EFFECTS OF PLANT DENSITY AND PLANTING DATE ON LEAF NUMBER AND SOME DEVELOPMENTAL EVENTS IN CORN

The effects of plant density on leaf number and some developmental events in 4 corn hybrids were studied in 1969 and 1970. Increase in plant density was accompanied by a decrease in leaf number, an increase in the periods from planting to tassel emergence and mid-silk and an increase in grain moisture at harvest. High linear correlations between leaf number and these developmental events were obtained within the spacing environments. The effects of 8 planting dates on leaf number and some developmental events were studied in 1970. Delayed planting was accompanied by changes in leaf number, with a significant increase in leaf number at the middle planting dates, a decrease in the periods from planting to tassel emergence and mid-silk and an increase in grain moisture at harvest. Leaf number was highly significantly correlated with these developmental events within the planting date environments.