↵​Effect of Drip Irrigation Combined Organic Mulching on Water Productivity and Yield of Tomato (Lycopersicon esculentum L.)

Abstract

Background: The main challenge confronting both rainfed and irrigated agriculture is to improve water use efficiency (WUE) and sustainable water use for agriculture. A field experiment was conducted during early summer season of 2020 to study the effect of drip irrigation combined with organic mulching on soil moisture, growth, yield of tomato grown on alfisols at the college farm of College of Agricultural Engineering, Madakasira, Ananthapuramu district of Andhra Pradesh. Methods: The experiment was laid out in completely randomized block design (CRBD) with seven treatments comprising of various organic mulches. The treatments were T1 - Sawdust + Irrigation based on daily crop water requirement, T2 - Ragi straw + Irrigation based on daily crop water requirement, T3 - Groundnut shells + Irrigation based on daily crop water requirement, T4 - Groundnut shells + Irrigation once in every two days, T5 - Saw dust + Irrigation once in every two days, T6 - Ragi straw + Irrigation once in every two days and T7 - Control (without mulch) + Irrigation based on daily crop water requirement. All the treatments were replicated thrice. The plot size of each treatment was 4m × 2.5m. Result: The results revealed that throughout the crop growth period, T3 - Groundnut shells + Irrigation based on daily water requirement maintained soil higher moisture content to an extent of 132-146% as compared to control T7 (Control + Daily water requirement). The fruit yield obtained with T3 - Groundnut shells + Irrigation based on daily water requirement was significantly higher (8.8 t/ha) as compared to control T7 (Control + Daily water requirement) (7.6 t/ha). The highest water use efficiency (39.6 kg/ha/mm) was noted with T4 - Groundnut shells + Irrigation once in every two days), whereas T7 (Control + Daily water requirement) registered minimum WUE (16.3 kg/ha/mm). Weed dry matter and weed index was found to be higher (50% to 100%) in T7 (Control + Daily water requirement) throughout the crop growth period as compared to all the treatments applied with organic mulches. Our results indicated that T3 - (Groundnut shells + Irrigation based on daily crop water requirement) resulted in the highest plant height, number of fruits per plant and high water use efficiency as compared to without mulching. Further, under irrigation water constraints, groundnut shells mulch and drip irrigation once in two days was found to be effective in attaining higher WUE.