Yield, water use and water use efficiency of pigeonpea [Cajanus cajan (L.) Millsp.] under drip fertigation system

Abstract

Field experiments were carried out during two seasons (August-February) of 2011-12 and 2012-13 at Millet Breeding Station, Tamil Nadu Agricultural University, Coimbatore, to study the effect of drip fertigation on productivity, water use and water use efficiency of pigeonpea (Cajanus cajan) cv. LRG 41. The treatments included three irrigation regimes (50 %, 75 %, 100 % computed water requirement of crop) and surface irrigation along with three fertilizer levels with water soluble fertilizer (WSF) and conventional fertilizers (CF). The treatments were laid out in Randomized Block Design with three replications. The results revealed that drip irrigation at 100 % WRc with fertigation at 125 % RDF through WSF registered significantly highest grain yield of 2812 and 2586 kg ha-1 during 2011-12 and 2012-13, respectively. Surface irrigation with conventional method of fertilizer application recorded lower water use efficiency of 3.70 and 3.38 kg ha-1 mm-1 whereas it was reverse with drip irrigation of 100 % WRc + 125 % RDF through WSF with a WUE of 6.97 kg ha-1 mm-1 during 2011-12 and during second season (2012-13), the highest WUE of 6.72 kg ha-1 mm-1 was recorded in drip irrigation at 50 % WRc along with fertigation at 125 % RDF through WSF. The increase in grain yield with drip irrigation at 100 % WRc + fertigation with 125 % RDF through WSF was mainly attributed by greater and consistent availability of soil moisture and nutrients which resulted in better crop growth, yield components and ultimately reflected on water use efficiency and yield of pigeonpea Cajanus cajan.