STUDIES OF SOME FACTORS AFFECTING CORN PRODUCTION

Abstract

Two separate field experiments were carried out during 1999 and 2000 seasons, at the Agricultural Experiment and Research Station, Faculty of Agriculture, Cairo University at Giza, Egypt to study: 1- The effect of N fertilization treatments (mineral as urea (46.5% N) with farmyard manure (FYM) as cattle manure) and plant population density (20000, 25000 and 30000 plant/fed.) on growth, yield and its components of maize (part 1). 2- The effect ofN sources (urea 46.5%, poultry and cattle manure) and N levels (0, 90, 120 and 150 kg N/fed.) on previous crop and characters (part II). Single cross 10 was used in both experimental parts. The most important results of first part are abstracted as follow: 1- In general, the most studied characters increased by raising the quantity of N from urea. However, the differences between 120 kg N/fed. as urea alone and 90 kg N/fed. as urea+ 30 kg N/fed. as cattle manure were insignificant in most characters. 2- Increasing plant population density !Tom 20000 to 30000 plant/fed. significantly increased plant height, number of green leaves per plant, time of 50% tasseling and silking, ear height, LA!, COR, RGR, ears yield, grain yield, straw yield and biological yield. 3- The interaction between N fertilization combinations and plant population density had a significant effect on all studied characters. Optimum grain yield/fed. was obtained by planting 30000 plant/fed. with 120 kg N/fed. as urea, followed by 60-90 kg N as urea combined with 30-60 kg N as organic source (cattle manure). Results of the second part are abstracted as follow: 1- Highest values of most growth and yield characters were obtained by using N as urea followed with poultry manure, among which the differences were insignificant in most cases. 2- Increasing N levels up to !50 kg N/fed. significantly increased all growth characters, yield and its components. 3- The interaction between N sources and N levels had a significant effect on all studied characters. The highest grain yield was obtained by using !50 kg N/fed. as urea, followed by !50 kg N as poultry manure as organic source without significant difference between them. Highly significant positive correlation coefficient were obtained between grain yield per feddan and most important characters especially number and grain weight per ear as well as shelling percentage in both first and second parts.