Influence of dates of planting and mulching on growth and tuber yield of potato (Solanum tuberosum) in rice (Oryza sativa) fallows of shallow lowland of Asom

Abstract

A field experiment was carried out during the winter (rabi) season of 2010–11 and 2011–12 at the research farm of Regional Rainfed Lowland Rice Research Station, Gerua, Asom, to study the effect of dates of planting and mulching on growth and yield of potato (Solanum tubersoum L.) in rice fallows of rainfed shallow lowland ecosystem. The treatments consisted of 6 dates of planting, viz. 30 October, 10 November, 20 November, 30 November, 10 Decemer and 20 December in main plots and with and without mulch in subplots. Growth and yield attributes like days to emergence, plant height, leaf-area index, tubers/plants, tuber yield and dry-matter content of tubers showed significant response to different dates of planting. Planting on 30 November registered higher plant population, tubers/plant and tuber dry-matter which resulted higher tuber yield (13.91 t/ha) than early or late planting. Early planting on 30 October recorded poor tuber yield of 7.92 t/ha which was due to poor crop stand. The yield components and yield of potato were positively influenced by the use of paddy straw mulch. Mulch with paddy straw recorded 24% increase in tuber yield over no mulch. Higher yield of potato under mulch might be owing to better crop stand, higher percentage of large tubers and better tuber dry matter. Common scab affected tuber percentage was significantly less in 30 November-planted plots (20%) as compared to other planting dates. Mulch with paddy straw reduced the incidence of common scab by 16% over no mulching.