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Ascochyta blight (AB), caused by a fungal pathogen Ascochyta rabiei is a serious threat to chickpea cultivation. It becomes, thus, imperative to evaluate the existing germplasm against this disease as a foundational step toward crop enhancement. We prepared a potent inoculum of the prevalent local races of the pathogen and assessed the disease resistance of eighty chickpea genotypes containing approved varieties, advance lines etc., against AB. Out of total eighty genotypes, six, fifty six and eleven genotypes correspondingly, were found resistant, tolerant and susceptible. Using the tool of association mapping, we were able to detect 43 marker trait associations (MTAs) for disease severity while 36 MTAs for disease score and many genes related to stress tolerance in both growing seasons. The six resistant genotypes identified in our germplasm can be an excellent source for breeding AB resistant chickpea cultivars. In addition, the significant MTAs linked with AB may assist in the molecular breeding program to develop high yielding disease resistant cultivars of chickpea. [ABSTRACT FROM AUTHOR]

The energy crisis is giving rise to long term social and economic issues as they both are closely related. The production of biofuel from plant-based biomass is becoming an attractive alternative to non-renewable energy sources. Sorghum is a model bioenergy crop owing to its high biomass yield and low input requirements. In the present study, 142 accessions of Sorghum bicolor were evaluated for biomass (plant height (cm), stem thickness (mm), no. of leaves/plant, leaf area (cm²), internodal length (cm), green fodder yield (g)) and biofuel (moisture contents (%), protein contents (%), acid detergent fiber (ADF), neutral detergent fiber (NDF), ash contents (%), crude fat (%) and hemicellulose content (%)) related traits, selected accessions were crossed in line × tester mating design, seven lines and five testers were selected and resultant F1 progeny along with their parents were evaluated and data were recorded to estimate genetic variability, additive and dominance variance, combing ability effects, and gene action among the traits. Highly significant differences were found among all the accessions, parents, parents vs crosses, crosses, lines and testers. Line × tester was also found significant for all the biomass traits and biofuel related traits except moisture content and ash content. Genetic variability indicated that this material can be used for the development of improved genotypes for biomass and biofuel related traits. Results of general combining ability estimates indicated that lines L1, tester T5 were the best general combiners for biomass traits and L6, L7, testers T1, T2 for biofuel related traits. Whereas specific combining ability estimates indicated that crosses L1 × T3, L1 × T5, L2 × T2, L3 × T5, L7 × T3 were the best specific combiners for biomass and L2 × T2, L4 × T5, L5 × T1 for biofuel. Partial dominance was observed for most of the traits. Based on association studies, plant height, green fodder yield, neutral detergent fiber, and hemicellulose might be used as selection criteria for improved biomass and biofuel related traits in sorghum breeding. [ABSTRACT FROM AUTHOR]

Direct shoot regeneration (adventitious regeneration) with no intervening callus phase is preferred over indirect regeneration in tissue culture of plants owing to no/ low genetic variations. We report the development of a reproducible in vitro adventitious regeneration protocol for citrus cultivars; Kinnow, sweet lime, lemon and rough lemon. Inter nodal stem segments isolated from in vitro- grown citrus seedlings were cultured on MS medium fortified with varying BAP, NAA and kinetin concentrations. Data for days to shoot initiation, frequency of shoot induction and rooting frequency were recorded. Sweet lime exhibited the earliest shoot induction while; Kinnow explants showed delayed regeneration response. The MS + BAP 1mg/l proved the best medium for early shoot induction in all citrus cultivars. All four cultivars exhibited varied responses to different shoot induction media. Kinnow was the least responsive and sweet lime showed the highest regeneration response with 29.8% and 55.6% mean shoot induction frequencies, respectively. Single shoots were transferred to MS- based rooting medium fortified with 1, 1.5, 2 and 2.5 mg/l of NAA. Rooting frequency ranged from 7.0 to 73% in Kinnow and sweet lime, respectively. The best rooting medium for shoots of all citrus cultivars was MS+ 2mg/l NAA. Well-rooted plantlets were shifted to the potting mixture with 85% successful adaptation. LSD test at 5% significance level was used to calculate the statistical significance of recorded data. This optimized reproducible and efficient adventitious regeneration system has applications in citrus micropropagation, genetic transformation, protoplast fusion and germplasm conservation. [ABSTRACT FROM AUTHOR]

