal environmental impact. The present review shows the extensive research work conducted during many years and increased in the last 10 years, developing physical means for consistent disease control. The review include the use of cold storage as the main physical method for delaying or reducing biotic and abiotic diseases. Physical treatments, like heat, including hot water and hot air treatments, radio frequency and microwave, hypobaric and hyperbaric pressure and far ultraviolet radiation (UV-C light), are treated as promising control means, and controlled and modified atmospheres as complementary physical tools essential to reduce or delay the development of postharvest pathogens. A particular emphasis is given to the mode of action, which involve direct effect to the pathogen (lethal or sub-lethal) of spore germination and mycelial growth of fungi and the resistance induction in the host which is not well known but nowadays, with the new tools available in molecular biology will be easy to highlight other physiological and biochemical pathways on which the phenomenon are based. Besides benefits of treatment in different commodities, also limitations of use, including low persistence, risk of adverse effects and technological problems for commercial application are discussed.
... Heat treatment (HT) is one of the most commonly used physical measures to reduce fruit decay, which has been reported to be effective in decreasing fly infestation, inducing resistance to chilling injury and enhancing the 2 Journal of Food Quality biocontrol effectiveness of antagonistic yeasts [10][11][12]. Previous reports also showed that heat treatment enhanced the efficacy of preservative and decreased the amount of chemicals used for decay control in fruits [13,14]. ...
Article
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Heat treatment and preservative application have been widely used during postharvest storage of many fresh products, but the effect of their combination on citrus storage has rarely been investigated. In this study, the optimal heat treatment (HT) conditions and HT combined with preservative treatment were investigated for Ponkan fruit ( Citrus reticulata Blanco cv. Ponkan) storage. Results indicated that HT at 55°C for 20 s can significantly reduce the decay rate of Ponkan fruit, and a combination of HT and 25% of the preservative dosage used in production of iminoctadine tris (albesilate), 2,4-dichlorophenoxyacetic acid, and imazalil significantly reduced the decay rate without affecting fruit quality. In addition, the increased fiber contents in fruit receiving the HT combined with preservative treatments may be a response preventing fungus infection and enhancing fruit storability and resistance. The above results suggested that the combination of HT and 25% of the preservative production dosage was optimal for controlling Ponkan fruit decay during storage.
... It has been reported that the combined treatment of hot water rinsing and brushing (HWRB) with C. laurentii inhibited sweet cherries decay caused by P. expansum and B. cinerea by 94% (Jing, Tu, Shao, & Su, 2008). R. glutinis combined with hot water (46 C) for 10e20 min was able to significantly reduce blue mold decay of pear fruit by 86.7% in for combined treatment and 33.3% for control after 15 days of storage at 20 C. The same treatments led to a reduction by 93.3% for combined treatment and 53.3% for control after 60 days at 4 C followed by 15 days at 20 C (Zhang, Wang, Huang, Dong, & Zheng, 2008). C. laurentii combined with short hot water dips (30 s at 55 C) was effective in controlling Rhizopus rot of strawberries (Zhang, Zheng, Wang, Li, & Liu, 2007), while heat treatment in combination with C. laurentii controlled decays caused by P. expansum and Rhizopus stolonifer in peach fruits ( . ...
Article
Background The application of physical (thermal and non-thermal) treatments in combination with biocontrol agents for the control of postharvest fungi has achieved significant research attention. In order to make combined nonchemical agents commercially suitable for postharvest treatment of other commodities, there is the need to study their individual effects and then integrated effects to present them as economically viable, resilient and persistent. Scope and approach In this article, various physical treatment methods (thermal and non-thermal) have been used to enhance the bioefficacy of microbial agents against postharvest diseases of fruits and the possible mode of action were reviewed. Additionally, the interrelationship between fungal virulence, host response and environmental factors that influence infection rate and production of mycotoxin has also been highlighted. Key findings and conclusions Physical treatments act as disinfectants of surfaces of produce prior to application of antagonistic yeasts that provide persistent protective action over an extensive period. Physical methods by heat treatment tends to seal or cure openings on the produce in order to limit the sites for pathogen penetration and restriction of secondary infections by biofilm formation after application of antagonistic yeasts or bioactive compounds. Thus, this phenomenon slow down changes in fruits respiration and metabolic activity. Heat has the potential to up-regulate proteins in fruits, which correlates with defense response and redox metabolism; consequently, demonstrates a physiological adaptation to environmental stress. From literature, there is limited information on the effect of ohmic heat method combined with antagonistic on decay causing pathogens and shelf life of fruits. Furthermore, the employment of novel tools available in molecular biology will enable in-depth explanation of other physiological and biochemical pathways on which the treatment effects are supported.
... Hot water treatment (HWT) has been widely investigated as an effective method for the control of postharvest decay of fruit (Lurie, 1998). Several studies have shown that HWT has been successfully used to control postharvest diseases in many fruits such as pears, lemon, papaya, peach, nectarine, plum and mango (Nafussi et al., 2001;Zhang et al., 2008;Karabulut et al., 2010;Le et al., 2010;Li et al., 2013). With dragon fruit, HWT has been used for controlling postharvest diseases and for maintaining the quality of the fruit. ...
