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The nature of gene action and combining ability is valuable in determining whether heterosis is fixable or predictable. Thus, to know the nature of gene action of seed cotton yield and its components and fibre quality parameters, seventeen parents (15 males and two genetic male sterile lines) and 30 F1 crosses (genetic male sterility based) were evaluated in a line x tester mating design of Asiatic cotton (Gossypium arboreum L). Sufficient variability among hybrids and their parents was found as the mean squares of genotypes for all the traits including fibre quality parameters investigated were significant. The total genetic variability was partitioned to general combining ability (GCA) and specific combining ability (SCA) effects. GCA was significant for male parents HD-123, RG-270, CISA-59, CISA-64, CISA-65, CISA-66 and LD-694 for seed cotton yield (SCY); HD-123, RG-286 and DLSA-24 for bolls per plant; HD-123, CISA-59, PAIG-8/3, DLSA-9 and LD-694 for boll weight; female parent DS-5, male parents HD-123, RG-18, CISA-65, and PAIG-8/3 for ginning outturn (GOT%); RG--270, RG-286, PAIG-8/3, DLSA-9 and LD-694 for 2.5% span length (mm); RG-286, CISA-59, CISA-66, PAIG-8/3 and LD-694 for lower micronaire value having finenessand HD-400, RG-270, RG-286, RG-341 CISA-60, CISA-66, PAIG-8/3 and LD-694 for tenacity (g/tex) which were considered as good general combiners. Similarly among 30 cross combinations, SCA was positively significant for 10 crosses for seed cotton yield, 10 crosses for boll number, 10 crosses for boll weight, 9 crosses for GOT(%), 10 crosses for 2.5% span length and 8 crosses for fibre strength (gt/tex).Cluster III of yield attributing traits, consisted of 9 crosses ( C3, C6, C18, C20, C26, C22, C23, C24, C30, and C8) showed the highest average seed cotton yield where as Cluster II of fibre quality traits consisted of 3 crosses ( C2, C12, C15) showed highest average GOT(%) with highest tenacity (g/tex). Cross DS-5 x HD 123for SCY and bolls per plant, DS-5 x DLSA 9 for boll weight, DS-5 x CISA 65 for GOT % , CISA-2 x CISA 66 for lower micronaire value (fibre fineness) showed significant estimation of heterosis in desirable direction and could be further utilized in the future breeding programme for specific trait improvement.

Twenty three fungal endophytes isolated from desi cotton (Gossypium arboreum) were evaluated against two important pathogens of cotton Corynespora cassiicola and Fusarium solani, causal agents of leaf spot and seedling rot respectively. The internal transcribed spacer (ITS) region analysis was used for species-level identification of the fungal endophytes, wherein Curvularia (11) genus followed by Nigrospora (4) was found dominant whereas, Alternaria sp. (2) and Setosphaeria rostrata (2) were other prominent endophytes. Two isolates of Nigrospora sphaerica (CEL 5 and CEL 19) were highly efficient against C. cassiicola and inhibited mycelial growth up to 49.38% and 46.30%, respectively, whereas another isolate of N. oryzae (CEL 2) was effective against F. solani with inhibition of 43.06%. Besides, N. sphaerica (CEL 19) was found to influence the growth of test pathogens when tested for antibiosis. Through GC/ MS analysis of CEL 19 isolate, four major antimicrobial volatile organic compounds (VOCs), namely 1, 3‑diethyl benzene, 1, 4-diehtyl benzene, m-Ethylacetophenone, and p-cymene-7-ol were identified. The phylogeny tree constructed based on ITS sequences revealed two major branches and the first major branch consisted of most of the isolated fungal endophytes, whereas the second major branch consisted of only Coprinopsis cinerea and Puccinia chunjii. The 23 isolates divided into Ascomycota and Basidiomycota phyla were represented by four classes; Agaricomycetes, Eurotiomycetes, Sordariomycetes and Dothidiomycetes which were distributed into six orders. The majority of endophytes belonged to class Dothidiomycetes, followed by Sordariomycetes. There was no much difference observed between the endophytes and the reference taxa, even though it was a pathogen, indicating that pathogenicity of an organism is always not correlated with its gene sequence. Our findings suggest that N. sphaerica could be used as a potential biocontrol agent and its VOCs also have a role in suppressing the growth of plant pathogens.

