Effect of Planting Date on Seed Yield and Its Components of Mungbean (Vigna radiata L.) Genotypes in Varamin Region in Iran

To study the effect of planting date on seed yield and its compoments of suitable and high yielding mungbean genotypes a field experiment was carried out as factorial arrangement in randomized complete block with three replications in 2007 and 2008 in Varamin Field Station، Varamin، Iran. Experimental treatments included: five planting dates; 04 May، 19 May، 03 June، 17 June and 03 July، and four mungbean genotypes; cv. Parto، cv. Gohar، and 1-6-16 and NM-94 promising lines. Combined analysis of variance revealed that the 19 May planting date (mean temperature 24 ºC) had the highest seed yield (1805 kg ha-1) and 03 July planting date (mean temperatute 30 ºC) produced the lowest seed yield (1350 kg ha-1). NM-94 promising line had the highest seed yield (1809 kg ha-1) and cv. Gohar produced the lowest seed yield (1371 kg ha-1). Genotype × planting date interaction showed that 1-6-16 promising line had the highest seed yield (2089 kg ha-1) in 03 June planting date (mean temperature 25 ºC) and significantly differed from other treatments. The lowest seed yield (1170 kg ha-1) belonged to cv. Parto in 19 May planting date.