Article
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The effects of food additives (sodium carbonate, SC and potassium sorbate, PS) at 0%, 1%, 2%, 3% and 4% weight per volume on fungal spore germination of dragon fruit rot diseases, Colletotrichum gloeosporioides, C. capsici and Fusarium sp. were investigated on media. PS at all concentrations showed complete inhibition of spore germination in the three fungi. SC 2% inhibited the germination of C. gloeosporioides by 100% while SC 3% completely inhibited the germination of C. capsici and Fusarium sp. PS solution was selected to study its combined effects with hot water treatment on fruit rot disease and quality of dragon fruit artificially inoculated with C. gloeosporioides. The fruit samples were treated in a heated (55 °C) solution of 1% PS for 5 min and then cooled in tap water at 10 °C (PS-55 °C + cold H2O). Non-treated fruit and fruit treated with the fungicide carbendazim were used as controls. All samples were assessed after being kept at 13 °C for 15 d. The treatment of PS-55 °C + cold H2O reduced the severity of diseases and helped to delay chlorophyll degradation in the dragon fruit bracts, had little impact on the respiration rate, delayed ethylene production and maintained the total ascorbic acid content. However, PS-55 °C + cold H2O treatment, while having little initial effect, did reduce fruit firmness after 15 d of storage. The PS-55 °C + cold H2O treatment did not affect weight loss or the total soluble solids concentration. These findings showed that the PS-55 °C + cold H2O treatment could act as a safe alternative method for suppressing fruit rot disease while maintaining the quality of dragon fruit during cold storage.
... An antagonistic Rhodotorula strain has been reported as an effective biocontrol agent against postharvest decay of apples, pears, sweet cherries, and oranges. Rhodotorula glutinis is an effective biocontrol agent against postharvest fungal spoilage of apples [16] pears [17] oranges [18] sweet cherries [19] as well as strawberries [20]. ...
... Our experiment showed that the fungistatic effect was stable for at least 5 weeks as we evaluated fruit decay after 3 weeks for P. expansum and after 5 weeks for N. malicorticis. Efficacy of combined methods of HWT and biological control has already been proven successful for apple (Conway et al., 2004;Spadaro et al., 2004), citrus fruits (Porat et al., 2002;Obagwu and Korsten, 2003), pear (Zhang et al., 2008), ...
Article
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Postharvest food decay is one major issue for today's food loss along the supply chain. Hot water treatment (HWT), a sustainable method to reduce pathogen-induced postharvest fruit decay, has been proven to be effective on a variety of crops. However, the microbiome response to HWT is still unknown, and the role of postharvest microbiota for fruit quality is largely unexplored. To study both, we applied a combined approach of metabarcoding analysis and real time qPCR for microbiome tracking. Overall, HWT was highly effective in reducing rot symptoms on apples under commercial conditions, and induced only slight changes to the fungal microbiota, and insignificantly affected the bacterial community. Pathogen infection, however, significantly decreased the bacterial and fungal diversity, and especially rare taxa were almost eradicated in diseased apples. Here, about 90% of the total fungal community was composed by co-occurring storage pathogens Neofabraea alba and Penicillium expansum. Additionally, the prokaryote to eukaryote ratio, almost balanced in apples before storage, was shifted to 0.6% bacteria and 99.4% fungi in diseased apples, albeit the total bacterial abundance was stable across all samples. Healthy stored apples shared 18 bacterial and 4 fungal taxa that were not found in diseased apples; therefore, defining a health-related postharvest microbiome. In addition, applying a combined approach of HWT and a biological control consortium consisting of Pantoea vagans 14E4, Bacillus amyloliquefaciens 14C9 and Pseudomonas paralactis 6F3, were proven to be efficient in reducing both postharvest pathogens. Our results provide first insights into the microbiome response to HWT, and suggest a combined treatment with biological control agents.
... The application of strain BIO126 of M. pulcherrima after treatment with hot water at 50°C for 3 min improved the biocontrol efficacy of M. pulcherrima against P. expansum and Botrytis cinerea in apple (Spadaro et al., 2004). Zhang et al. (2007Zhang et al. ( , 2008 demonstrated that a heat treatment at 37°C for 48 h combined with the biocontrol agents C. laurentii or Rhodotorula glutinis controlled postharvest decay in peaches and pears caused by P. expansum and Rhizopus stolonifer (Ehrenb.) Vuill., respectively. ...
... 5% de probabilidade. °C / 6 min retardou, mas não inibiu completamente o crescimento micelial de C. musae, porém foi efetivo no controle da podridão nos frutos de bananeira. Trabalho recente demonstrou que a germinação de esporos de P. expansum, causador do bolor azul em peras, foi inibida através do tratamento hidrotérmico a 46 °C por 15 ou 20 min(ZHANG et. al., 2008).MARQUENIE et al. (2002) constataram completa inativação de esporos de B. cinerea e Monilinia fructigena pelo tratamento a 45 °C / 15 min e 45 °C / 3 min, respectivamente.4.4 Efeito do dióxido de carbono (CO 2 ) no controle in vivo da antracnose em goiabasO dióxido de carbono, nas concentrações de 50, 60 e 70 %, aplicado nos frutos por 2 ...
