Seed Invigoration Techniques to Improve Germination and Early Growth of Sunflower Cultivars

Abstract

Sunflower (Helianthus annuus L.) is one of the most important oil crops worldwide. Due to high oil content, sunflower achens often posse's low germination and vigour. An effective pre-sowing treatment to enhance the germination and vigour is required. So it was imperative to develop suitable techniques in order to improve sunflower achen germination capacity. Achens priming is now a widely used commercial process that accelerates the germination rate and improves achenling uniformity in many crops. A laboratory study was conducted to find out the influence of achens priming treat- ments on germination and achenling vigour as well as some physiological characters of two sunflower cultivars (Giza 102 and Sakha 53). Achens priming using ascorbic acid at 75 mg/L and folic acid 20 mg/L recorded the maximum emergence percentage and minimum mean emergence time in Sakha 53 and Giza 102 cultivars, respectively as compared with unprimed achens. In most cases, priming strategies improved the achenling vigor in terms of shoot and root length and dry weights, and shoot to root ratio. Compared with control, in Sakha 53 cultivar, achenling vigour parameters were higher at 20 mg/L folic acid and 75 mg/L ascorbic acid for both for Giza 102 and Sakha 53, respectively. Moreover, all priming technology in- creased all physiological characteristics as compared with control. Therefore, it could conclude that achens primed with ascorbic acid or folic acid solution of may be used for sunflower achen invigoration.