Effects of previous legume crop levels of nitrogen and sowing date on yield components and some morphological characteristics of corn

Abstract

This study was conducted in order to determine the effect of different previous crops and sowing dates on the grain yield and some other yield components of corn under typical Mediterranean climatic conditions during summer period of 2013 and 2014. The experiment was laid out in a split-plot design in the form of randomized complete blocks with three replications. The main plots were allocated to three sowing dates (Early Spring, Mid Spring and Late Spring) and sub-plots to previous crops (Vicia sativa, Vicia villosa, Lathyrus sativus, Trifolium resupinatum and Pisum arvense) and three different controls without previous crop (control-1: 100 kg ha-1 N; control-2: 200 kg ha-1 N and control-3: 0 kg ha-1 N). Corn grain yield, yield components (number of ears per plant, number of seeds per ear, ear length, ear diameter, 1000-grain weight) and plant height were assessed. The results showed that late planting date had a significantly negative effect on tested traits and second planting date (mid- spring) produced higher corn grain yield compared to the other dates. The highest corn grain yield (11011 kg ha-1) also occurred in control-2 (200 kg ha-1 N without previous crop) treatment and was significantly different from the other previous crop treatments with 100 kg ha-1 N and controls except Vicia villosa as previous legume crop of which corn grain yield was comparable with it.