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Crop Losses due to insect pests: Global and Indian Scenario
... Agricultural research emphasizes models that consider a few parameters, from qualitative crop injuries to quantitative losses, from pre-to post-harvest damage, even though crop loss assessments are notoriously difficult to execute. The current crop losses due to insects to major crops in India [2] are shown in Table 1. ...
... Table 1. Current crop losses due to insects to major crops in India (Source: [2]). ...
... In India, the amount of money spent on pesticides is estimated around annual US$650, which is mainly intended to control bollworm and sucking pest of cotton. Dhaliwal et al. (2015) recorded that Indian farming is suffering from a huge loss of US$36 billion (16.8% in terms of percentage of yield decline) annually owing to insect pest incidence. It has also been recorded that percentage of yield loss of crops because of insect pest attack in major crops rose from 7.2% to 23.3% during the period between pre-green revolution era (1960s) and postgreen revolution era (2000s). ...
... It has also been recorded that percentage of yield loss of crops because of insect pest attack in major crops rose from 7.2% to 23.3% during the period between pre-green revolution era (1960s) and postgreen revolution era (2000s). Additionally, due to the adoption of Bt cotton in Indian agriculture (occupying more than 95% of cotton producing areas), the yield loss due to insect pest is estimated at around 30% (Dhaliwal et al., 2010(Dhaliwal et al., , 2015. ...
Insect-parasitic nematodes belonging to the families Heterorhabditidae and Steinernematidae have developed symbiotic relationships with bacteria belonging to the genera Photorhabdus and Xenorhabdus, respectively. The nematode-bacteria complex can kill the host insect within 24-48 h via septicemia or toxaemia. Bacteria (which lives in the nematode gut) enter the host through its nematode partner, and the nematode relies on bacteria for nutrition from liquefied host tissue. The bacteria kill the insect by using its arsenal of toxins and secondary metabolites. These nematodes have long been utilized as insect biological control agents, but their short shelf life and demand for a certain temperature and moisture range for field performance have limited their commercial use. A number of protein toxins from distinct Indian strains of Photorhabdus spp. were identified in our laboratory. The biological activity of candidate toxins was tested in Galleria mellonella, a model insect, and then in agriculturally important insects such as Heliocoverpa armigera, Spodoptera litura, S. exigua and S. frugiperda. When toxins was administered orally either via artificial diet or force-feeding, the toxins had shown catalytic activity on the insect gut epithelial cells and moved to hemocoel by proteolytically cleaving the basement membrane lining in the gut-hemocoel barrier. Following that, a cytotoxic effect on immunocytes or hemocytes was seen, similar to apoptosis or cell death. Toxins also had an immunomodulatory effect as documented by the elevated phenoloxidase activity in the hemolymph. These gut-active toxins putatively interact with different insect midgut receptors. Currently, we are pursuing RNAi knockdown of receptors to establish their role in disease development. The novel insecticidal toxins characterized from Photorhabdus spp. may provide a greater diversity of biotoxins at disposal for pest management either via transgenic mean or bio-protectant formulations.
... Although protected agriculture and vertical farming are rapidly being adopted, insect pests are emerging as a major problem due to the conducive environment maintained inside the protected structures (Phani, Khan & Dutta, 2021). Indian agriculture suffers heavily due to a multitude of insect pest occurrence including noctuid lepidopteran pests such as Spodoptera litura and S. frugiperda (Dhaliwal, Jindal & Mohindru, 2015;EFSA Panel on Plant Health, 2019;Suby et al., 2020). The polyphagous S. litura can infect over 100 crops and are widely distributed across tropical and subtropical Asia including India, China and Japan (Cheng et al., 2017). ...
Background: A multitude of Cry toxins (secreted by Bacillus thuringiensis or Bt) has been deployed globally either via transgenic mean or bio-pesticidal formulations in order to manage insect pests. However, Bt resistance development in insects is emerging as a major concern. To avoid this problem, multiple gene pyramiding or protein-engineered chimeric toxin-based strategy has been analyzed.
