Yongcai Li

Gansu Agricultural University · college of Food science and Engineering

Suberin polyaliphatics (SPA) is an important component of healing closing layer at fruit wounds. However, few study is available on the effect of sodium silicon treatment on SPA monomers biosynthesis and polymerization at muskmelon wounds. In this study, sodium silicate enhanced PLA2 (Phospholipase A2, PLA2) expression and enzyme activity, increase...

UV-C could directly inactivate pathogens, and reduce postharvest diseases of fruits and vegetables by inducing resistance. To date, no studies have been carried out to verify whether UV-C may accelerate the wound healing of potato tubers. The present results demonstrated that UV-C irradiation up-regulated StPAL, St4CL, and StCAD expression and acti...

Calcium/calmodulin-dependent protein kinase (CaMK), a key downstream target protein in the Ca2+ signaling pathway of eukaryotes, plays an important regulatory role in the growth, development and pathogenicity of plant fungi. Three AaCaMKs (AaCaMK1, AaCaMK2 and AaCaMK3) with conserved PKC_like superfamily domains, ATP binding sites and ACT sites hav...

Melatonin (MT), a phytohormone, can enhance plant resistance against biotic and abiotic stresses. However, no studies have been conducted on whether MT influences suberin polyphenolic (SPP) and lignin deposition by mediating nitric oxide (NO) and reactive oxygen species (ROS). Herein, wounded tubers were treated with 50 μmol/L MT, and 25 μmol/L N ω...

Antioxidant activity is an important feature for evaluating fruit quality and tolerance to biotic or abiotic stresses. Moreover, antioxidant activity is involved in chilling injury (CI) response and postharvest quality in fruit. Chemical elicitors can induce systemic acquired resistance in fruit against pathogens, which could partially replace synt...

Ca²⁺/calcineurin signaling pathway is crucial in regulating growth, stress response and pathogenicity of phytopathogenic fungi. However, there is little information about the downstream calcineurin-responsive zinc finger transcription factor Crz1 in Alternaria alternata, the pathogenic factors of pear black spot. Here, AaCrz1 was identified in A. a...

Penicillium expansum is a necrotrophic pathogen, which actively kills host cells and obtains nutrients from dead cells to achieve infection. However, few reports have elucidated the differential levels of carbon and nitrogen sources over increasing distances of the leading edge in fungal colonized fruit tissues during colonization. Our results show...

Ca2+, as a second messenger in cells, enables organisms to adapt to different environmental stresses by rapidly sensing and responding to external stimuli. In recent years, the Ca2+ mediated calcium signaling pathway has been studied systematically in various mammals and fungi, indicating that the pathway is conserved among organisms. The pathway c...

Pear fruit is susceptible to softening and pulp disintegration leading to a short postharvest storage life. One possible method to alleviate softening is the use of edible coatings. Starch-based coatings and films were blended with cumin essential oil to investigate the film characteristics and the effect of the coating treatments on enzyme activit...

Chitooligosaccharide (COS) is a degradation product of chitosan. Although COS increased fruit resistance by regulating the metabolism of reactive oxygen species (ROS), few reports are available on whether COS regulates ROS homeostasis at wounds of potato tubers during healing. In this study, COS increased gene expression and activities of NADPH oxi...

CmrA, as transcription factor for regulating DHN-melanin synthesis, controls melanin synthesis gene expression of pksA, brm1 and brm2, and also regulate growth, development, stress response and virulence of plant fungi. However, little is known about the roles of CmrA on infection structure formation, penetration and pathogenicity of Alternaria alt...

Aims: Calmodulin (CaM), acts as a kind of multifunctional Ca2+ sensing protein, which is ubiquitous in fungi, is highly conserved across eukaryotes and is involved in the regulation of a range of physiological processes, including morphogenesis, reproduction and secondary metabolites biosynthesis. Our aim was to understand the characteristics and...

