EFFECT OF CULTIVARS AND PLANTING DATE ON THE GROWTH AND YIELD OF SUNFLOWER

Abstract

ABSTRACT This study aimed to improve the germination and growth of the pollen tube, increase fertility rates, and enhance seed yield and its components for the sunflower crop. A field fall experiment was conducted during the 2023 and spring 2024 seasons using split-plot arrangements witm Randomized Complete Block Design (RCBD) and four replicates. The main factor were planting dates (June 1, 10, 20, 30, and July 10 for fan, and February 18, March 1, 10, 20, and 30 for spring), while the secondary factor were three oilseed sunflower Cultivars (Aqmar, Flamme, and Sakha). The results showed that the February 18 planting date achieved the highest fertility percentage (97.04%) and seed yield (4.892 Mg ha⁻¹), July 10 recorded the highest 1000-seed weight (85.72 g), and June 1 achieved the highest biological yield (38.655 Mg ha⁻¹). Flamme outperformed in most traits, while Sakha recorded the highest harvest index (12.36%). The results indicate that genetic and environmental variability improved Cultivars productivity, recommending Flamme for planting on June 1 and February 18.