Pest Of Legumes Research Articles

International standards for leguminous crops and methods of microbiological validation of laboratory researches

The article presents an analysis of the current international standards for leguminous crops and methods of microbiological validation based on laboratory studies. Quality and safety standards are considered at different stages of the food chain - from producer to consumer. Standards containing technical recommendations on optimal storage, loss prevention, preservation of product quality (ISO 6322 “Cereals and legumes. Storage”); standards for the detection of pests of legumes, including sampling methods and rapid methods for determining the time of infection (ISO 663 “Cereals and legumes - Determination of latent insect infestation”); determination of contaminants and impurities and suitability for use (ISO 605 “Leguminous crops - Determination of impurities, sizes, odors, insects, species and varieties - Test methods”); Determination of moisture content of legumes during the post-harvest period and storage period (ISO 24557 Legumes - Determination of moisture content). Analyzed a new series of international standards ISO 16140, consisting of 6 parts, in the field of microbiological validation of the food chain. A comparative assessment of the standards providing for procedures and criteria for selecting methods of microbiological testing in laboratories is given. The protocols for checking reference methods of standards and validated alternative methods, protocols for laboratory studies to identify qualitative and quantitative microbiological indicators, as well as methods for confirmation and typing are described in detail. The procedures for the practical application of laboratory quality control of the tests performed have been comprehensively analyzed.

Development of a Polymerase Spiral Reaction-Based Isothermal Assay for Rapid Identification of Thrips palmi.

Thrips cause considerable economic losses to a wide range of food, feed, and forest crops. They also transmit several plant viruses. Being cryptic, it is often difficult to distinguish thrips species in crops and large consignments by conventional methods. Melon thrips (Thrips palmi Karny, Thysanoptera: Thripidae) is an invasive insect pest of vegetables, legumes, and ornamentals besides being vector to several viruses. It poses a threat to domestic and international plant biosecurity and can invade and establish in new areas. Here, we report a polymerase spiral reaction (PSR)-based isothermal assay for rapid, sensitive, specific, low-cost, and on-site detection of T. palmi. To the best of our knowledge, this is the first application of PSR in the identification of any insect species. A primer pair designed based on 3′-polymorphism of mtCOIII region can specifically identify T. palmi without any cross-reactivity with predominant thrips species. The assay uses crude lysate of a single thrips saving time and reagents involved in nucleic acid extraction. The presence of T. palmi is visualized by the appearance of bright fluorescence under ultraviolet light or a change in reaction color thus avoiding gel electrophoresis steps. The entire process can be completed in 70 min on-site using only an ordinary water bath. The assay is sensitive to detecting as little as 50 attograms of T. palmi template. The assay was validated with known thrips specimens and found to be efficient in diagnosing T. palmi under natural conditions. The described method will be useful for non-expert personnel to detect an early infestation, accidental introduction to a new area, restrict the spread of diseases and formulate appropriate management strategies.

Antennal transcriptome analysis of chemosensory genes in the cowpea beetle, Callosobruchus maculatus (F.).

Olfaction, one of the most important sensory systems governing insect behavior, is a possible target for pest management. Therefore, in this study, we analyzed the antennal transcriptome of the cowpea beetle, Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae: Bruchinae), which is a major pest of stored pulses and legumes. The de novo antennal RNA-seq assembly results identified 17 odorant, 2 gustatory, and 10 ionotropic receptors, 1 sensory neuron membrane protein, and 12 odorant-binding and 7 chemosensory proteins. Moreover, differential gene expression analysis of virgin male and female antennal samples followed by qRT-PCR revealed 1 upregulated and 4 downregulated odorant receptors in males. We also performed homology searches using the coding sequences built from previously proposed amino acid sequences derived from genomic data and identified additional chemosensory-related genes.