Fungal colonization causes enormous economic loss of postharvest fruit. Fungal infections increase fruit deterioration and release of volatile organic compounds (VOCs) by rotting fruit. VOCs are also released during interactions between fruit and pathogenic fungi. Mouldy odour is typical of decayed fruit. This type of odour is emitted by fruit in l...

Fungal pathogens use plant surface physiochemical signals to trigger specific developmental processes. To assess the role of Phospholipase C (PLC) in mediating plant stimuli sensing of Alternaria alternata, function of three PLC genes were characterized by constructing ΔAaPLC mutants. Here we showed that the fruit wax-coated surfaces significantly...

Sorbitol is the primary product of photosynthesis and sugar metabolism in plants. However, the mechanism by which sorbitol treatment affects potato tuber wound healing remains unclear. This study showed that sorbitol treatment reduced weight loss and disease index (inoculated with Fusarium sulphureum) of tubers during healing. Sorbitol also facilit...

Wound healing could effectively reduce the decay rate of potato tubers after harvest, but it took a long time to form typical and complete healing structures. Brassinosteroid (BR), as a sterol hormone, is important for enhancing plant resistance to abiotic and biotic stresses. However, it has not been reported that if BR affects wound healing of po...

To establish successful infections in host plants, pathogenic fungi must sense and respond to an array of stresses, such as oxidative stress. In this study, we systematically analyzed the effects of 30 mM H2O2 treatment on reactive oxygen species (ROS) metabolism in Alternaria alternata. Results showed that 30 mM H2O2 treatment lead to increased O2...

The high-osmolarity glycerol response kinase, Hog1, affects several cellular responses, but the precise regulatory role of the Hog1 mitogen-activated protein (MAP) kinase in the differentiation of the infective structure of Alternariaalternata induced by pear cuticular wax and hydrophobicity has not yet clarified. In this study, the AaHog1 in A. al...

pH is one of the important environmental factors that affect the growth, development and pathogenicity of postharvest pathogen. The transcription factor PacC dominates the pH signal pathway. PacC in Trichothecium roseum showed three typical conserved zinc finger domains and closest homology to Fusarium graminearum. T. roseum increased the environme...

Postharvest storability of Asia pears is a powerful challenge due to fungi infection. Spoilage diseases such as blue mold, black spot rot, and brown rot reduce the fruit quality and shelf-life, resulting in significant economic losses. Control of postharvest diseases with chemical fumigation has proven effective against fungal infections, however,...

Reactive oxygen species (ROS) production is essential for both physiological processes and environmental stress in diverse plants. Previous studies have found that benzo-(1, 2, 3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH)-inducible ROS were associated with wound healing of potato tubers. Calcium-dependent protein kinases (CDPKs), the impo...

Benzo-(1, 2, 3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH) is the first synthetic chemical elicitor that induces resistance against postharvest diseases in fruit and vegetables. However, little information is available on how BTH application affects membrane lipid metabolism and volatile compounds (VOCs) biosynthesis in infected fruit. The...

The high-osmolarity glycerol response (HOG) pathway is pivotal in environmental stress response, differentiation and virulence of Alternaria alternata. The synthetic high osmolarity sensitive sensor Sho1 has been postulated to regulate the HOG pathway. To determine the regulatory role of transmembrane protein Sho1 on vegetative growth, secondary me...

L-lysine, an important basic amino acid, its catabolic pathway is activated upon microbial pathogen attack in plants and has a central role in plant immunity. The control effects of exogenous L-lysine treatment on Alternaria rot in postharvest ‘Zaosu’ pear fruit and possible mechanisms involved were studied. The results showed that L-lysine treatme...

β-Aminobutyric acid (BABA) is a nonprotein amino acid that induces plant defense responses to numerous biotic and abiotic stresses. However, whether BABA treatment affects the wound healing process of potato tubers has yet to be reported. In this study, we examined the effects of BABA treatment on the weight loss and disease index of Solanum tubero...