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Postharvest decay and insect infestation are two major causes that contribute towards higher postharvest losses during the fresh produce supply chain. Although decay and pest infestation could be controlled successfully via pesticide applications, the use of chemicals at the postharvest stage is becoming limited due to the strict regulations regarding pesticide residue levels enforced by importing countries. Heat treatments are environmentally friendly and recommended as alternative treatments to replace pesticide applications, especially with regard to fresh produce. These treatments help to eradicate pathogens or pests that are present on the fruit surface while maintaining the overall quality of the fresh produce during the supply chain. Browning is regarded as an economically important physiological disorder that causes detrimental effects on the quality maintenance of fresh-cut produce. Contamination of fresh produce by foodborne pathogens could occur at any stage during the production, harvesting, postharvest chain, or processing, and heat treatments could be recommended as an antibrowning or disinfection treatment for the fresh-cut industry. In light of the above, this review summarizes the effects of postharvest heat treatments on postharvest decay, insect infestation, physiological disorders, fruit ripening, retention of color, and bioactive compounds.
Conference Paper
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Istraživano je djelovanje tretmana toplim zrakom (zagrijavanje plodova toplim zrakom do 45° C kraj koštice – HAT) i potapanja u toplu vodu na temperaturi od 48° C u trajanju od 6 minuta (HWD 48) i 52° C u trajanju od 2 minute (HWD 52) na udio trulih plodova nektarine (Prunus persica var. nectarina cv. Fantasia) nakon dva i četiri tjedna čuvanja na 0° C. Nakon tri dana držanja na sobnoj temperaturi, određen je udio plodova sa simptomima gljivičnih bolesti (Monilia laxa, M. fructigena i Rhizopus stolonifer). Najzastupljeniji patogen bila je M. laxa (42, 35 % od ukupnog broja plodova), zatim M. fructigena (3, 82 %) i R. stolonifer (3, 30 %).U tretmanu HWD 48 bilo je najmanje trulih plodova nakon dva tjedna čuvanja, dok je nakon četiri tjedna čuvanja najmanje trulih plodova bilo u tretmanu HWD 52. Nije bilo statistički značajne razlike između ovih dvaju tretmana u oba vremena čuvanja koji su značajno smanjili trulež plodova u usporedbi s kontrolom i HAT. Potrebno je optimizirati njihovu učinkovitost i istražiti djelovanje na kakvoću plodova.
Chapter
Introduction Hot Water Technologies Combination Treatments Hot Water Treatments and Fresh Cut Summary and Conclusions Acknowledgment Literature Cited
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A method was developed and optimized for the accelerated ripening of date fruits of cultivar ‘Mazafati’ to prevent diseases and decay. The date fruits were incubated in hot acetic acid solution 0.5% at 40+1°C for 72h. During the process some physicochemical changes in the fruits were studied and were found to be comparable with the changes in the fruits that naturally ripened on the tree. Fruit firmness, water insoluble solid (WIS), protein, pH, L*a*b* and E decreased during accelerated ripening whereas in control samples at 4°C increased. Total solid (TS), total soluble solid (TSS) and acidity were slightly higher in treated fruits compared to control fruits. The greatest loss of fruit firmness occurred during the first 12h of incubation. Organoleptic tests also showed little difference between the naturally ripened fruits on trees and accelerated ripened fruits in hot acetic acid. Overall there was no difference between the fruits and were readily acceptable to consumers.
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An antagonistic isolate Bacillus amyloliquefaciens HF-01, sodium bicarbonate (SBC) and hot water treatment (HW) were investigated individually and in combination against green and blue mold and sour rot caused by Penicillium digitatum, P. italicum and Geotrichum citri-aurantii respectively, in mandarin fruit. Populations of antagonists were stable in the presence of 1% or 2% SBC treatment, and spore germination of pathogens in potato dextrose broth was greatly controlled by the hot water treatment of 45 °C for 2 min. Individual application of sodium bicarbonate at low rates and hot water treatment, although reducing disease incidence after 8 weeks or 4 weeks of storage at 6 °C or 25 °C respectively, was not as effective as the fungicide treatment. The treatment comprising B. amyloliquefaciens combined with 2% SBC or/and HW (45 °C for 2 min) was as effective as the fungicide treatment and reduced decay to less than 80% compared to the control. B. amyloliquefaciens HF-01 alone or in combination with 2% SBC or/and HW significantly reduced postharvest decay without impairing fruit quality after storage at 25 °C for 4 weeks or at 6 °C for 8 weeks. These results suggest that the combination of B. amyloliquefaciens HF-01, SBC and HW could be a promising method for the control of postharvest decay on citrus while maintaining fruit quality after harvest.
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Chapter
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The past twenty years has seen the field of postharvest biocontrol evolve into a sophisticated science with global research programs worldwide, numerous yearly publications, patented technologies, and the development of new commercial products. The use of these products, however, still remains limited. The practical application of postharvest biocontrol has changed from a very classical view of using one organism to control another organism to a broader, more integrated approach where antagonists are combined with natural products, physical treatments, and used with both a pre-and postharvest application. These integrated approaches offer the potential of helping to overcome problems related to the performance of postharvest biocontrol agents and are generally used to increase reliability and efficacy. These integrated approaches, however, need to be standardized if they are to be readily adopted by industry. Continued research is needed on many aspects of the science and technology of postharvest biocontrol in order to integrate biocontrol agents into a combined pre-and postharvest production and handling system. The tools of molecular biology, such as genome sequences, microarrays, and genetic transformation now provide the ability to develop a better understanding of the mode of action of postharvest biocontrol agents as part of a tritrophic interaction between the host, antagonist, and pathogen. From an industrial viewpoint, knowledge regarding the short and long term effects of fermentation and packaging technologies on efficacy is still very rudimentary. These topics are reviewed with the objective of highlighting the barriers that need to be overcome for the widespread commercialization of postharvest bicontrol agents.