Monitoring of legume pests and diseases

Monitoring of legume pests and diseases

Differences in the behaviour of model and non-model species of ants in interactions with the pod-sucking myrmecomorphic bug, Riptortus linearis (Hemiptera: Alydidae)

Ants are common invertebrate models of many myrmecomorphic arthropods since they are unpalatable and pose a threat for many species. Natural habitats harbour a diverse community of different species of ants and their mimics. The myrmecomorphic bug, Riptortus linearis uses a variety of extrafloral nectary-bearing or hemipteran-harbouring legumes as host plants, which are also visited by various sugar-loving species of ants. In the present study, we investigated the responses of the ant-mimicking and non-mimicking stages of the pod-sucking bug, Riptortus linearis, its ant model, Camponotus compressus and a co-occurring ant, Crematogaster subnuda, during experimental encounters, under laboratory conditions. Cr. subnuda ants were much more aggressive than Ca. compressus ants towards the myrmecomorphic bug. However, the pod-sucking bug exhibited similar responses to both of the species of ants. More importantly, Ca. compressus ants did not bite the first instar nymph of the bug. The results of this study show that the non-model ant was significantly more aggressive than the ant model towards different stages of R. linearis. These results have important implications for the management of the pod-sucking bug, R. linearis, which is an important pest of many legumes.

Bean Flower Thrips Megalurothrips usitatus (Bagnall) (Insecta: Thysanoptera: Thripidae)

The Featured Creatures collection provides in-depth profiles of insects, nematodes, arachnids and other organisms relevant to Florida. These profiles are intended for the use of interested laypersons with some knowledge of biology as well as academic audiences. Megalurothrips usitatus (Bagnall, 1913) is a small sized (3-4 mm) insect in the order Thysanoptera and family Thripidae, commonly known as bean flower thrips, oriental bean thrips, and Asian bean thrips. It is an important economic pest of legumes. Megalurothrips usitatus was first reported in the USA in Florida in 2020 (Soto-Adames, F. N. 2020).

Bionomics of transverse ladybird beetle, Coccinella transversalis on cowpea aphid, Aphis craccivora

Cowpea aphid, Aphis craccivora Koch is one of the important pests of legumes. It is a cosmopolitan and polyphagous pest causing 30-35% damage to vegetable crops globally. Chemical control of this pest is not only expensive but also has deleterious effects on human health, environment and non-target organisms. Biological control is one of the most important components of integrated pest management to achieve eco-friendly and sustainable management of crop pests. Coccinellid predator, Coccinella transversalis Fab. is an efficient predator known for its appetite on cowpea aphid under vegetable ecosystem. With this background, we conducted a study on biology, morphometric and functional response of C. transversalis on cowpea aphid under laboratory conditions (27±1°C and 65±5% RH) at Biological Control Lab, ICAR-Indian Agricultural Research Institute, New Delhi, during 2016-17. Type of functional response was determined through polynomial logistic regression of proportion of prey consumption to the density of prey. Functional response parameters were obtained by fitting the data to the Holling's and Roger's equations. Total life span of male and female was ranged from 47-64 and 60-71 days, with a mean of 56±6.2 and 66±3.9 days, respectively. Both male and female of C. transversalis were found to exhibit Type II functional response. Female has showed high attack rate (1.99±0.141) compared to male (1.90±0.088) with maximum prey consumption of 84.41 and 80.51 aphids/day, respectively. Handling time obtained for males (0.0124 day) was higher than females (0.0118 day).

Diversity and geographic variation of endosymbiotic bacteria in natural populations of the pea aphid (Acyrthosiphon pisum) in China