In this study, an edible formulation consisting of modified sweet potato starch (MSPS) and cumin essential oil (CEO) was developed. The effectiveness of the coating on the physiochemical and sensory traits of ‘early crisp’ stored at 25 °C for 28 d was evaluated. The results showed that incorporation of 0.2–0.4% (v/v) CEO in modified sweet potato st...

Alternaria alternata, the casual agent of black rot of pear fruit, can sense and respond to the physicochemical cues from the host surface and form infection structures during infection. To evaluate the role of cyclic AMP-dependent protein kinase (cAMP-PKA) signaling in surface sensing of A. alternata, we isolated and functionally characterized the...

Trans-2-hexenal is a naturally occurring volatile phytochemical with antimicrobial activity. It has not been widely used for the preservation of fruit and vegetables owing to its rapid volatilization. In this study, β-cyclodextrin-trans-2-hexenal microcapsules (β-CTHM) were prepared using the saturated aqueous solution method and their efficacy in...

A novel colorimetric aptasensor based on unmodified gold nanoparticle (AuNPs) and single-strand DNA (ssDNA) aptamer was developed for the rapid and sensitive detection of T-2 toxin. In the absence of T-2, the AuNPs were wrapped by the aptamer to avoid the salt-induced aggregation and the solution remains red. In the presence of T-2, the aptamer was...

Amino acids (AAs) play a critical role in resistance response and biosynthesis of volatile compounds (VOCs) in fruit. In this study, we inoculated apple fruits (cv. Delicious) with Penicillium expansum to investigate the effect of different AA accumulation on the biosynthesis of branched-chain VOCs at different stages of colonization. Generally, in...

Benzo (1, 2, 3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH) is the first synthetic nontoxic chemical elicitor that has induced resistance in fruit and vegetables against postharvest diseases. In this study, we treated artificially wounded muskmelon fruit (Cucumis melo L. cv. Perfect) with 100 mg L⁻¹ BTH. The results indicated that there was...

Wound healing ability of potato tubers depends on cultivar. However, there are few researches on the wound healing dynamics of different potato cultivars and reports at biochemical and cellular level. In this study, the healing ability among four major potato cultivars, ‘Atlantic’, ‘Shepody’, ‘Desiree’ and ‘Favorite’ is compared after wounding the...

To investigate the mechanisms of phospholipase C (PLC)-mediated calcium (Ca2+) signaling in Alternaria alternata, the regulatory roles of PLC were elucidated using neomycin, a specific inhibitor of PLC activity. Three isotypes of PLC designated AaPLC1, AaPLC2, and AaPLC3 were identified in A. alternata through genome sequencing. qRT-PCR analysis sh...

Black spot caused by Alternaria alternata is one of the important diseases of pear fruit during storage. Isothiocyanates are known as being strong antifungal compounds in vitro against different fungi. The aim of this study was to assess the antifungal effects of the volatile compound 2-phenylethyl isothiocyanate (2-PEITC) against A. alternata in v...

The antifungal activity of benzyl isothiocyanate (BITC) against pear pathotype-Alternaria alternata, the causal agent of pear black spot, and its possible mechanisms were studied. The results indicated that both the spore germination and mycelial growth of A. alternata were significantly inhibited by BITC in a dose-dependent manner. BITC concentrat...

Muskmelons are susceptible to mechanical damage at harvest and subsequent postharvest handling before storage. The wounds provide an easy pathway for fungi to infect, leading to postharvest decay of fruit during storage. Wound healing is considered as a positive defense process, which can restrict the invasion of pathogens. In this study, muskmelon...

Benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH) can improve wound healing of potato tubers; however, how the chemical regulates reactive oxygen species (ROS) generation and scavenging during wound healing is not completely understood. BTH at 100 mg·L-1 regulated changes in ROS generation and scavenging in healing tissues of potato...

