ABSTRACT
A field experiment was conducted on a sandy clay soil at Agricultural Research Station, Basanthpur, Medak district of Andhra Pradesh during the kharif seasons of 2009-‘10 and 2010-’11 to study the variation in relative water content (RWC) of pigeonpea (Cajanus cajan (L) Mill Sp.) as influenced by plant densities and supplemental irrigation through drip. Three varied plant densities of pigeonpea (D1–55,555 plants ha- 1, D2–41,666 plants ha-1 and D3–33,333 plants ha-1) were tested as 3 main treatments with 4 irrigation levels as sub treatments involving control (I1 - rainfed), drip irrigation at flowering with 20 mm depth of water (I2), drip irrigation at pod development with 20 mm depth of water (I3) and drip irrigation at flowering and pod development with 20 mm depth of water at each stage, respectively (I4). The RWC was estimated at 15, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165 days after sowing and at harvest. Daily evaporation and rainfall were also recorded at the experimental site. The crop in lower plant density of D3 had higher relative water content in comparison to D2, intermediate and D1, higher plant densities at flowering and pod development stages irrespective of the irrigation treatments imposed. Further, supplemental irrigation at flowering and pod formation stages showed marginal rise in the relative water content irrespective of densities. Lowest relative water content was recorded under nonirrigated rainfed control (I1) at higher plant densities of D1 both at flowering and pod development stages.