• We firstly characterized symbiont communities and diversity of the pea aphid in China. • The obligate symbiont, Buchnera , was present in all aphid samples. • Four facultative symbionts ( Serratia , Hamiltonella , Regiella , and Rickettsia ) showed a significant geographic variation. • Bacterial communities of the Chinese pea aphid populations were mainly influenced by environmental factors. Bacterial symbionts in aphids are known to benefit the insect host and associated with aphid’s ecological adaptation. The pea aphid ( Acyrthosiphon pisum ), an important legume pest worldwide, carries at least eight endosymbionts, providing a model system to study insect–bacteria interactions. However, species diversity and geographic variations of endosymbionts are unknown in Chinese populations; therefore, we characterized symbiont communities and diversity of 27 pea aphid samples from 13 geographic populations of China. Via amplicon high-throughput sequencing and diagnostic PCR, we found that bacterial communities of Chinese populations were dominated by Proteobacteria and Firmicutes. Among eight known endosymbionts, five ( Buchnera , Serratia , Hamiltonella , Regiella , and Rickettsia ) were detected by both methods, with a specific geographical distribution. The obligate symbiont, Buchnera , was present in all aphid samples, while the four facultative symbionts showed a significant geographic variation. Each population was randomly infected with distinct endosymbionts, ranging from three to five species. Serratia and Rickettsia showed relatively higher abundance in central regions of China, Regiella was predominant in eastern and western China, whereas Hamiltonella showed an extremely low abundance and was absent in four populations. Samples grouped by altitudes showed a significant diversity difference, whereas there was no significant difference between red and green body colors. Bacterial community structures of the Chinese pea aphid populations were mainly influenced by environmental factors, other than body colors. These data can guide the development of potential biocontrol techniques against this aphid.

BIOPESTICIDES: ALTERNATIVES FOR MANAGEMENT OF CALLOSOBRUCHUS MACULATUS

ABSTRACT Among insect pests of stored legumes, Callosobruchus maculatus is ranked as the most important with seed loss as high as 60-100% having been reported. Chemical control using synthetic insecticides is usually advocated. These chemicals can have undesirable side effects including human and animal health concerns, development of insecticide resistance andenvironmental contamination. Biopesticides, especially the use of semiochemicals, botanical extracts and microbial pesticides provide a sustainable and innovative alternative to the sole use of synthetic insecticides. The components of the sex pheromone for C. maculatus have been identified as 3-methyleneheptanoic acid, (Z)-3-methyl-3-heptenoic acid, (E)-3-methyl-3- heptenoic acid, (Z)-3-methyl-2-heptenoic acid and (E)-3-methyl-2-heptenoic acid, nonanedioic acid and 2,6-dimethyl-1, 8-octanedioic acid. The use of semiochemicals and pheromones in particular can allow for better monitoring of C. maculatus in warehouses and other grain storage facilities. In small scale situations, use of pheromones for mass trapping of C. maculatus may be feasible and should be advocated under such circumstances. The use of semiochemicals forenhancement of the effectiveness of biological control agents of C. maculatus has been explored. Preliminary research indicates that it may be possible to use semiochemicals to manipulate the behavior and increase the efficacy of natural enemies of storage pests including C. maculatus. Various plants and their extracts have been investigated for use in management of all stages of C. maculatus. Several of these have repellent, antifeedant, contact toxicity and/or oviposition deterrent properties. Essential oils derived from various plant parts are particularly effective as fumigants due in large measure to their volatile nature. Use of botanical extracts is particularly appealing for resource poor farmers from developing countries as both the plant materials, as well as most of the techniques used for extraction of the active components are readily available to them. Biological control using microbial agents is another viable strategy for management of C. maculatus. A number of entomopathogenic fungi in particular have been isolated, tested and their efficacy against the cowpea seed beetle demonstrated. Culture and formulation preparation of these fungi and other microbial agents can also be done at the farm level. The combination of several biopesticidal options offers sustainable and ecologically appropriate alternatives to the sole use of synthetic insecticides for management of C. maculatus and these are explored in the current chapter.

Priming Soybean cv. Primus Leads to Successful Systemic Defense Against the Root-Lesion Nematode, Pratylenchus penetrans.