The effects of exogenous polyamines treatment on reactive oxygen species (ROS) metabolism in apricot fruits were systematically analyzed through the investigation of their curative and preventive effects on black spot disease. Results showed that 1.5 mM spermine (Spm), 1.5 mM spermidine (Spd) and 10 mM putrescine (Put) treatment significantly inhib...

Blue mold and core rot caused by Penicillium expansum and Trichothecium roseum are major diseases of apple fruit in China; however, their differential aggressiveness in apples and effect on fruit postharvest physiology are unclear. The effects of colonization of apples cv. Red Delicious by both pathogens were compared to physiological parameters of...

Mitochondria play an essential part in fighting against pathogen infection in the defense responses of fruits. In this study, we investigated the ROS production, energy metabolism and changes of mitochondrial proteins in harvested muskmelon fruits (Cucumis melo cv. Yujinxiang) inoculated with Trichothecium roseum. The results indicated that the fun...

The effects of postharvest treatment with sodium silicate (Si) (100 mM) on mitochondrial ROS production and energy metabolism of the muskmelon fruits (cv. Yujinxiang) on development of defense responses to Trichothecium roseum were studied. Si treatment decreased decay severity of inoculated muskmelons, enhanced the activities of energy metabolism...

Pink rot caused by Trichothecium roseum is a major postharvest disease of muskmelon fruit in the northwestern areas of China. The pathogen generally reduced quality of melons and enhanced loss. In this study, T. roseum infected muskmelon (Cucumis melo c v. ‘Jinhongbao’) fruits were used to investigate the effect of infection on respiration rate, et...

Fusarium rot of muskmelon, caused by Fusarium spp., is one of the most important postharvest decays, that not only causes economic losses but leads to trichothecenes contamination. A rapid and sensitive method was developed for neosolaniol (NEO) analysis in muskmelon inoculated with F. sulphureum, utilizing acetonitrile/water (84:16, v/v) extractio...

Postharvest losses due to pathogens are a major concern in agriculture and therefore new strategies to reduce these losses while making sure that the treated products are safe for the consumer, are of paramount importance. Chemical fungicides treatment is not only unsafe but also leads to pathogen developing resistance. Therefore, products that can...

The role of cuticular wax and the surface hydrophobicity of the fruit of the ‘Zaosu’ pear (Pyrus bretschneideri Rehd) in regulating the prepenetration phase of Alternaria alternata infection were analysed in vivo and in vitro. Results showed that cuticular wax on an intact fruit surface, as well as wax extracts mounted on silanized glass slides or...

Postharvest losses due to pathogens are a major concern in agriculture and therefore new strategies to reduce these losses while making sure that the treated products are safe for the consumer, are of paramount importance. Chemical fungicides treatment is not only unsafe but also leads to pathogen developing resistance. Therefore, products that can...

The induced resistance of potato tuber (Solanum tuberosum cv. Xindaping) tissue against Fusarium sulphureum by a fungal elicitor from the incompatible pathogen Trichothecium roseum and its possible mechanism were studied. The results showed that the lesion development of the wound-inoculated potato tuber was significantly reduced by treatment with...

Trichothecium roseum is one of the most important postharvest pathogens in arid and semiarid regions. Sodium silicate (NaSi) and environmental pH have significant inhibitory effects on fungal growth. However, no study has addressed the relationship of NaSi and pH in combination and the effects on T. roseum. In this work, we showed that spore germin...

Trichothecenes are one of the most important groups of mycotoxins produced by Trichothecium roseum, which causes core rot of apple. A reliable and sensitive method was developed and successfully applied to the rapid detection of trichothecenes including T-2 toxin and neosolaniol in harvested apple using UPLC-MS/MS. After the extraction of the two m...

The antifungal activity of nitric oxide (NO) on Fusarium sulphureum in vitro and curative or preventive efficacy against dry rot in potato tubers was studied. We report that NO released by sodium nitroprusside (SNP) aqueous solution strongly inhibited spore germination and mycelial growth of F. sulphureum in a concentration-dependent manner. When t...