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Chapter
The postharvest phase has been considered a very suitable environment for successful application of biological control agents (BCAs) due to several parameters, such as temperature, oxygen composition and humidity that can be easily controlled. In addition, the knowledge of the main modes of action of BCAs is essential in order to enhance their viability and increase their potentiality in disease control to determining their successful activity. The antagonists display a wide range of modes of action: antibiosis, competition for nutrients and space, parasitism and induction of resistance, considered the main ones. Their efficacy, however, is related to the host and the pathogen; sometimes, different modes act simultaneously, and it is therefore difficult to establish which individual mechanism has contributed to a specific antifungal action.
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Due perishable nature of peach, it does not maintain its quality after harvest for an extended period. In order to increase or enhance the shelf life of peach to meet consumer's demand, a number of techniques such as treatment of fruit with hot water play key role in influencing fruit ripening processes. To study hot water treatment effect fruit quality and storability of peach fruit cv. 'Early Grand', an experiment was conducted at Post-harvest laboratory, Department of Horticulture, The University of Agriculture Peshawar using experimental design Completely Randomized Design (CRD) with two factors having and three replications. Healthy and disease free peach fruits were dipped in hot water at various temperatures (30, 40 and 50 o C) for five minutes and stored for various storage durations (0, 10, 20 and 30 days). The results revealed that hot water treatment (10 to 50 o C) significantly increased total soluble solid, TSS/TA ratio, total sugar, and decreased titratable acidity and ascorbic acid content of peach fruit. While increasing hot water treatment up to 40 0 C, significantly increased fruit firmness and decreased weight loss and percent disease incidence of fruit. Similarly, total soluble solid, total sugar (%), TSS/TA ratio, weight loss increased, while fruit firmness, titratable acidity and ascorbic acid decreased in freshly harvested peach fruit to fruit stored for 30 days. It could be concluded that the hot water treatments at 40 o C and storage period for 10 days induce best results on postharvest life of peach.
Article
The potential of using hot water (2.5 min at 45°C), 2% sodium carbonate or 2% sodium bicarbonate solutions alone or combined with hot water, for control of Penicillium digitatum (green mould) was investigated on commecially ripe clementines. The effect of such treatments on the post-harvest storage life of clementines was determined during two months analysing weight loss, increase in rind deformation and internal maturity. Carbonate and bicarbonate solutions effectively control green mould during storage but hot water does not. Compared with the control and hot-water treated fruits, clementines treated with carbonate and, to a lesser extend with bicarbonate, showed higher weight loss and lower firmness during storage. In contrast, lower increase in ripening index was found when the fruits were treated with carbonate or bicarbonate. Fruits treated with hot water alone or combined with carbonate exhibited no change in ripening during the first month of storage. Rinsing the fruit significantly reduces weight and firmness loss in the fruits treated with carbonate and bicarbonate, but did not change the ripening index. The primary finding of this work was that carbonate and bicarbonate treatments might significantly increase the loss in weight and firmness during storage. Rinsing the fruit immediately after treatment appeared to be a simple solution to avoid these losses in quality.
Article
Chemical fungicides currently provide the primary means for controlling postharvest decay in citrus fruit. However, consumer demands for pesticide-free food and the development of pathogenic strains that are resistant to currently used fungicides necessitates the development of alternative methods for decay control. In the present study, we show that the integrated application of various "safe" postharvest treatments, including hot-water rinsing and brushing (HWB), sodium bicarbonate (SBC) (baking soda) and biocontrol by yeast antagonists, can reduce decay development almost as well as imazalil. Application of HWB (62°C for 20 s), SBC (2%, W/V) or Candida oleophila yeast cells (108 cells ml-1) 24 h after artificial inoculation of grapefruit with Pencillium digitatum (Pers.: Fr.) Sacc. reduced decay development in the infected wounds by 68, 61 or 23%, respectively. The combination of any two of these treatments or all three of them together reduced decay by 87 to 89% from the level in untreated control fruit. Similarly, HWB, SBC or yeast antagonists reduced decay development following natural infection of wounded fruit by 42, 72 and 69%, respectively. The combination of any two of these treatments or all three together reduced decay by 87 to 90% from that in control fruit. HWB and SBC had sanitizing effects and could disinfect inoculated wounds, while C. oleophila and SBC gave residual protection against later infection in the treated wounds. Postharvest storage experiments with 'Shamouti' orange and 'Star Ruby' grapefruit showed that combined treatments of HWB and yeasts, HWB and SBC, and SBC and yeasts reduced decay development by an average of 80-85% as compared with a 95% reduction observed for imazalil. Thus, the combination of different fungicide-free safe postharvest treatments may be almost as effective as commercial treatment with imazalil.
Article
Applications of Pseudomonas cepacia reduced postharvest green mold (Penicillium digitatum) by more than 80% in lemon fruit (Citrus limon) compared with controls. The bacterium grew rapidly in wounds and caused no visible injury to the fruit. Decay was controlled if P. cepacia was applied within 12 hr or less after inoculation. The fungicides imazalil and thiabendazole were better eradicants; they were effective when applied 24 hr after inoculation. Other pseudomonads were not as effective as P. cepacia. Inhibition of fungal growth in vitro by P. cepacia reportedly is caused by the antibiotic pyrrolnitrin(.)