Methods: In the present study, one such chimeric toxin Cry1AcF (contain the swapped domains of Cry1Ac and Cry1F) was used to investigate its in vivo pathogenesis process in lepidopteran pests Spodoptera frugiperda and S. litura. A number of biochemical and molecular analysis were performed.
Results: Oral ingestion of Cry1AcF caused greater toxicity in S. frugiperda than S. litura with larvae displaying increased hemolymph melanization. Histopathology of the midgut transverse sections exhibited Cry1AcF-induced extensive gut damage in both the test insects followed by cytotoxicity in terms of reduced hemocyte numbers and viability. Elevated hemolymph phenoloxidase activity indicated the immune-stimulatory nature of Cry1AcF. In order to analyze the role of gut receptor proteins in Cry1AcF intoxication in test insects, we performed RNAi-mediated silencing using bacterially-expressed dsRNAs of individual receptor-encoding genes including CAD, ABCC2, ALP1 and APN. Target-specific induced downregulation of receptor mRNAs differentially altered the insect susceptibility to Cry1AcF toxin in our study. The susceptibility of ALP1 and APN dsRNA pre-treated S. frugiperda was considerably decreased when treated with Cry1AcF in LD 50 and LD 90 doses, whereas susceptibility of CAD and ABCC2 dsRNA pre-treated S. litura was significantly reduced when ingested with Cry1AcF in different doses. CAD/ABCC2-silenced S. frugiperda and ALP1/APN-silenced S. litura were vulnerable to Cry1AcF alike of control larvae. In conclusion, our results indicate ALP1/APN and CAD/ABCC2 as the functional receptor for Cry1AcF toxicity in S. frugiperda and S. litura, respectively.
... Recently, it posed a serious risk of invasion in the Americas, Australia, China, Europe, New Zealand and West Africa due to congenial environment, host crops and agronomic practices (Yonow et al., 2017). It is an established pest of maize, sorghum, sugarcane and rice, and has also been recorded from small millets and wild grasses, causing 18 to 25% yield losses in maize and sorghum in Asia and Africa (Dhaliwal et al., 2015). The presence, abundance and intensity of infestation by C. partellus is influenced by both biotic and abiotic factors, wherein the morphological, behavioural, physiological and bioecological variation makes it to survive under diverse and adverse agroecological conditions. ...
Spotted stem borer, Chilo partellus (Swinhoe) is one of the most widely distributed pests of coarse cereals, causing 18 to 25% yield losses in Asia and Africa. The larvae of C. partellus pass through hibernation under North Indian and aestivation under South Indian conditions. Although diapause helps C. partellus in adapting under unfavorable conditions, there is 17.2 to 28.3% and 7.0 to 33.7% population sacrifice during hibernation and aestivation, respectively. The population heterogeneity in C. partellus could be due to hibernation or aestivation, wherein the models, Ikemoto & Takai (linear), and Lactin-1 and Lactin-2 (non-linear) are efficient for describing temperature-dependent development and estimating the temperature thresholds of diapausing larvae. This helps in predicting the occurrence, seasonal emergence, number of generations and population dynamics of the pest. Diapause results in differential regulation of hormonal and biochemical profiles, impose deleterious effects on the post-diapause development, reproductive physiology and population growth of C. partellus. The diapause, developmental and morphometric traits in C. partellus are governed by overdominance gene effects which mainly depend on parental diapause history. Four different biotypes of C. partellus viz., Hisar, Hyderabad, Parbhani and Coimbatore exist in India, suggesting that sorghum and maize genotypes need to be tested against these four populations to identify stable sources of resistance. The whole genome sequencing will be useful for understanding mode of action of different insecticides, mechanisms of detoxification and designing target-specific insecticides to develop appropriate strategies to manage C. partellus for sustainable crop production. The temporal distribution of mating systems among adults of diapause, non-diapause and/or ecologically diverse populations, and their behavioral and physiological consequences under a given demographic framework could be rewarding, and aid in to devising appropriate mating disruption techniques to suppress C. partellus population.
