Response of cabbage (Brassica oleracea var. capitata L.) to different frequencies of irrigation and levels of soil fertilization in a non-saline coastal Typic Endoaquept

Abstract

Scheduling of irrigation and fertilizer dose is crucial for the sustainable production of cabbage. A field experiment was conducted to investigate the impact of irrigation and fertilizer schedule on cabbage yield during the Rabi season of 2015-16 and 2016-17 on a non-saline coastal soil of eastern India. The treatment comprised three different irrigation frequencies (I₁: eight irrigations, I₂: four irrigations, I₃: three irrigations) and three different levels of fertilizer (F₁: 100% RDF, F₂: 75% RDF, F₃: 50% RDF). The results revealed that all the growth, yield parameters and head yield (37.37 t ha⁻¹) were significantly higher in treatment I₂F₁. The highest yield of 43.03 t ha⁻¹ at 340 mm irrigation water was predicted from the water-yield production functional model. Maximum CWP and IWP (15.07 and 19.08 kg m⁻³, respectively) were recorded in the highest irrigation interval supplemented with 100% RDF (I₃F₁). A maximum fertilizer use efficiency of 309.4 kg kg⁻¹ of nutrient applied was obtained with moderate irrigation coupled with 50% RDF (I₂F₃). Soil depths of 0–30 and 30–60 cm accounted for 87.3% and 12.7% of the total soil moisture extraction, respectively. The highest residual available NPK in soil was found in treatment I₂F₁, while the lowest amount was recorded in I₃F₃. The maximum economic benefit (BCR; benefit-cost ratio) (4.51) was recorded under I₂F₁ treatment, whereas, treatment I₃F₃ observed the minimum BCR value (3.37). We recommend that four-irrigation scheduling complemented with 100% RDF could be the most effective and remunerative for the cabbage growers of non-saline coastal soils of eastern India under limited water supply conditions.