Root lesion nematodes, Pratylenchus penetrans, are major pests of legumes with little options for their control. We aimed to prime soybean cv. Primus seedlings to improve basic defense against these nematodes by root application of N-3-oxo-tetradecanoyl-L-homoserine lactone (oxo-C14-HSL). The invasion of soybean roots by P. penetrans was significantly reduced in plants that were pre-treated with the oxo-C14-HSL producing rhizobacterium Ensifer meliloti strain ExpR+, compared to non-inoculated plants or plants inoculated with the nearly isogenic strain E. meliloti AttM with plasmid-mediated oxo-C14-HSL degradation. The nematodes were more clustered in the root tissues of plants treated with the AttM strain or the control compared to roots treated with the ExpR+ strain. In split-root systems primed on one side with strain ExpR+, root invasion was reduced on the opposite side compared to non-primed plants indicating a systemic plant response to oxo-C14-HSL. No additional local effect was detected, when inoculating nematodes on the ExpR+ primed side. Removal of oxo-C14-HSL after root exposure resulted in reduced root invasion compared to non-primed plants when the nematodes were added 3, 7, or 15 days later. Thus, probably the plant memorized the priming stimulus. Similarly, the plants were primed by compounds released from the surface of the nematodes. HPLC analysis of the root extracts of oxo-C14-HSL treated and untreated plants revealed that priming resulted in enhanced phytoalexin synthesis upon P. penetrans challenge. Without root invading nematodes, the phytoalexin concentrations of primed and non-primed plants did not significantly differ, indicating that priming did not lead to a persistently increased stress level of the plants. Upon nematode invasion, the phytoalexins coumestrol, genistein, and glyceollin increased in concentration in the roots compared to control plants without nematodes. Glyceollin synthesis was significantly more triggered by nematodes in primed plants compared to non-primed plants. The results indicated that the priming of soybean plants led to a more rapid and strong defense induction upon root invasion of nematodes.

Diversification, selective sweep, and body size in the invasive Palearctic alfalfa weevil infected with Wolbachia

The alfalfa weevil Hypera postica, native to the Western Palearctic, is an invasive legume pest with two divergent mitochondrial clades in its invading regions, the Western clade and the Eastern/Egyptian clade. However, knowledge regarding the native populations is limited. The Western clade is infected with the endosymbiotic bacteria Wolbachia that cause cytoplasmic incompatibility in host weevils. Our aim was to elucidate the spatial genetic structure of this insect and the effect of Wolbachia on its population diversity. We analyzed two mitochondrial and two nuclear genes of the weevil from its native ranges. The Western clade was distributed in western/central Europe, whereas the Eastern/Egyptian clade was distributed from the Mediterranean basin to central Asia. Intermediate mitotypes were found from the Balkans to central Asia. Most Western clade individuals in western Europe were infected with an identical Wolbachia strain. Mitochondrial genetic diversity of the infected individuals was minimal. The infected clades demonstrated a higher nonsynonymous/synonymous substitution rate ratio than the uninfected clades, suggesting a higher fixation of nonsynonymous mutations due to a selective sweep by Wolbachia. Trans-Mediterranean and within-European dispersal routes were supported. We suggest that the ancestral populations diversified by geographic isolation due to glaciations and that the diversity was reduced in the west by a recent Wolbachia-driven sweep(s). The intermediate clade exhibited a body size and host plant that differed from the other clades. Pros and cons of the possible use of infected-clade males to control uninfected populations are discussed.

Urticaria, Anaphylaxia and Asthma from Contact with Work Air in Farmers and Agronomists Due to Bruchus Pisorum

