Effect of plant density on grain yield and some qualitative characteristics of five durum wheat (Triticum durum) genotypes under Ahvaz climatic conditions

In order to determine the suitable plant density and genotype of durum wheat (introduced by Agricultural Research Center of Khuzestan) in terms of qualitative and quantitaive characteristics, an experiment was conducted in Ahvaz, Iran in 1977/98 cropping season.The recorded characteristics were included yellow berry,protein quality, protein percentage of grain, no. of spikes per m2 and grain yield. Among the five genotypes studied (Shwa/Mald,Chen/Altar,Altar84,Gediz and Aconchi 89), Chen/Altar showed the highest percentage of yellow berry (11.53%) and Shwa/Mald the lowest (2.3 %).Shwa/Mald had the highest protein quality with Zeleny number of 35.3 and Altar 84 had the lowest protein quality with Zeleny number of 29.4. Shwa/Mald had also the highest protein percentage (13.7 %) among the five genotypes. Plant density of 400 and 500 plants/m2 resulted in the highest (8.5) and 200 plants/m2 the lowest (3.2) percentage of yellow berry. Plant density of 200 and 500 plants/m2 had the highest and the lowest grain protein with 13.1% and 12.3%, respectively. In spite of increase in protein quality at lower density there was no any significant differences among the plant densities. As density increased, grain yield also increased. The highest grain yield was obtained at 500 plants/m2 (5678 kg ha-1) and Chen/Altar had the highest yield among the genotypes (4976 kg ha –1).There was significantly negative correlation between grain yield and protein quality (p<0.05) and protein percentage (p<0.01). However, significantly positive correlation(p<0.01) was observed between grain yield and yellow berry. This study showed that Shwa/Mald with 500 plant m-2 can be recommended for Ahvaz climatic conditions.