Effect of sowing date and abscisic acid on sunflower growth, seed yield and germination

Abstract EN

Sunflower is an important field crop.

However, heat stress decreases seed quality and productivity of it.

The aim of this study was to enhance growth, seed yield and germination of the crop throgh applying different sowing dates and spraying abscisic acid.

This work was carried out at Department of Field Crops Research Station- College of Agriculture- University of Tikrit.

It included two factors, three sowing dates (1/3, 15/3 and 30/3) and four concentrations of abscisic acid (0, 50, 150 and 300 mg L-¹).

The experiment was applied using Randomized Complete Block Design (RCBD).

Results showed a significant effect of the two factors and the interaction between factors on all the studied characteristics except the impact of sowing date on seed germination and speed.

The highest values of means were at early planting and the highest concentration of abscisic acid.

Early planting and application of abscisic acid under heat stress supports the growth, seed yield and germination of sunflower crop.