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Structural genes of pollen are expressed in both sporophytic and gametophytic generations. This genetic overlap makes possible superior pollen genotype selection. Pollen selection is more effective than sporophytic selection since more pollen grains can be exposed to selection pressure at the haploid level. In this study, selection pressure was applied in the F1 generation at the pollen level for heat tolerance. The frequencies of heat‐tolerant plants were studied for seed yield in F2 and F3 generations and for seedling heat tolerance in F4 generations. The heat‐susceptible inbred line BTM4 was crossed to heat‐tolerant inbred line BTM6 of maize (Zea mays L.). In response to heat stress, we compared F2 plants produced by selfing of heat‐stressed pollen grains and without heat‐stressed pollen grains. The resulting F2 plants from heat‐stressed pollen grains showed significantly higher seed yield per plant (5.41 ± 0.31 g) than control F2 (2.90 ± 0.19 g) populations under stress. The selected and control F2 plants were also subjected to genotyping using simple sequence repeat (SSR) primers. We observed that the frequency of alleles from tolerant parents was higher in selected F2 populations, providing genetic evidence for positive effect of pollen selection. The heat tolerance of F4 generation progenies of the same cross suggested that the cyclic pollen selection for heat tolerance in F1, F2, and F3 generations has significantly improved the tolerance of progenies. The results from this study demonstrate that the feasibility of this approach seems to be promising for hastening the incorporation of desirable alleles in a short time.

Rainfall-runoff estimation for a catchment is of vital importance in most of the hydrologic analysis for water resources planning. This study envisages the rainfall-runoff modeling using MIKE 11 NAM model in Vinayakpur intercepted catchment in Chhattisgarh state. The model was calibrated using measured stream flow data for the period 2001 to 2004 and then validated from period 2005 to 2007. The calibration and validation procedures were carried out to provide a satisfactory estimation. The simulated runoff occurred maximum in August (1681.63 cumecs) and minimum in April (84.14 cumecs). The outputs of the calibrated model were used in water resources management model viz., MIKE basin as they normally work based on monthly flows with a large time horizon. The optimum values of nine NAM model parameters obtained during calibration procedure were used for simulation. The reliability of MIKE 11 NAM was evaluated based on Nash-Sutcliffe coefficient, correlation coefficient (r 2) and root mean square error (RMSE). The R 2 value of model calibration and validation were observed to be 0.79 and 0.75, respectively.

Accelerated crop growth strategy innovations are required as we reach saturation peaks regarding the productivity of major food crops. Speed breeding (SB) is one of the most promising technologies adopted for this purpose. SB hastens crop production by reducing plant growth and development, breeding time and swift generation advancement. Prolonged daily light exposure shortens the life cycle in some long-day or day-neutral plants leading to early seed harvest. This approach is best suited for controlled environment prebreeding/breeding activities and analysed for several crop species. SB can be integrated with different traditional and advanced genomicsassisted breeding technologies like marker-assisted selection (MAS), genomic selection (GS), pollen-based selection (PBS), overexpression/knock-down transgenics and genome editing to achieve more precise and faster results on translational genetic enhancement. This review will discuss the approaches and strategies adopted for the SB and its potential to integrate existing crop improvement technologies to attain more efficient outcomes on major food crops' varietal improvement.

Goat rearing is an important source of livelihood particularly for landless labourers and marginal farmers across the country. Evidence has shown that majority of goat farmers belonged to landless and marginal categories. Majority of goat farmers' annual income was between ` 10,001 to 20,000 and only 5% of farmers had an annual income of more than ` 50,000. Study also reveals that about 68% goats kept by farmers were from non-descript breed followed by Black Bengal (27%). Beside this nearly 14% of goat farmers were getting veterinary aid from government veterinary hospital while 86% of goat farmers were dependent on either private veterinarian or home remedies. Moreover, about 42% farmers were having hut type of houses for goat rearing. In the light of the results obtained it can be concluded that the production potential of goats could be enhanced with the introduction of superior technologies as well as improved practices which would help the farmers to contribute meaningfully to meet the needs of the family members and also improve the socioeconomic status of goat farmers.

An experiment was conducted to test the efficacy of irrigation methods and mulching in seed production of chickpea. Irrigation methods included drip with mulch (DM), drip without mulch (DNM) and check basin (CB) irrigation. Drip irrigation was scheduled at 1-day, 2-day and 7 days interval, while farmers’ practice of check basin irrigation at 7-day interval was considered as control. Plant parameters like height, horizontal spread, dry matter, root length and root spread, and number of pods were significantly influenced by irrigation levels and mulch. Seed yield of 17.7 and 16.8 q/ha was recorded for DM having 1-day and 2-day interval, respectively, which was about 82 and 73% higher over the control. The harvest index increased with increasing irrigation interval and was highest (57.4) under treatments with longer irrigation interval (DM7, DNM7 and CB7). Drip irrigation at 1-day and 2-day interval recorded the water productivities of 0.54 and 0.52 kg/m3, respectively as against 0.30 kg/m3 recorded in farmers practice. Polythene mulch with drip irrigation at 2-day irrigation interval is recommended for improving the yields and water productivity of chickpea cultivated under eastern plateau and hill region of India.

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