Background: There are few reports of contact urticaria from the inhalation of allergens from legume pests. Objective: To study the origin of an outbreak of contact urticaria, asthma and anaphylaxis in farmers and agronomists who work handling dried peas. Method: Allergenic extracts composed of Bruchus lentis and B. pisorum, healthy peas, peas treated with aluminum phosphide and parasitized peas were used for in vivo tests (prick-test, oral challenge and bronchoprovocation) in affected patients and in five controls. with a history of atopy from other legumes. In addition, patch testing with live Bruchus pisorum, patch testing with more common insecticides, molecular component analysis, and Ig-E immunodetection were carried out. Results: Positive responses were found for the prick-test and the bronchoprovocation test to extracts of parasitized peas and B. pisorum, but the oral challenge was negative. A common 25 kDa band for infested peas and a 30 kDa band for infested pea and B. pisorum body was detected in all patients. The response for pea allergens was negative for all patients, unlike controls with a history of allergy to lentils and peanuts. Conclusion: It was determined that B. pisorum is a cause of symptoms of immediate hypersensitivity mediated by Ig E by inhalation of the allergen or by puncture of spicules or mushrooms of B. pisorum.

Temporal and age-related variations in calling and mating patterns of the Indian population of spotted pod borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae)

Maruca vitrata is an important pantropical and polyphagous insect pest of grain legumes. The adult emergence pattern and temporal variations in the calling and mating behaviour of M. vitrata across ages were studied. Observations revealed that adult emergence was not influenced significantly by sex, but by the time of the day. Calling activity is a strong determinant of male mating success in insects. An age-dependent female calling pattern was observed. Females seldom called on their day of emergence, calling percentage was low to nil in the first four hours of scotophase but reached a peak in the fifth hour. The calling patterns of females of different ages were similar except that there were two peaks of calling for 3 and 4 days old females. Like calling, the mating pattern was also age-dependent, i.e. M. vitrata mating frequency was maximum at 3-days of age and thereafter decreased gradually with age. The highest mating frequency (30.83%) was observed at 2200 h for 3-day-old moths. The current study revealed that age dependant and distinct patterns in female calling, synchronous male responsiveness leading to mating in M. vitrata. The output of the study could be utilized in various aspects of M. vitrata semiochemical based research.

A very curious larder – Insects from post-medieval Skálholt, Iceland, and their implications for interpreting activity areas

Fossil insect assemblages from post-medieval Skálholt, the oldest episcopal see in Iceland, provide new information about indoor environments and the specific use of a structure which according to historical information was listed as a larder attached to the episcopal school. The assemblages recovered also provide information on the background fauna which comprises of species related to turves, used for building construction and indicating storage of peat. In addition to the introduced Sitophilus granarius, the granary weevil, a new pest, Callosobruchus maculatus which is a pan-tropical and subtropical field and storage pest of legumes, and a rarely introduced species in Iceland even today, were also recovered from the site. In view of the nature of the assemblages, these were probably accidental introductions into the room, perhaps in faeces. The historical record provides information about the life history and events at Skálholt and data about school supplies including imports of stored products to Iceland during this period. In addition, the high numbers of sheep keds, Melophagus ovinus, combined with high numbers of human lice, Pediculus humanus, point to the washing of wool and clothing in urine to get rid of ectoparasites. Intra-site comparisons and a review of all Icelandic archaeological sites suggest a clear correlation between the presence of ectoparasites and wool preparation and cleaning. The results from Skálholt clearly show that rooms and specific spaces in post-medieval buildings could have multiple functions, not only the one assigned to them in the historical record.

Emergence ofMaruca vitrataas a Major Pest of Food Legumes and Evolution of Management Practices in Asia and Africa

Legume pod borer, Maruca vitrata, has emerged as a major pest on food legumes in Asia and Africa. It is an oligophagous pest, feeding on over 70 species in Fabaceae. We examine the species complex in Asia, Africa, Oceania, and the Americas, with an emphasis on molecular taxonomy. Studies on pheromone production and perception suggest the existence of pheromone polymorphism, especially in Asia and Africa. No Maruca-resistant varieties are available in the major food legumes including cowpea, pigeonpea, mungbean, and yard-long bean. Legume growers use chemical pesticides indiscriminately, leading to the development of pesticide resistance. However recent developments in habitat management, classical biocontrol with more efficient parasitoids, biopesticides, and judicious use of insecticides pave the way for sustainable management of M. vitrata, which can reduce the pesticide misuse. Active engagement of the private sector and policy makers can increase the adoption of integrated pest management approaches in food legumes.