Bemisia tabaci, a vector of cotton leaf curl virus disease, is among the most devastating pests causing huge economic losses due to reduced cotton yield and quality. The excessive use of chemical pesticides causes insecticide resistance. Entomopathogenic fungi (EPFs) have a role as mycoinsecticides. The combined use of these insecticides is a promising pest-control option to minimize adverse chemical effects. Thus, we have evaluated 10 EPFs under polyhouse conditions for their virulence against whitefly nymphs and their compatibility with chemical and botanical insecticides. The highest overall biological efficacy index was recorded with Ij-102, followed by Bb-4511, and Ij-089. An in vitro compatibility study was conducted to evaluate the effect of botanical and chemical pesticides on mycelial growth and spore production using the poisoned food technique. The effect of pesticides on the reduction of mycelial growth and conidial production ranged from -169 to 94.1% and -25.6 to 87.6%, respectively. However, Ij-089, Ij-102, Ma-1299, and Bb-4511 were found to be the most compatible with the chemical and botanicals evaluated. Comparatively, spiromesifen, diafenthiuron, buprofezin, pyriproxyfen, and flonicamid were more compatible with EPFs at half doses, as compared to the other chemical pesticides, namely imidacloprid, fipronil, profenophos, and triazophos. These results might provide the basis for future work and indicate that applications of EPFs showing the best virulence and compatibility have the maximum likelihood for the management of B. tabaci in the field in an integrated pest management system.

Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a serious pest of cotton that inflicts huge economic losses. Excessive use of chemical pesticides for its management causes environmental pollution and pesticide resistance. Six bioassay methods and ten entomopathogenic fungal strains (EPFs) were evaluated to find out the suitable bioassay method and the most virulent strain(s) for management of B. tabaci under laboratory and polyhouse conditions. The highest tenderness and survival period (> 30 days) of the leaves and increasing trend in nymphal mortality was recorded in a new modified polyhouse bioassay method (NMPBM). NMPBM was found to be effective, simpler, and less labor intensive for evaluating large numbers of EPF strains. Twelve newly isolated EPF strains were characterized based on their morphological and molecular characteristics. The highest whitefly nymphal mortality (at 107 conidia ml−1) was recorded by Beauveria bassiana (Bb)-4511 (95.1%), Bb-4565 (89.9%), and Metarhizium anisopliae-1299 (86.7%) at the seventh day post inoculation. However, the overall bioefficacy index was higher in Bb-4511 (78.1%), Cordyceps javanica (Cj)-102 (77.0%), and Cj-089 (75.4%) than other EPF strains. The lowest values of LC50 and LC90 were with Cj-089 and Bb-4511. The field deployment of effective formulation of these most virulent EPF strains might be helpful for managing B. tabaci populations and CLCuD incidence under insecticide resistance management programs.

The whitefly, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae), is becoming a serious problem on Bt cotton. It causes enormous crop loss through its direct feeding and as a vector of cotton leaf curl virus. Chemical-dependent management is harming the environment and increased insecticide resistance is often observed in the fields. Identification of most virulent strains of entomopathogenic fungi (EPF) is essential to serve as an important component of an IPM program for management of B. tabaci. Compared to B. tabaci adults, the nymphal stage is reported to be more susceptible to entomopathogens, and targeting nymphs also helps vector management. We evaluated the bioefficacy of EPF and chemical pesticides against nymphs of B. tabaci on Bt cotton under polyhouse and field conditions. The bioefficacy index (BI) was considered as a mechanism to select the most effective EPF strains for field evaluation. The highest nymphal mortality under polyhouse conditions was recorded for Metarhizium anisopliae NA-01299 (86.7%), Beauveria bassiana MT-4511 (85.1%), Cordyceps javanica IT-10498 (81.1%), IT-10499 (81%), and B. bassiana NA-0409 (78.2%) relative to other EPF strains, spiromesifen (69.6%), buprofezin (62.2%) and pyriproxyfen (52.7%) at 7-days-post-spray treatment (DAS). However, among all the EPF, the highest BI was recorded in C. javanica IT-10499 (77%), IT-10495 (75.4%), Fusarium verticillioides IT-10493 (74.6%), and B. bassiana MT-4511 (73.1%). The pooled data of two-year field trials (2017–18 & 2018–19) revealed that the highest nymphal mortality was recorded for MT-4511 (85%), IT-10499 (83.2%), and pyriproxyfen 10% EC (78.6%) at 7-DAS. The BI-based selection of EPF proved to be a useful predictor of field efficacy. A sequential spray of the selected EPF would be a vital approach for resilient and sustainable integrated management of the B. tabaci nymphal population under field conditions.

Microbial consortium of efficient strains for biological control helps in improving microbial efficacy, reliability, and consistency under diverse soil and environmental conditions. Different genera in consortial formulation occupy varied niches in the root zone, thereby restricting competition among them. In this review we have discussed critically the need of consortial application of bioagents, their role in rhizosphere colonization, and disease suppression. Potential of consortial application of bioagents against fungal, bacterial, and nematodes can be utilized to fullest extent by selecting most potential strains and not by arbitrary use of consortia. It was also discussed here that out of all the consortial formulation applied globally, very few show synergistic effect in consortia. A numerical analysis model to assess synergism is discussed in this chapter. Thus, it is essential to select strains of microbes very carefully to develop efficient consortia to suppress crop diseases.

