Intercomparison of crop establishment methods for improving yield and profitability in the rice-wheat system of Eastern India.

Conventionally managed rice-wheat systems of the eastern Indo-Gangetic Plains (E-IGP) that rely on soil puddling for rice and intensive tillage for wheat are low-yielding and resource-inefficient, leading to low profitability. While a host of alternative tillage and crop establishment (TCE) methods have been advocated as solutions for sustainably enhancing productivity and profitability, few systematic comparisons of these methods are reported. To address this gap, a three-year field study was conducted in Bihar, India with the goal of identifying TCE methods for rice-wheat systems that are high yielding, less resource-intensive, and more profitable. The following systems were evaluated: 1) puddled transplanted rice (PTR) followed by (fb) conventional tillage wheat (CTW) or zero-tillage wheat (ZTW); 2) machine transplanted rice in non-puddled soil (MTR) fb ZTW; 3) the system of rice intensification (SRI) fb system of wheat intensification (SWI); and 4) dry-seeded rice (DSR) fb ZTW. Rice cultivar duration (short versus medium-duration) was incorporated as a subplot treatment in all systems. Rice yields were similar with all methods, except DSR yield was 11 % lower and MTR yield was 7% higher than PTR in the third year. Cost of production was US$ 149 and 77 ha-1 lower in DSR and MTR, respectively, and US$ 84 ha-1 higher in SRI than PTR. The gross margin and benefit-cost (B:C) ratio was highest in MTR followed by DSR and lowest in SRI. In wheat, ZT resulted in a higher yield than CTW, especially when ZTW was cultivated after non-puddled rice (e.g., DSR or MTR). ZTW reduced production costs by US$ 69 ha-1, whereas SWI increased it by US$ 139 ha-1 relative to CTW. The higher yield and lower cost of production resulted in a higher gross margin (US$ 82-355 ha-1 and US$ 129-409 ha-1 higher than CTW and SWI, respectively) and a higher B:C ratio in ZTW treatments than CTW and SWI. At the system level, MTR or DSR followed by ZTW had both superior crop yields and consistently higher gross margins (US $133 to 382 ha-1) than other practices. On the other hand, the SRI fb SWI system had no yield advantage and poorer economic performance than conventional practices. In all systems, the inclusion of a medium-duration rice hybrid resulted in higher rice and system yields. These results suggest that significant gains in profitability are possible with emerging TCE practices in rice-wheat systems, but alternatives such as the SRI and SWI will likely erode farmer incomes.

Ethyl methane sulphonate induced genetic variability and heritability in macrosperma and microsperma lentils.

Dry and healthy seeds of two lentil cultivars, LH90-54 (macrosperma) and LH89-48 (microsperma) were treated with three doses of ethyl methane sulphonate (0.1, 0.2 and 0.4 %). In both the cultivars, all the M, plants with sufficient seed from each treatment and control were taken to raise independent M2 plant progenies. Wider range of means in both positive and negative directions along with overall positive shift in mean for all the polygenic traits, except pod-initiation height and 100-seed weight, were observed in different treatments in M2 generation. In both the cultivars, medium dose induced highest amount of variation. The estimates of variance, GCV and PCV for different polygenic traits increased significantly over control values in all the treatments of both the cultivars. Higher estimates of heritability and genetic advance in M2 population indicated tremendous scope for the improvement of seed yield and its component traits through selection in the mutagenized material.

Variability in physicochemical and nutritional quality traits of parents, F2 and F3 generations of lentil crosses.

Ten physicochemical and nutritional quality traits (100-seed weight, seed volume, seed density, bulk density, hydration capacity, hydration index, swelling capacity, protein, tryptophan and energy value) were examined in the seed samples of parents, F2 and F3 generations of three microsperma x microsperma and two microsperma x macrosperma crosses of lentils. Significant variation for different traits was observed among the genotypes in both the groups and also among both types of crosses in F2 and F3 generations. Ranges, means and coefficients of variation (CV %) for various traits among parents, F2 and F3 generations of different crosses, along with the deviations between F2 and F3 generation means for various traits in different crosses are discussed. Also suggested is a breeding strategy for evolving lentil varieties with improved seed yield and nutritional quality parameters.

Nutritional parameters and yield evaluation of newly developed genotypes of lentil (Lens culinaris Medik.).

Among the commonly consumed food legumes, lentils occupy an important place in human nutrition in the Indian subcontinent. Twenty-one lentil genotypes were evaluated for such nutrition related parameters as moisture, protein, crude fiber, fat, ash (total mineral matter), carbohydrates, total energy and metabolizable energy. These genotypes were also analyzed for 100-seed weight and seed yield/plant. Protein content ranged between 22.1 and 27.4% with significant differences among genotypes. Considerable variations were observed among the genotypes for calcium, phosphorus, iron and tannin contents. Large variations existed in yield and 100-seed weight of these genotypes. Seed yield/plant was not significantly correlated with any of the principal seed constituents analyzed in the present study. The genotypes, LH 97 and LH 37 were found to be better and hence could be explored for further development and selection of desirable characteristics.

Early generation yield testing versus visual selection in chickpea (Cicer arietinum L.).

Four F3 populations of chickpea (Cicer arietinum L.) were simultaneously evaluated for yield in an F3 yield trial and in single plant progeny rows. Ten high yielding, 10 low yielding and 10 randomly sampled lines, along with 10 lines visually selected for yield from the progeny rows, were retained for further evaluation. The lines from each of the four selection groups in each population were bulked and evaluated in a replicated yield trial at three locations and four environments. The bulk of visually selected lines was not superior in yield to the bulk of randomly sampled lines at all locations. The present results indicate that an early generation yield testing selection procedure is more efficient than visual selection for yield improvements in chickpea.