Sugar beet autumn- sowing in warm region of Esfahan and Khozestan(Izeh) provinces.

Autumn sugar beet sowing in dry areas such as Iran, in comparison with spring sowing, needs less amount of water: a better choice for using winter water and a resolution for the water-stress crucial problem. The experiments were done for the evaluation of winter beet production in years of 2006 and 2007 in two areas Aran and Bidgol (in Isfahan province) and Izeh (in Khuzestan province), located in the areas of two sugar factories of Chahar-Mahal and Isfahan. In so doing, the effects of sowing dates (November 8 and, November 29, 2006) and harvesting dates (May 13 and May 23, 2007) on yields quality and quantity of two varieties (one Iranian and the other foreign) were studied. In Aran and Bidgol areas, the root yields of the two varieties showed no significant difference, but the sugar content of Iranian variety, because of bolting, was nearly reduced %2, the sugar yield was then decreased. Consequently, extractable sugar content in Iranian variety, showed %6 reduction resulting in less white sugar yield. In Izeh, the Iranian variety, in both of sowing dates, showed more root yield, sugar yield and white sugar yield; however, the increases were not significant. With elongation of the growing period, root yield, sugar yield and white sugar yield had an increase and with shortening of the growing period the root yield significantly had a decrease. The lowest root yield at the sowing date of November 29 and harvesting date of May 12 was recorded (duration 135 days). The highest root yield, sugar yield and white sugar yield on sowing date of November 8 and harvesting of May 23 (duration 218 days) was observed, 49,92, 9,45, 7,63 ton/hectare respectively, which showed a significant difference in respect with the other treatments. Also it was determined that the harvesting time in this area could be very important and one month earlier harvesting could significantly reduce the root yield, sugar yield, and white sugar yield. In Izeh (in comparison with Aran and Bidgol) less bolting percentage was observed, whose cause was the less severe coldness of the area. In Izeh, the bolting in the Iranian variety on the first sowing date and harvesting date was %1, which with the delay in harvesting, bolting increased to %5. In Aran and Bidgol the Iranian variety had %15,38 bolting, while in the foreign variety there was no bolting at all. The results of this study proved that the autumn sugar beet sowing in Aran and Bidgol and Izeh, in the case of using the bolting-resistant varieties, is possible, but for the optimum production and use of water and soil resources of these areas, more study and research on autumn sowing is required.