Research of Aphididae of Cereals and Legumes of the Northeastern Ukraine.

Introduction. The article presents the results of research to establish the species composition of aphids –pests of cereals and legumes of agricultural farm of Kharkov region and analyzes their ecological and biological features. The research was conducted for several years in the spring and summer in the Kupyansk district, Kharkov region. A study of constant changes in the species composition of aphidofauna and recommendations for regulating the number of pests is very relevant today.Purpose.The purpose of the study is to investigate the composition of aphidofauna species of cereals and legumes today and to study the dynamics of the abundance of common species in the field of research.Methods.Inspection of infected plants, determination of the degree of colonization by aphids of each plant. Collecting aphids and determining their species.Results. Thirteen species of aphids of the family Aphididae have been collected and identified. Among the cultivated plants, fields sown with 14 species of cereals and legumes were surveyed. By type of food, certain species of aphids are conditionally divided into oligophages (5 species) and polyphages (8 species). In the aphidofauna of Ukraine, monoecious (non-migratory) life cycles are typicalfor 6 species (46% of the total number), dioecious (migratory) for 7 species (54%) of aphids. The largest number of aphid colonies was recorded on cereals and legumes at the edges of fields bordering on separate strips of woody-shrub and herbaceous vegetation, which serves as an additional forage base or primary host in the dioecious life cycle of some species. Significant aphid damage to cereals was observed during the end of milky –the beginning of waxy ripeness of grain, on the tops of shoots on corn, and in legumes –during the entire growing season on young leaves and stems. As for climatic factors, there was an increase in the number of aphids on cereals in hot dry weather, and on legumes –in moderately warm and humid. Heavy rains suppressed the rapid reproduction and development of all species of aphids. Conclusion.As a result of research, 13 species of aphids of the family true aphids Aphididae were found and identified.The most numerous were polyphagous aphids: the large cereal aphid Sitobion avenae Fabricius, 1775, the common cereal aphid Schizaphis graminum Rondani, 1852, the barley aphid Brachycolus noxius Mordvilko, 1913, the bird-cherry-cereal aphid Rhopalosiphum padi Linnaeus, 1758, elm-cereal, or corn aphid Tetraneura ulmi Linnaeus, 1758, beet-leaf aphid Aphis fabae Scopoli, 1763, pea aphid Acyrthosiphon pisum Harris, 1776.Key words: aphids; aphid fauna; cereals; legumes; oligophagеs; polyphagеs

Potential Threat of Bruchids on Soybean Production in Sub-Saharan Africa

Soybean production in sub-Saharan Africa (SSA) has been increasing in recent years in part due to the efforts of several national and international research agencies, including the Soybean Innovation Laboratory (SIL). SIL’s mission to increase utilization and production of soybean in SSA has led to several facets of research including cultivar development to increase yield through the Pan-African Soybean Variety Trials (PATs). Several abiotic and biotic stresses can decrease yield, including pathogens and pests that attack seed. While evaluating seed lots from 32 PAT locations, we identified bruchids and/or bruchid-damaged seed in nine locations in four countries (Cameroon, Malawi, Mozambique, and Rwanda). The most severe damage and infestation was recorded in Bwanje, Malawi, with 28 of the 40 seed lots infested. Seed damage ranged from 0.6 to 100% among the 28 infested seed lots. Adult bruchids discovered at the Bwanje location were identified as Callosobruchus chinensis, or the Chinese bruchid. No adults were found in other locations. Bruchids are a destructive storage pest of legumes, and monitoring the different species attacking soybean will help researchers and producers understand the potential threat of bruchids to soybean production in SSA as well as help implement the best management practices.

Plant Resistance to Cereal and Food Legume Insect pests in North Africa, West and Central Asia: Challenges and Achievements.

