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Tomato is a widely cultivated crop significant for its economic and nutritional benefits. The South American tomato pinworm, Tuta absoluta, originated in Peru South America and has invaded many nations, causing up to 100% yield loss in tomatoes. The pest was classified as a quarantine pest by the European Plant Protection Organization, before invading the Spain region. Later, this quarantine pest also invaded other regions of Europe, Africa and Asian countries. Invasive insect pests cause global economic losses of 70 billion dollars annually. Among the several management measures suggested against pests, insecticides are the primary method in practice among growers due to significant results, easier operations, and other crucial advantages. Anyhow, repeated application of insecticides has caused the pest to evolve resistance against most of the insecticides in vogue, resulting in a chain of events like management failures, using increased doses of insecticides, intensified chemical residues in the food chain, and irreparable environmental contamination. Major insecticides globally used to control T. absoluta belong to organophosphates, synthetic pyrethroids, neonicotinoids, diamides, avermectins, spinosyns, and oxadizines. Understanding the baseline susceptibility of pests to insecticides helps for better pest management options and is the same for T. absoluta populations to insecticides. The current review paper discusses the T. absoluta distribution, biology, spread, host range, baseline insecticide susceptibility, global insecticide resistance status, and possible management inputs based on our understanding of insecticide susceptibility. The pest can be managed with integrated insecticide resistance management including molecular approaches.

Terminal heat stress has become one of the major threats due to global climate change which is significantly affecting the production and productivity of wheat crop. Therefore, it is necessary to identify key traits and genotypes to breed heat-tolerant wheat. The present study was undertaken with the objective of comparing the effects of heat stress (HSE) and extended heat stress (EHSE) on phenological-physio-biochemical traits of contrasting heat-tolerant and heat-susceptible genotypes during the reproductive phase. Phenological traits exhibited significant reduction under EHSE compared to HSE. Heat-tolerant genotypes maintained balanced phenological-physio-biochemical traits, while heat-sensitive genotypes showed significant reductions under both stress regimes. Among phenological traits, DM (R2 = 0.52) and BY (R2 = 0.44) have shown a positive effect on seed yield, indicating that biomass and crop duration contributed to the yield advantage under stress. During the grain filling stage, both the normalized difference vegetation index (NDVI) and chlorophyll (Chl) exhibited consistently positive impacts on grain yield under both HSE and EHSE conditions. This could be attributed to the enhanced photosynthesis resulting from delayed senescence and improved assimilate remobilization under terminal heat stress. The biochemical activity of superoxide dismutase (SOD), peroxidase (POX), and ascorbate peroxidase (APX) was induced in tolerant genotypes under HSE. The correlation of canopy temperature with phenological-physio-biochemical traits remained static under HSE and EHSE, suggesting CT as the best selection parameter for heat tolerance. The traits showing a positive association with yield and that are less affected under stress could be used for selecting tolerant genotypes under stress environments. These tolerant genotypes can be used to develop mapping populations to decipher the genes conferring tolerance as well as to study the molecular basis of tolerance.

Climate change has resulted in extreme temperature and drought around the globe, which poses serious threat to food security. Both heat and drought stress affects the production and productivity of wheat crop. The present study was undertaken to evaluate 34 landraces and elite cultivars of Triticum spp. for phenological and yield-related traits under optimum, heat, and combined heat–drought stress environments during 2020–2021 and 2021–2022. The pooled analysis of variance showed significant genotype × environment interaction, suggesting an influence of stress on trait expression. The trait performance of genotypes exhibited significant reduction under combined heat–drought stress as compared to optimum and heat stress environments. The maximum seed yield penalty was observed under combined heat–drought stress environment as compared to heat stress alone. Regression analysis indicated significant contribution of number of grains per spike towards stress tolerance. Based on Stress Tolerance Index (STI), genotypes Local-17, PDW 274, HI-8802, and HI-8713 were identified to be tolerant to both heat and combined heat and drought stress at Banda, whereas genotypes DBW 187, HI-8777, Raj 4120, and PDW 274 were tolerant at Jhansi location. The genotype PDW 274 showed stress tolerance under all treatments at both the locations. The genotypes PDW 233 and PDW 291 showed highest stress susceptibility index (SSI) across the environments. The number of grains per spike and test kernel weight were positively associated with seed yield across the environments and locations. The selected genotypes Local-17, HI 8802, and PDW 274 were identified to be the potential sources of heat and combined heat–drought tolerance, which may be utilized in hybridization to develop tolerant wheat genotypes and also for mapping of underlying genes/quantitative trait loci (QTLs).

