Influence of sowing dates on biochemical and seed yield parameters in Chandrasur (Lepidium sativum Linn.)

摘要

A field experiment to measure the influence of varying sowing dates on some biochemical and seed yield parameters in Lepidium sativum was conducted during Rabi cropping season at JNKVV, Jabalpur. The five sowing treatments consisting of sowing on 14thOctobar (D1), 21th Octobar (D2), 29th Octobar (D3), 6th November (D4) and 14th November (D5) were placed in a randomized block design with four replications each. The chlorophyll a, b and a+b contents in plant leaves measured after 30, 60, 75 and 90 days of sowing (DAS) varied greatly in crop raised through different sowing dates. At 30DAS growth stage chlorophyll-a was maximum (0.95mg/g. f wt.) in crop raised through D1 sowing. However at 75 and 90 DAS, maximum chlorophyll-a levels were recorded in the leaves of crops raised via D4 (0.45 mg/g.f.wt.) andD3 (0.46 mg/g.f.wt.) treatments, respectively. Chlorophyllb levels, on the other hand, was maximum in leaves of D1 treatment (0.88 mg/ g. f. wt.) after 30DAS but, after 60, 75 and 90DAS it was highestin plants of D3 sowing (0.87, 1.15 and 0.86 mg/g.f. wt., respectively). Therefore, when sowing date treatments were compared on the basis of total chlorophyll a+b levels, leaves of crops raised through D1 recorded the maximum value of 1.83 and 1.33 mg/g.f.wt. after 30 and 60DAS and those of D3 after 75 and 90DAS (1.58 and 1.32 mg/g/f/wt, respectively). Different sowing dates also casted significant influence on nutrient status of seeds at maturity. 14th October sown crop out-performed over other sowingdates in context to highest nutrient estimates; protein (8.03%), carbohydrates (3.92%), fat (18.00%), fibre (19.15%), ash (6.41%), mucilage (10.19%) and moisture (3.03%). However, the maximum percentage of sinapic acid (0.0138%) was registered when cropwas sown on 21st of October. D1 treatment resulted in highest economic returns in terms of maximum biological (7159 Kg. ha1) as well as seed yields (916 Kg.ha1) and harvest index (12.80%) and is, therefore, recommended to be the optimal sowing time for Lepidium sativum under Jabalpur climate.