Early Sowing Date as A Cultivation Strategy to Alleviate Drought Effects On Yield Components of Different Canola Genotypes
Subject Areas : Stress Physiology
Nadia Gharechaei
1
*
,
Amir Hossein Shirani Rad
2
,
Nasser Shahsavari
3
1 - Department of Agronomy, Faculty of Agriculture, Karaj Branch, Islamic Azad University‎, Karaj, Iran
2 - Seed and Plant Improvement Institute (SPII), Agricultural Research, Education and ‎Extension Organization (AREEO), Karaj, Iran.‎
3 - Department of Crop production, Hajiabad Branch, Islamic Azad university, Hajiabad, Iran.
Keywords:
Abstract :
Water shortage or drought stress is an environmental factor that strongly affects crops productivity in various regions of the world. Sowing date as a factor affecting the growth and yield of oilseed crops can alleviate drought stress occurring in reproductive stage. To assess this, agronomic and physiological response of five canola genotypes (L1030, L1204, L1110, L1114 and Okapi) to drought stress were evaluated at two early and late sowing dates (7th and 27th October, respectively) as a two-year field experiment. Results showed that drought stress significantly reduced the seed yield and yield components of all genotypes at both sowing dates, which was a consequence of damage to photosynthetic pigments, reduction of relative water content. However, early sowing was able to alleviate drought stress effect; as seed yield of different genotypes at early sowing were 38-47% higher than late sowing. Moreover, the measured oil content was not influenced by drought stress and sowing date, so the highest oil content at both sowing dates were recorded in L1204 genotypes. Finally, the results showed that sowing of suitable genotype in the proper date could be an appropriate approach to canola sowing in semi-arid areas.