Article
The potential of using Pantoea agglomerans (strain CPA-2) alone, or in combination with sodium bicarbonate or sodium carbonate solutions, for control of Penicillium digitatum (green mold) and Penicillium italicum (blue mold) on oranges was investigated under ambient (20 °C) and cold storage (3 °C) conditions. P. agglomerans controlled both pathogens on oranges at 2 × 108 cfu ml-1. The biocontrol agent was found to be completely tolerant to 2% sodium bicarbonate at room temperature, although its culturability was reduced by > 1000-fold after 30 min in 2% sodium carbonate. The efficacy of P. agglomerans for control of green mold was improved when combined with sodium bicarbonate, resulting in complete and 97.6% reduction of decay incidence at 3 °C and 20 °C, when compared to untreated controls. Satisfactory results were also obtained with the combined treatment for control of blue mold. P. agglomerans grew well inside wounds on oranges at both 20 °C and 3 °C. In contrast, it showed a reduced growth on the surface of intact fruit. Sodium bicarbonate at 2% concentration did not noticeably affect antagonist population development. Thus, use of bicarbonate treatment at 2% followed by the antagonist P. agglomerans CPA-2 could be an alternative to chemicals for control of postharvest diseases on oranges.
Article
Populations of Botrytis spp., Penicillium spp., and Mucor piriformis were determined during two seasons in air and dump-tank water of nine apple and pear packinghouses. Populations of all fungi varied considerably among packinghouses. Spores of Penicillium spp. were more abundant in air and dump water than spores of Botrytis spp. or M. piriformis. Spores of Penicillium spp. and M. piriformis in dump water increased as the packing season progressed, suggesting that decaying fruit stored in bins and processed later in the season increased propagule levels more than did debris brought into packinghouses from orchards early in the season. Selected isolates were characterized for pathogenicity and virulence on Anjou pear fruit and resistance to benomyl. Sixty, 72, and 89% of Botrytis spp., Penicillium spp., and M. piriformis isolates, respectively, were pathogenic on pear fruit. The percentage of pathogenic Penicillium spp. isolates resistant to benomyl also increased later in the season. Benomyl-resistant isolates of Penicillium spp. were less virulent than benomyl-sensitive isolates. The percentage of Penicillium spp. isolates resistant to benomyl in the Mid-Columbia region has not increased during the last 5 yr.
Article
Rhodotorula glutinis was evaluated for its activity in reducing postharvest gray mold decay of strawberry caused by Botrytis cinerea in vitro and in vivo. In the test on PDA plates, R. glutinis significantly inhibit the growth of B. cinerea. Spore germination of pathogens in PDB was greatly controlled in the presence of living cell suspensions. Rapid colonization of the yeast in wounds was observed during the first 3 days at 20°C, and then the populations stabilized for the remaining storage period. On strawberry wounds kept at 4°C, the increase in population density of R. glutinis was lower than those kept at 20°C, but continued over 8 days after application of the antagonist until it reached a high level. Number of inoculated strawberry fruit treated with 1×108CFU/ml washed cell suspension of R. glutinis was 10% after 2 days at 20°C, compared to 100%, respectively, in the control. Washed cell suspensions of yeast controlled gray mold better than yeast in culture broth. Treatment of wounds with autoclaved cell cultures or cell-free culture filtrate did not prevent decay. The concentrations of antagonist had significant effects on biocontrol effectiveness: the higher the concentrations of the antagonist, the lower the disease incidence regardless of whether the fruit was stored at 20°C for 2 days or 4°C for 7 days. At concentrations of R. glutinis 1×109CFU/ml, the incidence of gray mold was reduced by 94.7 or 95%, respectively, compared with control, after storage at 20°C for 2 days or 4°C for 7 days, respectively. R. glutinis significantly reduced the natural development of decay of fruit following storage at 20°C for 3 days or 4°C for 5 days followed by 20°C for 3 days.
Article
The potential of using microwave power alone or in combination with an antagonistic yeast for the control of blue mold rot of pear, and its effects on postharvest quality of fruit was investigated. In vitro test, growth of Penicillium expansum was completely inhibited by a 2450MHz microwave heating for 2 or 3min. The population density of P. expansum in surface wounds of fruit treated with microwave for 2–3min was significantly lower than that of control. In vivo test, microwave power and antagonist yeast, as stand-alone treatments, were capable of reducing the percentage of infected wounds from 100% to 72.6% and 65.5%, and lesion diameter from 2.81mm to 2.20mm and 1.85mm respectively. However, in fruit treated with combination of microwave power and Cryptococcus laurentii, the percentage of infected wounds and lesion diameter was only 20.2% and 1.1mm respectively, incidence of natural decay on treated fruits were similar to that of inoculated fruit. None of the treatments did impair quality parameters of fruit. Thus, the combination of microwave and C. laurentii could be an alternative to chemicals for the control of postharvest blue mold rot on pear fruits.
