Effect of planting date on the yields of sugar beet variety in winter sown planting

摘要

Water is the main limiting factor in expanding spring sown sugar beet production in Iran. Compared to spring sown sugar beet, autumn sown sugar beet is of much higher economical viability and water use efficiency, and Therefore some experiments have beenconducted on the possibility of the winter sown sugar beet in the sugar beet research center of Khorasan Razavi province in order to develop the winter sown sugar beet in this province and to find new climates. Due to the importance of the determinationof variety and the optimum planting date, five varieties (i.e. Sharif, Giada, Spartak, Merack and Monocota) were evaluated during this experiment at two planting dates 2015/September/23; 2015/October/12) in terms of the Split Plot design with three replication in 1394. Results showed that the effect of variety on bolting was significant at 1%. Bolting on the Giada variety as a resistant variety was as much as about 90% compared to the Sharif one. Effect of the planting date on the root, sugar and whitesugar yields were significant with 1 %. At an earlier planting date, Giada's variety had the lowest bolting (0.25) and the highest root yield (5468 ton/ha) in the winter sown planting of sugar beet in Mashhad region.