Effects of different polarity solvents on the ultrastructure and chemical composition of cuticular wax in Pingguoli pear as well as their bioactive role against Alternaria alternate were studied and the results showed that the highest wax content was extracted with chloroform, and its wax content was up to 322.2 μg cm−2. Long-chain fatty acids pred...

Differences in virulence between Fusarium sulphureum and Fusarium sambucinum were compared. Changes in reactive oxygen species production and metabolism in inoculated slices of potato tubers were also compared. The result showed that Fusarium infection induced significant production of ROS, lipid peroxidation and loss of cell membrane integrity, bu...

To elucidate the role of fruit wax in fungal infection, changes in chemical composition of wax during fruit development of Pingguoli pear, and their role in Alternaria alternata infection were studied. Results showed that wax content increased during fruit development. Fruit harvested 130 days after full bloom (DAFB) had a peak wax content that was...

Skin browning of pear is a major postharvest physiological disease that significantly reduces the fruit appearance by showing many dark brown spots. Effects of hot water dips (HWD), individual fruit wrapping (IFW) or preharvest GA3 sprays at 50 mg/L, alone or in combination, on skin browning and storage quality of 'Pingguoli' pears stored at ambien...

Chilling injury (CI) is the primary factor limiting postharvest life during storage and transport of plum fruits at low temperatures. CI is usually manifested as dull coloration or breakdown and browning of internal tissues, loss of firmness and increased susceptibility to decay. The effect of preharvest 100 ppm GA3 sprays at three stages of fruit...

Potassium tetraborate and borax (Na2B4O7) were evaluated for their in vitro activity against Fusarium sulphureum and for their curative and preventive efficacy against postharvest dry rot infections on potato tubers. Potassium tetraborate and borax strongly inhibited spore germination (effective inhibitory dose [ED50] = 2.1 and 2.4 g/L, respectivel...

The effects of thiamine (vitamin B1) against Alternaria rot caused by Alternaria alternata and its possible mechanism in harvested Asian pear fruit were investigated. Thiamine strongly inhibited spore germination and mycelial growth of A. alternata in vitro. Thiamine at a concentration of 100 mm effectively inhibited the development of Alternaria r...

The effects of riboflavin (vitamin B2) against Alternaria rot caused by Alternaria alternata and its possible mechanism in harvested Zaosu pear fruit were investigated. Riboflavin at a concentration of 1.0 mM effectively inhibited development of Alternaria rot and enhanced the activities of defense-related enzymes, such as phenylalanine ammonia-lya...

In order to understand the cuticular wax properties of Asian pear fruits (cv. Pingguoli), a series of assays was conducted on extraction, fractionation and determination of composition. The results showed that the maximum yield of wax from the fruit was obtained by chloroform/methanol (3:1), and then by chloroform extraction. Polar and low polar fr...

Sodium silicate (Si) at 100 mM was used as a postharvest treatment agent of induction resistance on muskmelon (Cucumis melon L. cv. Yindi) to investigate the mechanism of controlling pink rot disease, which caused by Trichothecium roseum. Si treatment significantly reduced (P < 0.05) the lesion diameter of melons inoculated with T. roseum during st...

Pink rot caused by Trichotethium roseum is one of the most important postharvest pathogens of muskmelon in China. In this paper, the effect of Si on growth and histolology of T. roseum was studied in vitro. The results indicated that Si significantly inhibited mycelial growth and spores germination, increased cell membrane permeability of hyphal. T...

Dry rot, caused by Fusarium spp. is reported as the most important postharvest disease of potato in China. Fusarium sulphureum is one of the principal pathogens. Potato ('Atlantic') tuber and slices treated by sodium silicate at 100 mM were investigated to reduce dry rot and to induce defense responses. The results showed that sodium silicate signi...

