Effects of planting date and corm size on flower yield and physiological traits of saffron (Crocus sativus L.) under Varamin plain climatic conditions

In order to evaluate the effect of different planting dates and the corm size on yield and some physiological characteristics of saffron، an experiment was conducted as factorial in a randomized complete block design with three replications at the Research Farm of College of Abouraihan، University of Tehran، is located in Varamin dry plain during growing season 2013-2014. Four planting dates، 10 June، 7 and 27 September and 12 October and two corm sizes 5-9 g and 10-14 g were considered as treatments. Evaluated physiological traits include such as proline and protein content in leaves and yield traits، include number of flowers and dry weight of stigma were measured and were examined in a square meter and starting date of flowering were recorded. The results of this research showed that cultivation of large saffron corms (10-14 g) on planting date of 10 June، had Maximum yield، by production 62. 7 number of flower and 0. 299 gram dry weight of stigma in a square meter. Leaf proline concentration of small saffron corms (5-9 g) on planting date of 12 October and leaf protein concentration of small saffron corms (5-9 g) on planting date of 10 June، were higher than the other planting dates. Increasing proline concentration increased plant resistance under drought and cold in corms planting on 12 October، particularly small corms. In general، these results indicate that flower yield in first year is more influenced by corm size and planting of large corms (10-14 g) on 10 June will have a suitable production.