Downy mildew caused by Bremia lactucae Regel on different members of Asteraceae has been reported from different parts of the world. In India, the pathogen is recorded for the first time on Sonchus asper and S. tenerrimus. This could be one of the option for biological control of Sonchus asper and S. tenerrimus.

Cotton leaf curl disease (CLCuD), caused by whitefly (Bemisiatabaci) transmitted single-stranded DNA viruses belonging to the Genus, Begomovirus (family, Geminiviridae) in association with satellite molecules; is responsible for major economic losses in cotton in three northwest (NW) Indian states Haryana, Punjab, and Rajasthan. Annual CLCuD incidences during 2012 to 2014 were estimated to be 37.5%, 63.6%, and 38.8% respectively. Cotton leaves were collected from symptomatic plants annually for three years and subjected to DNA isolation, followed by rolling circle amplification (RCA), cloning, and DNA sequencing of apparently full-length begomoviral genomes and associated betasatellites and alphasatellites. Among the thirteen CLCuD-begomoviral genomes recovered, eight were identified as Cotton leaf curl Multan virus-Rajasthan (CLCuMuV-Ra), one as -Pakistan (PK) and another as -Faisalabad (Fai), whereas, three were as Cotton leaf curl Kokhran virus-Burewala (CLCuKoV-Bu), indicating that CLCuMuV-Ra was the most prevalent begomovirus species. Five of the eight CLCuMuV-Ra sequences were found to be recombinants. The CLCuMuV-Ra- associated satellites consisted of Cotton leaf curl Multan betasatellite (CLCuMB), and Gossypium darwinii symptomless alphasatellite (GDarSLA), and Croton yellow vein mosaic alphasatellite (CrYVMoA). The second most abundant helper virus species, CLCuKoV-Bu, was associated with CLCuMB and GDarSLA.

Present study investigated the efficacy of 6 Trichoderma harzianum isolates against damping off and wilt diseases of brinjal and okra caused by Fusarium oxysporium (FO) and Pythium aphanidermatum (PA), respectively in order to get more effective isolates for disease management. Isolated pathogens from brinjal were named as Fob and Pab and from okra Foo and Pao for F. oxysporum and P. aphanidermatum, respectively. In vitro analysis revealed that T. harzianum isolates inhibited the radial growth of both pathogens and isolate Th-Sks was most effective with 78.44 and 74.16% growth inhibition of Fob and Pab, and 78.19 and 78.11% of Foo and Pao, respectively. Production of volatile and non-volatile metabolites by isolate Th-Sks was more aggressive in mycelial growth inhibition of all test pathogens than that of other isolates. Isolate Th-Sks had highest suppression efficacy i.e. 95.92 and 98.93% for Fob and Pab, 96.43 and 93.33% for Foo and Pao under glasshouse conditions, 96.18 and 95.73% for Fob and Pab, and 94.66 and 96.18% for Foo and Pao in the field conditions, respectively. Additionally, seed treatment of brinjal and okra with isolate Th-Sks gave a significant stimulatory effect on plant height (brinjal 52.9 cm; okra 110.5 cm) and increased fruit yield (brinjal 328.3 g; okra 294.6 g) in comparison to other isolates and control sets during field trials. Thus, it is concluded that isolate Th-Sks can be used as biocontrol agent for management of wilt and damping off diseases of okra and brinjal after multilocation trials.

The global population today is estimated to be about 6.8 billion and on its current growth trajectory, the population is expected to reach nearly 9 billion by 2042. Imbalanced diets lead to the death of millions of people each year and are an alarming problem in developing countries where micronutrient malnutrition is chronic and debilitating. Undernourishment, inadequate consumption of protein and energy as well as deficiencies in key micronutrients such as iodine, vitamin A and iron are key factors in the morbidity and mortality of children and adults in India. Though vegetables are recognized as the most important source of these micronutrients, yet the per capita vegetable consumption in India (86 g/day) is far below the FAO’s recommended (200 g/day). Recognizing the importance of nutrition, AVRDC-The World Vegetable Center has developed home garden packages as part of a project being implemented in Jharkhand and Punjab with grant from Sir Ratan Tata Trust (SRTT), to provide poor households with a balanced source of nutrition from year-round production of safe vegetables. The current paper highlights three home garden models - for Punjab, Jharkhand and Andhra Pradesh, developed and being validated in terms of their crop sequences, yield and nutritional output. Each home garden is of 6x6 m2 plot area with 5 main plots further divided into 13-15 sub-plots. Data analysis from August’08 till date for the evaluation trials conducted showed yields in the range of 185.70 to 345.21 kg for these models. The nutrient yield details showed that Andhra Pradesh, Punjab and Jharkhand models met more than 100% of β-carotene and vitamin C requirements for a 4-member family. However, the protein and iron requirements met by these models were low. These models have been promoted through more than 200 field demonstrations and distribution of healthy diet garden kits to further scale up home gardening amongst thousands of farmers.