Genetic gains of crops could be improved by pyramiding physiological, agronomic and stress tolerant traits in single genotypes. Comprehensive foreground and background phenotypic information is a prerequisite for any molecular and strategic breeding program. A population of 465 local spring wheat (Triticum aestivum L.) genotypes was characterized using various agromorphological and yield traits for two cropping seasons. Average values ranged from 92%-112%, 80%-240%, 48%-57% and 34%-42% for plant height, harvest index, grain per spike and 1000 grain weight, respectively. In both years, there was a strong correlation of yield per plant with plant height, harvest index, 1000 grain weight and grain per spike. Factor1 and factor2 of principal component analysis (PCA) explained the maximum variability ranges from 21%-19% for the first year and 19%-16% for the second year. Plant height and yield per plant showed a significantly positive correlation with genotypes during both cropping seasons. Cluster analysis divided genotypes into three distinct groups indicating the existence of considerable variation. The extent of variation and correlation among genotypes is required for effective utilization and conservation of the genetic resource. Based on PCA, genotypes with highest score and desirable characters can be selected for further breeding programs. [ABSTRACT FROM AUTHOR]

Zinc (Zn) is needed for plants growth and human's balanced diet. The non-availability or less mobilization of Zn affects crop yield and nutritional quality and when such produce is consumed, it causes malnutrition in the consumers. Biofortification of staple cereals and vegetables like tomato (Solanum lycopersicum L.) is one of the strategies to fight such type of hidden hunger, particularly to crumble Zn deficiency. This needs the understanding of the molecular mechanism of Zn assimilation in plants. ZIP genes have not been annotated and characterised earlier. Therefore, the genes of ZIP family were identified from genome database by homology search. After carrying out the phylogenetic analysis, the 10 diverse genes of tomato ZIP family were selected for the transcript profiling in two selected genotypes; one with the highest Zn assimilation (LA-2662) and the other with the lowest one (NTH-242) was done. The RT-PCR results showed that in genotype LA-2662, genes SLZIPL, SLZIP3 SLZIP5L and SLZIP5 were upregulated in roots and leaf tissues, while their transcript level was the lowest in genotype NTH- 242. In addition, the genes; SLZIPL, SLZIP3, LeIRT1 and LeIRT2 were upregulated under Zn deficient environment and downregulated in high Zn environment. The better performance of LA-2662 for Zn assimilation might be linked to the upregulation of SLZIPL and SLZIP3 genes. It showed that the attenuation of these candidate genes might improve the capability of tomato for the development of Zn fortified tomato genotypes. It further showed that tomato can be bred for biofortification of various nutritional elements to fight hidden hunger. [ABSTRACT FROM AUTHOR]

The present in vitro study was conducted to screen 60 genotypes of Brassica napus L. at seedling stage in Polyethylene glycol (PEG-6000) mediated drought stress. The trial was laid out in a completely randomized design with factorial structured treatments having three replications. Three levels of stress, i.e. 0 (control), -0.35 and -0.60 MPa were developed by dissolving 0, 5, 10g of PEG-6000/100 ml de-ionized water respectively. After 14 days data was recorded for shoot length (cm), root length (cm), fresh root and shoot weight (g) and dry root and shoot weight (g). The seedlings growth decreased with increasing concentration of PEG-6000 due to an increase in water stress. The genotypes which showed better performance in both treatments were selected as drought tolerant genotypes. Eight genotypes that are Faisal sarson, Dunkled, RBN, Punjab sarson, Rainbow, Chakwal sarson, Shiralee and Legand were selected as drought tolerant genotypes. These drought tolerant genotypes will be helpful for genetic improvement in Brassica napus L. crop in the future breeding programmes. The current research will be helpful for the selection of tolerant genotypes in water deficit conditions at early seedling stage. [ABSTRACT FROM AUTHOR]