Influence of irrigation levels and mulching on growth, water use, yield, economics and quality of potato (Solanum tuberosum) under new alluvial soil of West Bengal

Abstract

The field trials were conducted on sandy-loam soil of District Seed Farm, Adisaptagram, Hooghly, West Ben- gal, during 3 consecutive winter seasons of 201112, 201213 and 201314, to study the performance of Kufri Jyoti potato (Solanum tuberosum L.) under different irrigation levels and mulching under West Bengal region of Eastern India. Growth attributes increased in all the irrigation treatments over the control, and irrigation at 20 mm cumulative pan evaporation (CPE) performed the best. Mulching also resulted in higher growth attributes over no- mulch situation. All the irrigation levels recorded higher tuber yield (grade-wise as well as total) over the control, and the total tuber yield was the highest (32.31 t/ha) with irrigation at 20 mm CPE. Consistent decline in yield (24.43 to 88.39%) was recorded with the decrease in irrigation frequency, while water-use efficiency increased lin- early from 80.78 to 114.33 kg/ha-mm in response to water stress. Maximum net income and benefit: cost ratio were recorded with the crop irrigated at 20 mm CPE, accounting 179 and 54% more over the control treatment re- spectively. Irrespective of irrigation levels, crops in mulched plots (with paddy straw @ 5 t/ha) resulted in higher net returns and benefit: cost ratio than those crops in no-mulch plots. The plots irrigated thrice at critical stages (control) recorded 22.3, 50.7 and 15.4% higher available N, P and K content, respectively over the plots irrigated at 20 mm CPE. Quality characteristics like dry-matter content, specific gravity, crude protein, ash content, starch and vitamin C content increased with decreased frequency irrigation. Potato cultivar Kufri Jyoti may be irrigated at 20 mm CPE in combination with paddy straw mulching @ 5 t/ha for higher table-purpose potato tubers, total yield and better quality of tubers.