Mustard (Brassica napus) belongs to the Brassiacaceae family and is the major edible oil producing crop of Bangladesh. The country spent a huge amount of foreign currency to import edible oil, which could be minimized through enhancing and improving the existing germplasms. To do this, the genetic variability and diversity of the existing germplasm should be evaluated. Thirty-five genotypes of mustard were evaluated based on randomized complete block design with three replications. The genotypes were found significantly variable for most of the characters. Comparatively phenotypic variances were higher than the genotypic variances for most of the characters studied. The high GCV value was observed for number of seed yield per plant. Seed yield per plant exhibited the highest value of heritability followed by number of siliquae per plant while plant height exhibited the lowest value of heritability. The significant positive correlation with seed yield per plant were found in number of primary branches, siliquae length, number of seed per plant, number of seed per siliquae and thousand seed weight. Path coefficient analysis revealed that days to maturity, plant height, number of primary branch, siliquae length, number of siliqua per plant, number of seed per siliqua, and thousand seed weight, had direct positive effect on yield per plant. Whereas, days to 50% flowering, length of main raceme and number of secondary branch had direct negative effect on yield per plant. The genotypes were classified in four clusters. The genotypes of cluster IV showed better mean performance while cluster III showed lower mean performance for important component traits including yield per plant. Considering distance and agronomic performance genotypes G23, G5, G22 and G24 might be recommended for future hybridization program.

No abstract

Lucerne (Medicago sativa L.) is a cross-pollinated crop and requires entomophilous pollination for tripping of flowers and subsequent pod and seed set. To discover the best pollinators for lucerne seed production, a two-year field trial was carried out at the research farm of MNS University of Agriculture, Multan, Pakistan. Abundance and diversity of insect pollinators along with the foraging behavior were recorded in terms of tripping efficiency, stay time, visitation rate and pollen harvest. The single-visit efficiency of abundant insect pollinators was also evaluated in terms of number of seeds and seed weight per raceme along with germination percentage. Ten most abundant floral visitors (five solitary bee species, three honeybee species and two syrphid fly species) were tested for their pollination efficiency. Honeybees were most abundant in both the years followed by the solitary bees and syrphid flies. Single-visit efficacy in terms of number of pods per raceme, number of seeds per raceme, 1000 seed weight and germination percentage revealed Megachile cephalotes as the most efficient insect pollinator followed by Megachile hera and Amegilla sp. Future studies should investigate the biology and ecology of these bee species with special emphasis on their nesting behavior and seasonality.