عنوان مقاله [English]
In this study, analysis of actual data collected from sugar beet hybrid monogerm seed producers in the 2001 growing season and laboratory seed samples showed that delay in steckling sowing resulted in the reduction of raw and pure sugar beet seed yield and the increase of undersize seed portion. Non-significant effect of sowing dates on unkernel seed percent showed that the high temperatures with low relative humidity conditions were synchronized with only sugar beet seed growth period in present year. Late steckling sowing in the 2001 growing season, due to synchronization of sugar beet seed growth stage with critical agroclimatical conditions, increased the undersize seed portion which resulted in the pure seed yield reduction. Results of long-term prediction of probability of critical conditions occurrence showed that from 05 July to 02 August of every year in Ardabil region, sugar beet seed-bearing plants growth may be concurrent to blasting conditions and the probability for this is 70%. Therefore, providing wet-conditions in the soils of sugar beet production farms is an effective manner to decrease the losses due to blasting.