Yield and some Traits of Forage Sorghum Genotypes in Different Planting Dates in Shahrekord Region

Sorghum is a forage crop that produces high yield of dry matter. Forage sorghum is used for production of silage and dry folder. To evatuate forage yield potential of forage sorghum genotypes in different planting dates, this experiment was carried out in Shahrekord during 2013 and 2014. The experiment was arranged in split plot with three replications in that, main plots were three planting dates (26 may, 10 June and 25 June) and sub plots were four sorghum genotypes (cvs. Pegah and Spead Feed and lines KFS1 and KFS2). Forage yield and different traits were recorded during the growth period. The results indicated that fresh and dry fodder yields in two years were not significantly different. The highest fresh and dry fodder yields were obtained from the first planting date treatment (78.86 and 16.89 tha-1, repectively). The highest plant height and diameter of stem were also belonged to the fisrt planting date. The higest fresh and dry fodder yields were Produced by line KFS1 (73.08 and 16.30 tha-1, respectively) which were not significantly different from those of Pegah cv. (P ≤ 0.05). Significant difference was not observed for protein contents in different planting dates. The highest protein contents and lowest NDF and ADF were obtained from cv. Speed Feed. Generally, the results revealed that in three planting dates, sorghum genotypes could produce reliable forage yield, even that, the third planting dates produced less yield than other two planting dates.