Agronomic and Economic Evaluation of Mulching in Rainfed Maize—Wheat Cropping System in the Western Himalayan Region of India

Abstract

Mulching is highly beneficial for resource conservation under rainfed conditions, but non–availability of organic biomass and easy availability of fertilizers and herbicides has led to a gradual discontinuation of this practice. Various vegetative materials, including some troublesome weedy perennials, are available locally, which can be recycled for enhanced soil moisture and nutrient conservation. A field experiment was conducted at Dehradun, India, from 2001–2004 to study the effect of mulching with kudzu (Peuraria hirsuta), wild sage (Lantana camara), and subabul (Leucaena leucocephala) applied at 30 and 60 days of growth of maize (Zea mays), maize harvest, and sowing of wheat (Triticum aestivum). Application of 10 t/ha (fresh biomass) added 1.6–2.3 t dry matter through Peuraria, 2.5–3.2 t through Lantana, and 2.9–3.9 t/ha through Leuceana, which contributed 47.7–60.9 kg N, 58.4–70.9 kg N, and 118.4–148.4 kg N/ha, respectively. All mulching materials were beneficial and improved productivity of maize significantly by 16.6–20.6% over no mulching. Wheat yield also increased because of mulching in previous maize (+11.2%), and the beneficial effect was relatively greater (12.4–25.1%) when mulching was done at maize harvest or wheat sowing. Mulching showed improvement in organic C and total N status, and a decrease in bulk density associated with an increase in infiltration rate across three cropping cycles. Wheat gave three to five times more net profit than maize, and the net benefit-cost ratio of the system was the highest (1.34–1.35) when mulching was done at 60 days of maize growth with Peuraria and Leucaena. It was concluded that mulching with available vegetative materials in standing crop of maize or after harvest was beneficial for improving moisture conservation, productivity, and profitability of a maize–wheat cropping system under Doon valley conditions.