Effect of Leaf Defoliation on Some Agronomical Traits of Corn

Abstract: Many factors are involved in estimating total loss of yield potential. These include effects from defoliation, stand loss and plant bruising and environmental condition during the remainder of growing season. Therefore, to evaluate the influence of leaf defoliation on agronomical trials of corn (Zea mays (L.)), a factorial experiment (design:RCB), consisting of three growth stages of maize(vegetative, tasseling and flowering) and five levels of leaf defoliation (0,25,50,75 and 100%) replicated three times in 2011 at agricultural meteorological station of miandoab (West Azar. Iran). Results revealed that Plant height and ear height was significantly affected by leaf defoliation. Interaction of leaf defoliation×growth stages on seed depth, 1000-grain weight and grain yield was significant. Seed depth decreased significantly by increasing leaf defoliation only in flowering stage (-0.03 mm/1%D). Leaf defoliation diminished 1000-grain weight and grain yield in all growth stages, thought slope of decreasing in flowering stage was more than others stages. Overall, research demonstrated that flowering stage is more sensitive to leaf defoliation than tasseling and vegetative stage in corn.