Temporal variation in phonological and agronomic traits of some irrigated facultative/winter bread wheat (Triticum aestivum L.) cultivars released between ۱۹۴۳ and ۲۰۱۱ in Iran

A field experiment was conducted at the Seed and Plant Improvement Institute Research Field Station in Karaj, Iran, during the ۲۰۰۹-۱۰ and ۲۰۱۰-۱۱ growing seasons to estimate genetic progress and the variation in penological and agronomic characteristics in ۱۳ irrigated facultative/winter bread wheat (Triticum aestivum L.) cultivars released in Iran between ۱۹۴۳ and ۲۰۱۱. Trends of temporal variation of the traits measured revealed that grain yield and some related phonological and agronomic traits have increased in the more recently released cultivars. Thousand grain weight decreased slightly compared to older cultivars. Number of days to heading and anthesis decreased in new cultivars, butgrain-filling period and days to physiological maturity did not change. Spike length also increased but plant height decreased in more recently released cultivars. These changes may explain the increase in grain yield of newly released facultative/winter bread wheat cultivars.

کلیدواژه ها:

agronomic characteristics ، Bread wheat ، days to flowering ، grain filling duration ، thousand grain weight