... To achieve higher crop yields and agricultural productivity, pest problems are considered a major problem. The loss of agricultural productivity of crops due to insect pests was estimated to be 15.7% (Dhaliwal et al. 2015). Recently, a valuable tool for crop protection or pest management has been based on the biological control of pests via microbial pathogens, such as bacteria, nematodes, viruses, and fungi (Anand et al. 2009). ...
Recently, the excessive use of chemical pesticides for pest management has led to environmental contamination, and the interest of consumers has diverted towards the use of biopesticides to control plant pests and plant diseases. The entomopahogenic fungus Beauveria bassiana plays a key role in the management of various veterinary, forestry, and agricultural arthropod pests. However, the use of entomopathogenic fungi as biocontrol agents is less expensive and safer. Beauveria formulated in liquid or dry formulations with large numbers of aerial conidia are typically deployed in a wide range of applications in a chemical paradigm. Solid-state fermentation has emerged as an appropriate technology for the mass production of Beauveria to yield hydrophobic aerial conidia, the principal active ingredients of mycoinsecticides. An effective production methodology that can be easily adopted involves the use of different media such as wheat bran, rice bran, Sabouraud dextrose agar (SDA), and sorghum, which were used as substrates for mass multiplication of B. bassiana. Organic media, nonsynthetic media, and the biomass of fungal grain media can also be used for production. The economics of B. bassiana were evaluated based on the final yield. However, worldwide production of fungal spores that demand low inputs was carried out using simple technologies while considering the aspect of production and cost-benefit analysis as well as marketing of B. bassiana, targeting the basis of entrepreneurship. Hence, this book chapter was designed to provide an overview of the mass cultivation of the entomopathogenic fungus B. bassiana on locally available agricultural and industrial waste to decrease the production cost and to increase the cost-benefit ratio for the production of virulent spores, i.e., solid and liquid media, and to accelerate the commercialization of B. bassiana.Keywords
Beauveria bassiana
MycoinsecticideCost-benefit analysisBiocontrolEntomopathogenic fungi
... It has been reported that average losses of up to 90% of the total crop production happened due to the infestation of weed (Meena, 2015). Similarly average losses of up to 19% have been reported due to pests (Dhaliwal et al., 2015). This leads to over use of pesticides and there may be chances of further contamination of the soil and groundwater. ...
Recent Advances in Agricultural
... However, losses because of pestiferous arthropods are often considerably higher in the Tropics that mostly include developing countries in Asia and Africa, where most of future increases in human population are expected to occur in the next 50 years. In India the highest crop losses are in Gossypium (50%), followed by Sorghum (30%) and different millets (30%), and Oryza, Zea, and various oilseeds (each 25%) (Dhaliwal et al., 2015). Farmers through the world actively use pesticides to suppress nuisance insects. ...
Integrated pest management (IPM) programmes are based on using multiple methods to maintain nuisance insects below tolerant levels in crop fields. Recent advances in IPM in developed countries have incorporated biological pesticides, microbial products, semiochemicals, and beneficial insects, but few of such programmes have been successfully implemented in developing countries, such as India. Semiochemicals play critical roles as signals in various interspecific and intraspecific interactions between insects and plants, and among interacting insects, plants, and microbes. In India IPM programmes have included mechanical, chemical, cultural, and biological management strategies. However, among these methods, biological management has its own limitations. Indian IPM scientists mostly work on individual crops, assessing damage severity by specific nuisance arthropods and the efficacy of particular management measure. However, very few government institutions or commercial companies are engaged in developing and commercializing either biological pesticides or semiochemicals. Government institutions mostly focus on research on pheromones of the pestiferous Lepidoptera and Coleoptera. Developing IPM programmes requires a clear understanding of crop-plant development, biology and population dynamics of the nuisance organisms, and the chemical and molecular interactions between the two. It also necessarily requires local knowledge of available, prevalent management tactics. Moreover, the IPM programmes have not been widely adopted in developing countries due to lack of proper knowledge and training farmers in efficient IPM practices, the need for more of human labour, and the complexity of IPM practices, all of which impede on the effective implementation of IPM programmes. In this article, we recapture the historical development of IPM efforts in India and ask whether this concept remains suitable to the present-day challenges in crop production. In this review, more specifically, those factors identified as obstacles to the more widespread adoption of IPM and ways of overcoming such barriers are discussed.
