تأثیر تنش شوری خاک، بر برخی صفات رویشی و زایشی ارقام آفتابگردان روغنی در شرایط آب و هوایی مهاباد

To evaluate the effect of soil salinity stress on some vegetative and reproductive traits of sunflower (Helianthus annus L.) oil varieties in Mahabad conditions, a factorial experiment was conducted in greenhouse condition based on randomized complete block design with five replications in 2009. Treatments were included five levels of soil salinity (EC: 0.5 (as control), 2, 4, 6 and 8 ds /m) and 4 cultivars (Zarya, Armavirisky, Master and Record). Results showed the significant effect of soil salinity and cultivars on stem diameter, leaf chlorophyll, number of leaflets around the head and grain/shell ratio was significant. Interactions between soil salinity and cultivars was also significant on 1000 seed weight, oil percentage and oil yield per plant. Means comparison showed that with increasing soil salinity, trends of all traits was decreased, except 0 grain/shell ratio. The highest stem diameter was observed at control treatment (1.14 cm) and Armavirisky cultivar (1.15 cm), the highest leaf chlorophyll was obtained from 8 ds/m of soil salinity (1.29) and in Armavirisky and Zarya cultivars (1.17), the highest number of leaflets around the head was observed at control treatment (7.18) and in Record cultivar (7.76) and the highest grain/shell ratio was obtained from 8 ds/m of soil salinity (47%) and in Master cultivar (42%). In addition, the 1000 seed weight (36.91 g) was belonged to the control soil (EC: 0.5 ds/m) and Armavirisky cultivar. The highest oil percentage (48.47 %) and the highest oil yield per plant (1.43 g) were belonged to the control soil and Armavirisky cultivar. In general results showed that Armavirisky and Record cultivars having the highest 1000 seed weight, oil content and oil yield in the salinity conditions were better than Zarya and Master.