Physiological impact of irrigation water deficit and plant density on maize yield and yield components

Maize (Zea mays L.) crop was grown at Coimbatore in the year 2009 during kharif season. The treatments imposed were three soil moisture levels, 100% irrigation water supply (0.8 IW/CPE ratio), 75% irrigation water supply (0.6 IW/CPE ratio), 50% irrigation water supply (0.4 IW/CPE ratio) and plant density treatments adopted were normal spacing (60×20 cm), narrow spacing (30×30 cm), reduced narrow spacing (45×20 cm) levels. Increasing the plant density which cause by the change in plant population per unit area that increase the yield of maize even the reduction in soil moisture levels. But further reduction in soil moisture and narrow spacing causes yield decrease. The individual treatments of normal irrigation practice, narrow plant spacing and its combinations were registered better performance on kernel, stover yield. From the correlation studies the relative water content of leaf (90.7%) followed by the yield components such as filled kernel number (67.0%) and 100-kernel weight (66.9%) were highly correlated with the kernel yield of maize.