ABSTRACT
The present investigation was carried out with 78 diverse horse gram [Macrotyloma uniflorum (L.) Verdc] genotypes along with 4 checks during the late Kharif season. Data was recorded on days to 50 percent flowering, days to maturity, plant height, number of branches per plant, pod length, number of seeds per pod, number of pods per plant, pod weight (g), seed yield per plant (g), and 100-seed weight (g). Analysis of variance revealed significant differences among all the genotypes for all the characters studied. A wide range of variations had been observed for all the characters except for the number of seeds per pod. The highest coefficient of variation was observed in the number of pods per plant followed by 100 seed weight and seed yield per plant. The phenotypic coefficients of variation (PCV) were higher than the genotypic coefficient of variation (GCV) for all the traits but the differences were narrow. The highest magnitude of PCV and GCV were recorded for seed yield per plant (g) followed by pod weight (g) indicating a wide range of variation which provides a chance for yield improvement. High heritability coupled with high genetic advance was observed for plant height, number of branches per plant, number of pods per plant, pod weight, seed yield per plant, and 100 seed weight indicating additive gene action and the abundant scope for improvement in these traits through simple selection. This study provides information about the performance of the genotypes and identifies some prominent genotypes. Thirty-three genotypes recorded significantly higher seed yield per plant as compared to the best-performing check. These genotypes were IC 426292, IC 470167, IC 426471, IC 470229, IC 470206, IC 470262, IC 426464, IC 107247, IC 108076, IC 426550, IC 426540, IC 108078, IC 426537, IC 470166, IC 467865, CRHG-1, IC 426539, IC 426478, IC 426524, IC 426549, IC 426522, IC 470170, IC 261278, IC 470188, IC 426535, IC 107222, IC 226533, IC 426574, IC 426523, IC 526965, IC 426571, IC 426517 and IC 426538. These genotypes may be further used for parental selection in breeding programs for the improvement of yield and its attributes in horse gram.
ABSTRACT
Black gram (Vigna mungo (L.) Hepper) var. IC-282009 - a highly CO2 responsive genotype for biomass and seed yield was grown in Open top chambers (OTCs) under three levels of CO2 i.e. ambient (390 ppm) and two elevated levels 550ppm and 700ppm to assess photosynthetic acclimation to elevated CO2. Net photosynthetic rate (PN), change in leaf soluble protein profile and leaf carbohydrate constituents such as total soluble sugars, reducing sugars and starch content in leaves was quantified at all three CO2 concentrations. Photosynthetic rate was enhanced by 78% and 30% at flowering stage with 550ppm and 700ppm CO2 as compared with ambient control. It was also observed a higher accumulation of starch, total soluble sugars and reducing sugars in leaves at elevated CO2 levels. However, the leaf protein content recorded a decrease and altered the profile of ploy peptides with enhanced CO2 levels. At elevated CO2 concentrations significant differences were observed in ploy peptide profile at vegetative and flowering stages, the intensity of 260 kDa poly peptide increased at vegetative stage, whereas 72 kDa polypeptide increased at flowering stage, while 52 kDa poly peptide decreased at both stages. Enhanced CO2 concentrations improved the PN though certain polypeptides of leaf protein are down regulated and necessitate further experimentation to confirm their involvement in responsiveness of the selected black gram genotype.