Even though host plant resistance has long been recognized as the foundation of integrated pest management, research in North Africa, West and Central Asia only started in 1980. The recent use of Focused Identification of Germplasm Strategy has increased the chance of finding sources of resistance to cereal and food legume pests. The resistant sources have been successfully used in breeding programs to develop resistant germplasm to key cereal and legume pests. The first major locus associated with resistance to Sunn pest at vegetative stage was identified in bread wheat as were two new loci for Hessian fly resistance from Triticum dicoccum and T. araraticum. Combined sources of resistance to several pests have been identified in alien translocation wheat lines.

Interactions Between Two Invertebrate Pathogens: An Endophytic Fungus and an Externally Applied Bacterium.

The members of family Noctuidae exist in diverse environments and many species from this group are of agriculture importance, particularly Helicoverpa spp. Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) is a major pest of many legumes and cereal crops. Due to environmental and regulatory concerns, safe alternatives to broad spectrum chemical insecticides are needed for the control of key noctuid pests such as H. armigera. A strain of Beauveria bassiana (Cordycipitaceae: Hypocreales) was evaluated for its ability to colonize endophytically in chickpea plants, and its effectiveness against second (L2) and fourth (L4) larval instars of H. armigera. B. bassiana was inoculated to chickpea plants through injection and endophytic establishment was confirmed by re-isolating the fungi from leaf samples. A detached leaf assay was used to evaluate pathogenicity. Bacillus thuringiensis was also applied to both larval stages through leaf dip method. In a novel approach, combined treatments of bacteria and endophytic fungi were compared with single-pathogen treatments. Relative to the single treatments, the combined pathogen treatments exhibited an increase in larval mortality, and decrease in pupation, adult emergence and egg eclosion. Specifically, synergistic effects on mortality were observed when larvae were exposed to simultaneous application of B. bassiana (1 × 108 conidia ml–1) with B. thuringiensis (0.75 μg ml−1). Both instars exhibited varying level of growth, development, frass production, diet consumption and fecundity when exposed to the chickpea leaves inoculated with endophytic B. bassiana and dipped with sub-lethal doses of B. thuringiensis. These findings indicate that the integrated application of endophytic colonized B. bassiana and B. thuringiensis can be effectively used against H. armigera.

Insecticidal activity of the extract, fractions, and pure steroidal saponins of Trillium govanianum Wall. ex D. Don for the control of diamondback moth (Plutella xylostella L.) and aphid (Aphis craccivora Koch).

Plutella xylostella L. is the major pest of crucifers globally, causing significant yield loss. Aphis craccivora Koch is the main sucking pest of legumes that transmit viral diseases, leading to economic yield reduction. To minimize loss due to pests, farmers/growers use synthetic insecticides frequently for their control, which led to insecticide resistance, detrimental to natural enemies of pest, environment, etc. Therefore, in this study, the insecticidal activity of plant extract, fractions, and pure steroidal saponins from Trillium govanianum was evaluated for their bio-efficacy against targeted pests. Parent extract was found more effective (LC50 = 1541.2 mg L-1 ) against larvae of P. xylostella after 96 h than n-butanol, n-hexane, and ethyl acetate fractions (LC50 = 3030, 3578 and 3878.1 mg L-1 , respectively). For A. craccivora, ethyl acetate fraction (LC50 = 2186.3 mg L-1 ) was most effective after 96 h than n-hexane fraction (LC50 = 2234.6 mg L-1 ), n-butanol fraction (LC50 = 2696.3 mg L-1 ) and parent extract (LC50 = 3709.1 mg L-1 ). Among pure molecules, govanoside B was found more effective (76% mortality, LC50 = 3279.5 mg L-1 ) followed by borassoside E (74%, LC50 = 3467.1 mg L-1 ) against A. craccivora after 96 h. Parent extract/fractions of T. govanianum showed promising efficacy against larvae of P. xylostella and A. craccivora. Further, field study is required for its bio-efficacy against targeted pests for validation and formulation development.