Article
The storage response of cactus pear [Opuntia ficus-indica Miller (L.)] following hot water brushing was investigated. Fruit were simultaneously brushed for spine removal and sprayed with water. Ranges of temperature (60–70°C) and treatment time intervals (10–30s) were evaluated. All tested treatments were found not to significantly affect respiration rate, total soluble solids or acid concentrations. Treatments at 60 and 65°C were found to reduce water loss and the incidence of rusty-brown spots on fruit peel. At higher temperatures, some negative effects were observed, namely increased electrolyte leakage and extended light brown areas on the fruit peel, indicating heat damage to the fruit. All the treatments effectively controlled decay in fruit stored at 6±1°C for 4 weeks followed by 1 week at 20±1°C. The effectiveness of treatments to control decay was increased with temperature and treatment time. Based on the results of this study, treatments at 60°C for 30s or 65°C for 20s reduced the decay incidence by 86–91% without compromising fruit quality. These treatments can be easily applied in commercial practice with slight modification of the despining facilities in use.
Article
Spores of Monilinia fructicola or Rhizopus stolonifer were immersed in water or 10% ethanol (EtOH) for 1, 2, 4, or 8 min at temperatures of 46 or 50°C to determine exposure times that would produce 95% lethality (LT95). EtOH reduced the LT95 by about 90%. Peaches and nectarines infected with M. fructicola were immersed in hot water alone or with EtOH to control decay. EtOH significantly increased the control of brown rot compared to water alone. Immersion of fruit in water at 46 or 50°C for 2.5 min reduced the incidence of decayed fruit from 82.8% to 59.3 and 38.8%, respectively. Immersion of fruit in 10% ethanol at 46 or 50°C for 2.5 min further reduced decay to 33.8 and 24.5%, respectively. Decay after triforine (1,000 μg ml-1) treatment was 32.8%. Two treatments, 10% EtOH at 50°C for 2.5 min and 20% EtOH at 46°C for 1.25 min, were selected for extensive evaluation. The flesh of EtOH-treated fruit was significantly firmer, approximately 4.4 N force, than that of control fruit among seven of nine cultivars evaluated. No other factor evaluated was significantly influenced by heated EtOH treatments. The EtOH content of fruit treated with 10 or 20% EtOH was approximately 520 and 100 μg g-1 1 day and 14 days after treatment, respectively.
Article
The yeasts Trichosporon pullulans, Cryptococcus laurentii and Rhodotorula glutinis were sprayed at a concentration of 1×108CFU/ml onto sweet cherry fruit in two orchards prior to harvest. Survival of these species on fruit surfaces under field conditions was investigated. Also, their biocontrol efficacy against postharvest decay of cherry fruit stored under various conditions was assessed. All three yeasts colonized the surface of sweet cherry fruit. However, only C. laurentii and R. glutinis maintained populations at high and stable levels throughout the 4-day experiment period. C. laurentii was the most effective and promising of the three antagonists. It had strong survival ability on fruit surfaces under field conditions, and adaptability to postharvest storage conditions of low temperature, low O2 and high CO2 concentrations.
Article
A hot water pressure process (HWP) was evaluated for its effect on conidia of Penicillium expansum and on development of blue mold, gray mold, and mucor rot of d’Anjou pear fruit. Spores were removed from the water system through dilution and also as a result of hot water in the system that was lethal to the spores. When the system was heated, viable spores were not detected after 2–4h of operation. Reductions in decay in the HWP system were 36, 29, and 13% for Botrytis cinerea, Mucor piriformis, and P. expansum, respectively. The response of P. expansum appeared related to the length of time fruit was in cold storage. Heat injury was observed on fruit treated with 40 and 50°C water but not on fruit at 30°C nozzle temperature. The HWP system described in this study should be considered as a component of an integrated decay control strategy.
Article
Spanish strawberries (Fragaria x ananassa cv. Tudla) after harvesting were not treated or subjected to heat treatment by submersion in water at different temperatures (25, 35, 45, and 55 degrees C) for 15 min. Afterward, the fruits were stored at I degrees C for 2 days. Subsequently, their ripening parameters of quality were monitored during a shelf life of 3 days at 18 degrees C. Fruits heated at 45 degrees C produced the lowest values for postharvest losses, weight loss, and titratable acidity, the highest values of fruit firmness and soluble solids content, and the best values for sensorial appearance. However, these fruits lost most rapidly the initial value of calyx color and calyx and fruit skin brightness. Heat treatment at 45 degrees C should be especially useful for strawberries with a foreseeable high incidence of decay during their shelf life.
Article
A Rhodotorula strain (Rhodotorula glutinis ySL 30) in combination with a siderophore was evaluated for postharvest control of a Botrytis cinerea strain resistant to iprodione on apple. The biocontrol yeast was less effective for the control of iprodione-resistant B. cinerea than the iprodione-sensitive B. cinerea. A combination of R. glutinis and rhodotorulic acid, a siderophore produced by yeasts belonging to Rhodotorula genus, was evaluated as a way to improve the control of the resistant strain. In experiments “in vitro”, rhodotorulic acid retarded the spore germination of the fungus, and in biocontrol experiments on apple wounds, the disease was more effectively controlled by the antagonistic agent in combination with the siderophore than by the antagonistic agent alone. R. glutinis reduced decay severity by 54% and R. glutinis in combination with siderophore reduced decay severity by 72%, in comparison with the non-treated control.
