Response of Some Sugar Beet Varieties to Different Sowing Dates Under Two Seasonal Conditions in Khabat

The research was conducted in the field of Khabat Technical Institute / Erbil Polytechnic University during winter season of 2019-2020 and summer season of 2020. It shows the effect of planting date, varieties on growth and yield component of sugar beet under two different seasonal conditions. A factorial experimental design was applied in randomized complete block design with three replication; the first factor represents three planting dates (1st October, 16th October and 31th October, 2019) in winter and (1st March, 16th March and 31th March, 2020) in summer season, the second factor was three varieties of sugar beet (Germany, Turkish and Iranian), had been applied in both seasons. The combined effect of planting in 1st October and the Turkish variety produced the highest value of all study traits; No. of leaf.plant-1, leaf area (cm2), leaf area index (LAI), root length cm, root diameter cm, root weight kg.plant-1, root yield t.ha-1, sugar % and sugar yield t.ha-1in winter season, but the Germany variety surpassed in length of root (cm) in summer season. The interaction between planting date from 1st October with Turkish variety recorded the highest value of all study traits, in winter season achieved the lowest value in number of leaf.plant-1, root length cm, root diameter cm, root weight kg.plant-1, root yield t.ha-1, sugar% and sugar yield, were recorded from the interaction between planting in 31th March and Iranian variety in summer season. On the other hand, the interaction treatment 31th March with Turkish variety recorded the lowest value in leaf area and leaf area index.