RESUMEN
In current study 113 diverse genotypes of chickpea has been evaluated during rabi 2019-20 and 2020-21 under timely sown (TS), late sown (LS) and very late sown (VLS) cropping environment in augmented block design at research farm of ICAR-IIPR, Kanpur for genetic characterization to access the presence of variability among the major grain yield attributing traits under changing cropping conditions. Variation due to block were insignificant and error variance was significant for all three different trials (ie., TS, LS and VLS) conducted during rabi 2019-20 and 2020-21(Table 5) In the present study highest genotypic and phenotypic coefficient of variation was observed for UFP, SYP (g), PB, Y (kg/ha), PY (g), HI (%), BMP (g), HSW (g) and FP (Table 5) While the traits viz., DFI, DFF, DPI, DFP, DMI, DM and PHT (cm), BY (g) and NSP exhibited the moderate to low range of GVC and PCV value under TS, LS and VLS cropping conditions During rabi 2019-20 and 2020-21. Highest value of heritability (%) >60% have been observe for the traits DFI, DFF, DMI, DM, PB, Y (kg/ha), HSW (g), SYP (g), BMP (g) and FP in all three different cropping environments (Table 6 in the current study correlation coefficient analysis have been estimated for the Correlation values (Table 6) for all three different trials viz Timely sown (TS), Late sown (LS) and Very Late sown (VLS) conducted in Rabi 2019-20 and 2020-2021. The Pearson correlation coefficients of pooled data were calculated for Eighteen morphological traits The major yield contributing traits such as DFF, PHT (cm), PB, SYP (g), PY (g), Y (g), HSW (g), BY (g) and HI (%) have significantly correlated with all the traits except UFP and NSP (Table 6) The PY (g) exhibited strong positive correlation with Y (Kg/ha) (0.857** and 0.964**); HSW (g) (0.544* and 0.412*); BY (g) (517* and 0.856**); SYP (g) (0.628**and 0.506*); BMP (g) (0.553* and 0.494*); HI (%) (0.459* and 0.706**). Similarly, another chief yield contributing traits like SPY (g) is also positively correlated BMP (g) (0.536* and 0.682**); HI (%) (0.678** and 0.779**); FP (0.774** and 0.964**) and NSP (0.456* and 0.503*) except UFP (Table 7 maximum percentage of variance for all 113 diverse chickpea genotypes has been recorded for PC1(26.83, 26.63 & 31.46 in 2019-20; 29.87, 35.15 & 30.2 in 2020-21) and PC2 (24.19, 22.81 & 12.66 in 2019-20; 18.96, 15.43 & 17.4 in 2020-21) for all three separate trials i.e., TS, LS and VLS (Table 7).
RESUMEN
Increased temperature is a major yield declining factor in wheat production. Current study was intended to evaluate the impact of increased temperature on the pre and post reproductive major yield attributing biometrical traits through the use of stress tolerance indices and trait reduction ratio (%) of all the traits studied. A set of 27 genotypes including 2 check entries viz., Shriram 303 and HD 2967 was evaluated in two separate trials, timely sown (non-stress) and late sown (heat stress) conditions in RBD design with three replications during rabi 2020-21 at the agriculture research farm of Rama university, Kanpur. Significant dropping in major yield attributing traits have Such as grain yield/plant, grain yield/spike and tillers/plant exhibited 54.41%, 39.31 % and 34.22% reduction, respectively thought the estimation of trait reduction ration (%) specially for the trials conducted under the late sown (heat stress) condition as compared to the normal sown trial. Five stress tolerance indices viz., susceptibility index (HSI), mean productivity (MP), tolerance (TOL), heat tolerance index (STI) and trait stability index (TSI) have been estimated to find out the heat stress tolerance and susceptible genotypes for grain yield under high temperature stress conditions.Correlation estimates of different heat stress tolerance indices with grain yield in non-stress condition (timely sown) exhibited significant positive association with MP (0.766**), HTI (0.622**), TSI (0.414*), and TOL (0.284). Though, under heat stress condition (late sown), grain yield displayed a significant positive correlation with HTI (0.713**), MP (0.707**), TOL (0.517**), TSI (0.656**) and negative correlation with HSI (-0.608**). Through the correlation analysis estimates, four heat stress indices viz. HSI (heat susceptibility index), MP (mean productivity), STI (stress tolerance index) and TSI (trait stability index) have been used in assorting the heat tolerant wheat genotypes. Current estimates directed that 14 genotypes (PBW 152, HUW-206, WL-2, WL-8, WL-13, DBW-71, DBW-39, WH-1105, HUW-318, PBW-154, ALWL-5, WL-14, PBW-502 and Shriram 303) were heat tolerant genotypes while 8 genotypes (Jamuni, F 2004, Allahabad Local, Black, U. P Local, YOUDA, U. P B2425 and HD 2967) have been observed high temperature susceptible. While WH-1105 and PBW-154 have been observed high yielding genotypes under heat stress environment. Therefore, genotypes WH-1105 and PBW-154 were acknowledged as a suitable genotype for late sown trial. Further, these two genotypes could be utilize in breeding programme to develope heat tolerant varieties of wheat.