EFFECT OF PLANT POPULATION DENSITY ON GROWTH AND YIELD OF GRAIN SORGHUM

Abstract

A factorial experiment was conducted at the experimental farm, Dept. of Field Crop Sciences, College of Agriculture/Abu-Ghraib-University of Baghdad during the spring and fall seasons of 2009. The aim was to investigate the effect of plant population density 27600, 53300, 107600 and 213300 plant. ha-1 and varieties(Inqath, Rabeh, and Kaffir) on growth traits of the grain sorghum and its relation to the grain yield and its components, Cultivars were significantly different in their Plant height where Kaffir gave significantly the highest average in each density of the four plant densities. The performance of cultivars Rabeh and Inqath for Plant height in both seasons was similar. Inqath was superior in the average number of leaf produced in spring and fall seasons, respectively. The three cultivars were significantly different in their tillers number during both seasons where Kaffir was superior in this character in each plant population density with the highest tiller number reached 2.20 and 1.44 tiller. Plant -1. The Rabeh cultivar had the highest flag leaf area reached 466.13 and 716.15 cm2, compared with 166.39 and 225.58 cm2 for Kaffir cultivar in both seasons, respectively, Grain yield of three cultivars was not significantly different in spring season, while in the fall season, Kaffir was superior giving 5.85 t. ha-1 compared with 5.48 and 4.59 t. ha-1 for Inqath and Rabeh, respectively. For biological yield the Superiority was to Rabeh over other cultivars in spring season only reached the average of yield 17.30 t. ha-1 compared with 16.76 and 13.74 t. ha-1 for Inqath and Kaffir, respectively. It is concluded that the total plant grain yield responds to the changes in growth traits of cultivars. Kaffir had the less biological yield but it gave the highest grain yield in fall season. This may be attributed to the contribution of tiller in this trait where Kaffir possessed the highest average of tiller number and the highest percentage of contribution of the tiller in grain yield in the fall season.