Seed agronomy of jute. I. Production and quality of Corchorus olitorius seed as influenced by seed size used at planting.

The study investigated the impact of variation in seed size at planting on the production of jute seed and its quality. Field experiments with five treatments of seed sizes viz. large (> 1.201 mm), medium (1.201-1.000 mm), small (1.000-0.954 mm), very small (< 0.954 mm) and ungraded were studied in a randomised block design during May-November, 1994 and 1995. Harvesting was done at full maturity of pods. Seed quality components of the graded produce were assessed in the laboratory and green house using completely randomised designs. The results suggest that increase in the size of seed at planting was beneficial in terms of plant growth and components of seed yield and its quality (production of large and medium seeds, emergence. emergence rate index, seed weight, seedling dry matter and seedling vigour index of the graded produce). In general, large and medium sized seeds excelled over ungraded, small and very small seeds. The difference between large and medium seeds was, however, not apparent, The superiority of large and medium seeds over others in terms of plant growth, seed production and quality may be attributed to increased seed weight with high initial capital of food reserves causing greater absolute growth rate of seedlings and plants.