Late embryogenesis abundant (LEA) proteins are identified in many crops for their response and role in adaptation to various abiotic stresses, such as drought, salinity, and temperature. The LEA genes have been studied systematically in several crops but not in Vigna crops. In this study, we reported the first comprehensive analysis of the LEA gene family in three legume species, namely, mung bean (Vigna radiata), adzuki bean (Vigna angularis), and cowpea (Vigna unguiculata), and the cross-species expression of VrLEA genes in a wild tetraploid species, Vigna glabrescens. A total of 201 LEA genes from three Vigna crops were identified harboring the LEA conserved motif. Among these 55, 64, and 82 LEA genes were identified in mung bean, adzuki bean, and cowpea genomes, respectively. These LEA genes were grouped into eight different classes. Our analysis revealed that the cowpea genome comprised all eight classes of LEA genes, whereas the LEA-6 class was absent in the mung bean genome. Similarly, LEA-5 and LEA-6 were absent in the adzuki bean genome. The analysis of LEA genes provides an insight into their structural and functional diversity in the Vigna genome. The genes, such as VrLEA-2, VrLEA-40, VrLEA-47, and VrLEA-55, were significantly upregulated in the heat-tolerant genotype under stress conditions indicating the basis of heat tolerance. The successful amplification and expression of VrLEA genes in V. glabrescens indicated the utility of the developed markers in mung bean improvement. The results of this study increase our understanding of LEA genes and provide robust candidate genes for future functional investigations and a basis for improving heat stress tolerance in Vigna crops.

Fifty Italian millet genetic resources were studied to assess the magnitude of genetic diversity for 12 quantitative traits using Mahalanobis D2 Statistic. Based on Tocher’s method, the entire genetic resources were partitioned into nine distinct nonoverlapping clusters suggesting availabilty of substantial genetic diversity. Cluster I was the largest comprising of large number of accessions (36) followed by cluster II with (7) accessions and the remaining were mono genotypic clusters III, IV, V,VI,VII, VIII and IX containing only single accession each indicating high degree of heterogeneity among the genotypes. Clusters II and IX showed maximum inter-cluster distance between them implying these genetic resources with high degree of genetic diversity may be utilized in inter-varietal hybridization programme. The trait, culm branches followed by 1000 grain weight contributed maximum towards total divergence indicating feasibility of improvement through those characters.

The knowledge of genetic variability in a given crop species for characters under improvement is important in any plant breeding programme. Genetic parameters for yield and its correspondent characters in rice were estimated from a trial conducted at Rice Research Centre, Agricultural Research Institute, PJTSAU, Hyderabad during Kharif, 2017. In the present study, four Cytoplasmic Male Sterility lines, eight male lines and thirty-two hybrids and four checks were evaluated. The analysis of variance showed highly significant differences among the genotypes for all the characters, indicated the presence of enormous amount of genetic variability. High phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) was observed for number of grains per panicle (26.55, 23.16) and grain yield per plant (21.67, 21.24) indicating that these characters could use as selection for crop improvement. High heritability coupled with high genetic gain as percentage of mean was observed for number of grains per panicle (70.26, 41.61) and 1000 grain weight (61.9, 29.52) which showed presence of additive gene action and thus the chances of fixing by selection will be more to improve such traits through pure line selection in the evaluated genotypes.