... Harmful insects, which are prevalent in agrisystems, are responsible for severe crop loss every year globally (Dhaliwal et al., 2015). Among all, aphids are one of the most harmful insects for several crops (Kalleshwaraswamy et al., 2012). ...
Aphid (Aphis gossypii) is one of the important pests of papaya crop. In this work, applications of Trichoderma harzianum and Beauveria bassiana (biocontrol agents) and malathion (insecticide) were conducted in vitro and in agrifields for testing their anti-aphid efficacy and compared their efficacy. Furthermore, the enzymatic mechanism of T. harzianum with respect to biocontrolling the pest was unearthed. The LD50 dose of T. harzianum and B. bassiana was 1.2 × 105 spores mL−1 and 1.0 × 106 spores mL−1 respectively after 48 h of administration. The LT50 of T. harzianum also exhibited a lower effective time (47.70 h) than B. bassiana (57.53 h) for the same concentration of spores applied (1 × 105 spores mL−1). The pooled data analysis of two years (2019–2020) showed that the application of T. harzianum spores in agrifields exhibited 31.75 ± 13.00a percentage of reduction of aphid population whereas malathion exhibited 23.93 ± 1.30a%, in comparison to control. The statistical analysis indicated that the application of malathion exhibited the same efficacy as T. harzianum isolate and placed in the same category. In plate detection assay, T. harzianum produced a higher hydrolytic zone for chitinase (8.0 ± 0.4 cm diameter) and protease (7.0 ± 0.4 cm diameter) enzymes, than B. bassiana (1.3 ± 0.2 cm and 1.1 ± 0.2 cm respectively). Quantitative estimation of enzymes exhibited that T. harzianum produced 299 ± 11a μg mL−1 of chitinase, 519 ± 19a μg mL−1 of protease, and 65 ± 12a μg mL−1 of PR1, and on the other hand, B. bassiana yielded 124 ± 12b, 361 ± 23b, and 29 ± 18b μg mL−1 of chitinase, protease, and PR1 respectively. It indicated that T. harzianum was superior over the B. bassiana in terms of production capacity of all three enzymes. In conclusion, all the above experimental results suggested that T. harzianum showed better aphid-killing efficacy than B. bassiana. It also suggested that T. harzianum should replace hazardous chemical pesticide (malathion) for eco-friendly biocontrol of aphids.
... A partir de la revolución verde hacia principios de este siglo las pérdidas globales por daños de plagas disminuyeron del 13,8% al 10,8% (Dhaliwal, 2015). Según Oerke (2006), entre el 2001 y 2003 las pérdidas estimadas a nivel global en rendimiento de maíz por ataque de plagas se situaban en promedio en un 9,6% y del 10,5% por competencia por malezas. ...
... Maximum net productivity, the goal sought is constrained by a number of factors of which insect pests are quite important causing more than 30% in losses. More than 100 species of insects are known to attack the rice, out of which 20 are of major economic significance estimating a yield loss to about 25% (Dhaliwal et al., 2015). Lepidopteron insect-pests are the main class of pests causing significant damage to crop yield in rice of which Pelopidas mathias (Fab.) is a predominant defoliator and one of the major pests, affecting all the rice ecosystems. ...
Paddy, Oryza sativa L. (Poales: Poaecea) is infested by a series of lepidopteran, coleopteran, hemipteran, and acarine pests in India. Of the long list, the species Rice Leaf-Roller Pelopidas mathias (Fabricius, 1798) (Lepidoptera: Hesperiidae) is one of most encountered defoliators on paddy. Here we record and describe with illustrations, a new parasitic complex comprising of two new species of parasitic wasps, viz. Brachymeria eastwoodi Binoy, sp. nov. and Sympiesis eastwoodi James & Santhosh, sp. nov. on the pupae of P. mathias from southern India. The parasitoid complexes on P. mathias are also augmented.
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