EFFECT OF SOWING DATES AND PLANT DENSITY ON GROWTH CHARACTERISTIC OF TWO CORN VARIETIES(Zea mays L.)

Abstract

Field experiment was conducted out in spring season (2008) at two locations . The first at Agricultural Research Station in the Field Crops Department, University of Mosul and the second one at Twabzawa Village in Bashika (25 Km East Mosul) . The experiment was set out using Split-Split Plot Design in Randomized Complete Block Design (R.C.B.D) with three replications of each treatment . Four sowing dates (20/3, 5/4, 20/4, 5/5), three plant densities (250, 333 and 500 thousand plant/ha) and two varieties of corn (Bohoth 106 and Rabea) were used for each experiment .The most important results obtained from the reserch can be summarized as follows :All growth characters were significantly affected by sowing dates of corn at Colleg Research Station except for the Net Assimilation Rate (NAR) Whereas the following characteristic, leaves/plant, Crop Growth Rate (CGR) did not differ significantly by sowing datets at Twabzawa site .Most of the growth characters at the second sowing date (5/4) were superior to the same characters at other sowing dates at the Collage Station location, whereas at Twabzawa location the significant superiority for most growth characters was achieved at the 1st sowing dates .The results revealed that all growth characteristic except the NAR and R.G.R. was significantly affected by plant density at Twabzawa Location .The results showed that there were no significant differences between the variety Bohoth 106 and Rabea for all characteristic at both sites except that for CGR at Collagel Location.