Article
The biocontrol activity of Rhodotorula glutinis on green mold decay of oranges caused by Penicillium digitatum was investigated in vitro and in vivo. Significant control was achieved with a washed cell suspension and an unwashed cell culture mixture of R.glutinis. Treatment of wounds with autoclaved cell cultures or cell-free culture filtrate did not prevent decay. The protection provided by the washed yeast cells was dose-dependent. The higher the concentration of R.glutinis, the better the effect of the biocontrol capacity. At concentrations of yeast of 1109colony-forming units per milliliter or higher and pathogen spore suspensions of 5104spores per milliliter, green mold was almost inhibited after 4-days incubation at 20C. The interval between the pathogen inoculation and the antagonist application significantly influenced the biocontrol ability. The biocontrol efficacy of R.glutinis applied before the pathogen was better than that of applied after the pathogen. Surprisingly, R.glutinis was also effective in controlling green mold at low temperature (4C). Rapid colonization of the yeast in wounds was observed during the first 3days at 20C, and remained stable after 5-days incubation. On fruits stored at 4C, even after 21days, the population of R.glutinis in wounded fruits was more than 1,600-fold of what it was just prior to storage. In the test on potato dextrose agar plates, agar disks of R.glutinis nutrient yeast dextrose agar cultures placed on PDA plates seeded with pathogens did not inhibit the growth of P.digitatum. Spore germination of pathogens in potato dextrose broth was greatly controlled in the presence of living cell suspensions.
Article
The effects of combinational use of controlled atmosphere (CA), Semperfresh edible coating (sucrose polyester base coating) and cold storage on shelf life, quality attributes and post storage life of green slender peppers (Capsicum annuum L.) were investigated. Changes in weight, quality, pH, total titratable acidity, ascorbic acid, soluble solids, respiration rate and total chlorophyll content were recorded periodically for comparing the effects of the applied conditions. In the study, application of CA storage was determined to give the best results in terms of the analyzed parameters. Use of Semperfresh in combination with cold storage was significantly effective in retaining higher contents of vitamin C, and total chlorophyll. However, it didn't provide a synergetic benefit for improving the quality of the peppers under CA and normal air conditions.
Article
Advanced maturity nectarines cv. Caldesi 2000 [Prunus persica var. nectarina (Ait.) Maxim.] and peaches cv. Royal Glory [Prunus persica (L.) Batch] were treated in 46 °C hot water containing 200 mM NaCl for 25 min, sealed in low thickness PE bags and stored at 0 °C for 1 and 2 weeks. Quality was evaluated initially and after each storage period plus 1 day shelf life. Hot water treatment (an acceptable treatment to reduce spoilage from fungi) did not cause any fruit damage based on external observations, specific conductivity and total phenol content evaluations, but reduced firmness loss (possibly in combination with MA packaging) especially in the white-flesh nectarines and kept the cellular membranes functioning better. PE bags were of low thickness and MA conditions inside the bags were found inadequate (O2 levels >15%, CO2 levels <5%) to significantly affect the ripening process during cold storage, but could be harmful after 10 h at room temperature (O2 levels <3%, CO2 levels >13%). Mass losses were kept low in PE bags. Juice soluble solids concentration, pH and acidity were not affected by the hot water treatment before and after cold storage. Hot water combined with MA packaging during storage resulted in good quality fruit after 1 week duration for postharvest handling.
Article
Bacillus subtilis isolates F1, L2, and L2-5, isolated from citrus fruit surfaces were evaluated for control of citrus green and blue molds caused by Penicillium digitatum and P. italicum, respectively. These isolates were evaluated alone, or in combination with sodium bicarbonate (SB) or hot (45 °C) water treatment on artificially inoculated ‘Valencia’ and ‘Shamouti’ orange cultivars. Treated fruit were stored at 10±1 °C, and 90–95% relative humidity (RH) for 4 weeks. When applied alone, all isolates performed significantly better than the water control in checking the incidence of both green and blue molds, but were not as effective as the fungicide (quazatine plus imazalil) treatment. Isolate F1 was more effective than L2 and L2-5 in this respect. A significant increase in biocontrol activity of all isolates was observed when isolates were combined with SB, or when applied following hot water treatment. The treatments comprising F1 combined with SB or F1 applied following hot water treatment was as effective as the fungicide treatment, which gave 100% control of both green and blue molds on both cultivars.
Article
The efficacy of hot water, biological control and controlled atmospheres (CA), alone and in combinations, in controlling gray mold on harvested strawberry fruit was tested. All fruit were wound inoculated with Botrytis cinerea Pers.:Fr. Inoculated fruit were subsequently dipped in hot water at 63 °C for 12 s, inoculated with a biological control yeast, Pichia guilliermondii Wickerham, and/or immediately stored at 5 °C under air or 15 kPa CO2 for 5 and 14 days followed by 2 days at 20 °C to simulate market conditions. Fruit treated with the combination of heat, biocontrol, and CA had significantly less decay than those in all of the other treatments after 5 days at 5 °C plus 2 days at 20 °C. After 14 days at 5 °C and 14 days at 5 °C plus 2 days at 20 °C, the heat+biocontrol+CA treatment continued to control decay though not significantly more than CA alone, biocontrol+CA, or heat+CA treatments. Some damage occurred following heat treatment; however, quality parameters did not differ between treatments. Overall, the combination treatments did not provide better control than the current commercially used treatment of 15 kPa CO2.