Plum fruit are susceptible to chilling injury (CI) when exposed to temperatures of less than 2-5°C. The symptom is expressed as skin pitting, staining and flesh browning that increase in number and size over time. The effect of intermittent warming (IW) (10 or 15 days interval between 0°C for 9 or 14 days and 20°C for 1 day) combined with modified...

'Early Crisp' pear is one of the most important early Asia pears (Pyrus bretchneideri Rehd.) grown in the north of China. The fruit are often purchased because of its green peel, good taste and crispy flesh texture. However, postharvest yellowing of fruit happens rapidly due to limited use of refrigeration and without effective postharvest treatmen...

The effectiveness of postharvest β-aminobutyric acid (BABA) treatment was studied for inducing resistance against dry rot caused by Fusarium sulphureum in tubers and slices of two potato cultivars (resistant cultivar Shepody and susceptible cultivar Xindaping). The results showed that BABA at 100 mmol L−1 significantly reduced lesion diameter in in...

Melons fruit can be induced to develop enhanced resistance to pathogen infection by pre- or postharvest treatment with a variety of chemical, physical and biological elicitors. The elicitors include acibenzolar, soluble silicon, oxalic acid, chitosan, β-aminobutyric acid, 2,6-dichloroisonicotinic acid, heat treatment and harpin. Resistance induced...

The antifungal activity of sodium silicate on Fusarium sulphureum and its inhibitory effect on dry rot of potato tubers were investigated. Sodium silicate strongly inhibited spore germination and mycelial growth. Morphological changes in sodium silicate-treated hyphae such as mycelium sparsity and asymmetry, hyphal swelling, curling, and cupped sha...

The antifungal activity of chitosan on Fusarium sulphureum in relation to the inhibitory effect on dry rot of potato tuber was investigated. The results showed spore germination and mycelial growth of F. sulphureum were inhibited by chitosan treatment and the inhibitory effect was highly correlated with chitosan concentration used in this study. Mo...

The effects of chitosan treatment and inoculation on dry rot in tubers and slices of potato were studied. The results showed that chitosan treatment significantly reduced the lesion diameter of potato inoculated with Fusarium sulphureum. The treatment at 0.25% showed the best effect. Chitosan at 0.25% increased the activities of peroxidase and poly...

Induced resistance was studied in muskmelons (cv. Yindi) inoculated Trichothecium roseum with postharvest 1,2,3-benzothiadiazole-7-carbothioic acid S-methyl ester (ASM) (100 mg L−1) or harpin (50 mg L−1) treatment. Both ASM and harpin significantly reduced lesion diameter in inoculated fruit. Lesion diameter was limited in the treated and untreated...

Ethanol-dichloromethane crude extract from peel of pear (Pyrus bretschneideri Rehd. cv. Pingguoli) was separated by thin layer chromatographic plates and bioassayed with conidia of Alternaria alternata. The inhibition zones differed significantly in retention factor (Rf) at expanding stage, harvest time and after 100 days of cold storage. The compo...

Purpose of review: Data on rheological properties of food products are essential for product development and design, as well as evaluation of process equipment such as pumps, piping, heat exchangers, evaporators, sterilisers and mixers. Food puree rheology is important not only for optimising or designing their handling and thermal processing equip...

Alternaria rot of Pingguoli pear occurred after latent infection. Fruit surfaces were asymptomatic within 60 days storage under cold condition (0°C, RH 85–90%), but black-grey hyphae could be seen in the lenticels or calyx tube of Pingguoli pear after 90 days of storage. The tissue collapsed and resulted in visible black spots as the hyphae spread...

Acibenzolar-S-methyl (ASM) is a chemical activator of systematic resistance in many plants. The effect of postharvest dipping with different concentrations of ASM was studied in Hami melons (cvs. New Queen and 8601). A concentration at 200 mg/L was the most effective treatment for reducing decay severity caused by Alternaria alternata, Fusarium sem...