The present investigation was conducted with 104 accessions of mungbean during summer 2012-13. Morphological characterization of accessions indicated high level of variation among gene pool. High GCV, PCV, heritability coupled with high genetic gain of agro-morphological traits viz., number of primary branches per plant, number of secondary branches per plant, peduncle length, leaf pubescence density, stem pubescence density, petiole pubescence density, number of clusters per plant and harvest index, indicating that selection will be effective for these traits. The genotypes were grouped in to various groups based on qualitative and quantitative traits, indicating the diversity of genotypes. This study may give better chance to select the genotypes with different weight for mungbean improvement

Thirty eight rice genotypes were evaluated at Field Experimentation Centre, Department of Genetics and Plant Breeding,Allahabad School of Agriculture, SHIATS, Allahabad in Randomized block design with three replications during kharif-2009.The experiment was conducted to study the 12 quantitative traits to examine the nature and magnitude of variability, heritabilityand genetic advance. The mean sum of square for all the 12 characters were significant indicating the presence of substantialamount of variability. High estimates of heritability coupled with high genetic advance as per cent of mean was observed forharvest index (99.66, 78.57) followed by number of spikelets per panicle (99.66, 69.05), number of panicles per hill (99.61,53.56) and number of tillers per hill (99.81, 51.68). High estimates of heritability coupled with moderate genetic advance as percent of mean was observed for flag leaf width (65.17, 20.33) followed by days to 50% flowering (99.30, 22.54), panicle length(97.30, 31.32) and biological yield per hill (99.97, 34.59).

Thirty six greengram genotypes were evaluated during kharif 2012 in three environments for analysis of quantitative traits. Association analysis showed significant positive relationship between seed yield and some of the agro-morphological traits viz., days to 50% flowering, primary branches per plant, secondary branches per plant, clusters per plant, pods per cluster, pod length, seeds per pod, pod mass, pod wall mass, seed mass, selling percentage, seed index and harvest index. Hence these traits may be used as selection criteria for yield improvement. Based on principle component analysis, pod length, seeds per pod, pod mass, seed mass, pod wall mass, selling percentage, seed index and harvest index were found important and can be added in breeding program. Sona selection had moderate to more diversity with all the genotypes due to their solitary nature, and can be used in breeding program for greengram improvement. Besides this, representative genotypes from each cluster may be selected for future hybridization to get good segregants in segregating generations.

Principal component analysis (PCA) with 36,621 polymorphic genome-anchored single nucleotide polymorphisms (SNPs) identified collectively for Capsicum annuum and Capsicum baccatum was used to show the distribution of these 2 important incompatible cultivated pepper species. Estimated mean nucleotide diversity (π) and Tajima’s D across various chromosomes revealed biased distribution toward negative values on all chromosomes (except for chromosome 4) in cultivated C. baccatum, indicating a population bottleneck during domestication of C. baccatum. In contrast, C. annuum chromosomes showed positive π and Tajima’s D on all chromosomes except chromosome 8, which may be because of domestication at multiple sites contributing to wider genetic diversity. For C. baccatum, 13,129 SNPs were available, with minor allele frequency (MAF) ≥0.05; PCA of the SNPs revealed 283 C. baccatum accessions grouped into 3 distinct clusters, for strong population structure. The fixation index (FST) between domesticated C. annuum and C. baccatum was 0.78, which indicates genome-wide divergence. We conducted extensive linkage disequilibrium (LD) analysis of C. baccatum var. pendulum cultivars on all adjacent SNP pairs within a chromosome to identify regions of high and low LD interspersed with a genome-wide average LD block size of 99.1 kb. We characterized 1742 haplotypes containing 4420 SNPs (range 9–2 SNPs per haplotype). Genome-wide association study of peduncle length, a trait that differentiates wild and domesticated C. baccatum types, revealed 36 genome-wide SNPs significantly associated. Population structure, identity by state (IBS) and LD patterns across the genome will be of potential use for future genome-wide association study of economically important traits in C. baccatum peppers.