YIELD, QUALITY AND SHELF LIFE OF JUTE (Corchorus olitorius) SEED AS INFLUENCED BY POTASSIUM AND BORON

Abstract

Acute shortage of quality jute seeds (Corchorus olitorius) accentuated conduction of this study in order to find out appropriate doses and proper application of potassium (K) and boron (B) in quest of increasing seed production and improving seed qualities for longer duration of storage. To achieve these objectives, a research plan was made with three experiments conducted at the Jute Seed Production and Research Center, Nashipur, Dinajpur during July 2007 to December 2008. First experiment had the target for selecting appropriate dose and methods for K application from amongst six levels of K (0, 30, 60, 90, 120 & 150 kg ha!) applied in three ways -(i) all K as basal at final land preparation, (ii) half as basal and rest half as top dressing at 30-35 days after sowing (DAS), and (iii) one- third as basal one third at 25 DAS and one- third at 45 DAS as top dressing. Of all the parameters studied, the following six -(i) shoot dry matter yield, (ii) seed yield, (iii) seed quality (viability, vigour, seedling dry matter, EC, soluble protein, soluble sugar), (iv) seed shelf life (deterioration of seed quality as in (iii), (v) benefit cost ratio (BCR), and (vi) K and B, balance in soils, were used for selection of better treatments. Out of 16 treatments, only basal applications of 30, 60, and 90 kg K ha" were selected from the first experiment. The second experiment was conducted parallel to first experiment with four levels of B (0, 1, 2, & 3 kg ha‘) for application as - (1) basal (2) half as basal and half as top dressing at 35 DAS, (3) half as basal and half at 35 DAS as foliar spray, (4) one- third as basal, one third at 25 DAS and one- third at 45 DAS as top dressing, and (v) one- third as basal, one -third at 25 DAS and one- third at 45 DAS as foliar spray. Of the 16 treatments, basal applications of 1, 2 & 3 kg B ha were selected on the basis of their overall performances. The third experiment was carried out with 16 treatment-combination of K (0, 30, 60 and 90 kg ha") and B (0, 1, 2 and 3 kg ha-!) moduled form the finding of earlier two experiments. Basal application of K and B had significant positive effect on seed yield and seed qualities. They had beneficial effect on the degree of seed leachate conductivity, seedling dry weight and essaying vigour. Application of 60 or 90 kg K ha* along with 1 or 2 kg B ha did not differ significantly in respect of increasing seed yield (62.2-69.0% increase), seed viability (97.5-99.0% germination), EC (317-354 up S cm), vigour (98.33-98.50), seedling dry weight (0.966-1.023 g plant"), % protein in seed (22.2-22.5%), % sugar in seed (13.4-13.6%) and BCR (1.24-1.36). Seeds stored in air tight plastic pot retained good germination (more than 90%) up to 9 months in place of only 6 months for no application of K and B. Use of 60 or 90 kg K ha* with 1 or 2 kg B ha? may ensure safe storage of seeds up to one year having only some deterioration like a decrease in seed germination (7.07-9.09%) vigour (5.95- 7.70%), total soluble protein (4.41-8.42%) and total soluble sugar (5.16-7.95%). The highest seed yield and BCR (997.67 kg ha! and 1.36, respectively) were recorded for the application of 60 kg K + 2 kg B per hectare with a negative balance of 32.6 kg K hat anda positive balance of 1.44 kg B ha" with the corresponding values of 966.8 kg ha-! with 1.24 BCR, and a positive balance of K (1.32 kg ha!) and B (0.514 kg ha") with the application of 90 kg K + 1 kg B per hectare. Therefore, it is inferred that basal application of 90 kg K ha-! + 1 kg B ha? can be a recommendation for producing increased amounts of quality seeds of Corchorus olitorius leaving a positive balance of both K and B in soils.