Article
‘Golden Delicious’ apples were wound inoculated with conidial suspensions of either Colletotrichum acutatum or Penicillium expansum, then treated with heat (38 °C) for 4 days, sodium bicarbonate, and/or one of two heat tolerant biocontrol agents (yeasts). Following four months storage at 0 °C, the apples were left at room temperature for two weeks. Populations of antagonists were stable throughout the experiment and were higher on the heated than the non-heated fruit. Both antagonists reduced decay caused by P. expansum, whereas heat or heat in combination with either antagonist eliminated decay. Either heat or the antagonists alone reduced decay caused by C. acutatum, but a combination of the two was required to completely eliminate decay caused by this pathogen. Adding sodium bicarbonate to the heated or antagonist-treated fruit had little effect on decay caused by either pathogen but when used on non-heated fruit, it significantly reduced decay severity caused by P. expansum after four months at 0 °C. The goal of this research is to combine alternative methods of control to provide an effective substitute for synthetic pesticides.
Article
Prestorage heat treatment appears to be a promising method of postharvest control of decay. Heat treatments against pathogens may be applied to fresh harvested commodities by hot water dips, by vapour heat, by hot dry air or by a very short hot water rinse and brushing. Heat treatments have a direct effect slowing germ tube elongation or of inactivating or outright killing germinating spores, thus reducing the effective inoculum size and minimising rots. Heat treatment can also indirectly affect decay development via physiological responses of the fruit tissue. These responses include inducing antifungal-like substances that inhibit fungal development in the fruit tissue, or enhancing wound healing. Heat treatment can induce PR proteins such as chitinase and β-1,3 glucanase, stabilise membranes, elicit antifungal compounds, or inhibit the synthesis of cell wall hydrolytic enzymes (polygalacturonases), and delay the degradation rate of pre-formed antifungal compounds that are present in unripe fruit. Additionally, curing, as a heat treatment can cause the disappearance of wax platelets normally present in untreated fruit and make the fruit surface relatively homogeneous. Thus, cuticular fractures, microwounds and most stomata are partially or completely filled, and early-germinated spores are encapsulated and inactivated by molten wax. The occlusion of possible gaps for wound pathogens as well as the encapsulation and inactivation of early-germinated spores have been considered as additional factors in fruit protection against decay.
Article
Changes in quality, retinol equivalents (RE) and individual provitamin A carotenoids in fresh cut ‘Fay Elberta’ peaches (Prunus persica (L.) Batsch) held for 7 days and ‘Fuyu’ persimmons (Diospyros kaki L.) held for 8 days at 5 °C in air or controlled atmospheres were evaluated. Controlled atmospheres of 2% O2, 12% CO2 in air, and 2% O2 + 12% CO2 had no effect on quality attributes of sliced peaches over 7 days of storage. Visual quality of persimmon slices was slightly enhanced by the treatments containing 12% CO2, which also resulted in significant differences in color. Peach slices stored in air + 12% CO2 had a lower content of β-carotene and β-cryptoxanthin, resulting in lower RE than the other treatments. The various carotenoids found in persimmon slices responded differently to the tested atmospheres; storage in 2% O2 or air + 12% CO2 tended to result in lower RE after 8 days, but the loss was not significant for fruit stored under 2% O2 + 12% CO2. For sliced peaches and persimmons, the limit of shelf life was reached before major losses of carotenoids occurred.
Article
The potential of using heat treatment alone or in combination with an antagonistic yeast for the control of blue mold decay and Rhizopus decay of peaches caused by Penicillium expansum and Rhizopus stolonifer respectively, and in reducing natural decay development of peach fruits, as well as its effects on postharvest quality of fruit was investigated. In vitro tests, spore germination of pathogens in PDB was greatly controlled by the heat treatment of 37 degrees C for 2 d. In vivo test to control blue mold decay of peaches, heat treatment and antagonist yeast, as stand-alone treatments, were capable of reducing the percentage of infected wounds from 92.5% to 52.5% and 62.5%, respectively, when peach fruits stored at 25 degrees C for 6 d. However, in fruit treated with combination of heat treatment and Cryptococcus laurentii, the percentage of infected wounds of blue mold decay was only 22.5%. The test of using heat treatment alone or in combination with C. laurentii to control Rhizopus decay of peaches gave a similar result. The application of heat treatment and C. laurentii resulted in low average natural decay incidences on peaches after storage at 4 degrees C for 30 days and 20 degrees C for 7 days ranging from 40% to 30%, compared with 20% in the control fruit. The combination of heat treatment and C. laurentii was the most effective treatment, and the percentage of decayed fruits was 20%. Heat treatment in combination with C. laurentii had no significant effect on firmness, TSS, ascorbic acid or titratable acidity compared to control fruit. Thus, the combination of heat treatment and C. laurentii could be an alternative to chemicals for the control of postharvest decay on peach fruits.
Postharvest chemicals applied to pears: a survey of pear packers in Washington
  • E A Kupferman
Kupferman, E.A., 1998. Postharvest chemicals applied to pears: a survey of pear packers in Washington, Oregon, and California. Tree Fruit Postharvest J. 9, 3–24.
Postharvest hot treatment on Spanish strawberry
  • Garcia
Postharvest chemicals applied to pears: a survey of pear packers in Washington, Oregon, and California
  • Kupferman