تأثير اسيد جيبرليك بر روي شكستن خواب ميني تيوبرهاي سيب زميني رقم آگريا در آزمايشگاه و گلخانه

Effects of Gibberellic Acid on Breaking Dormancy of Agria Minitubers in Greenhouse and Laboratory

A randomized complete block design experiment with 3 replications was conducted to study the effect of 5 levels of gibberllic acid applications (0, 40, 80, 120 and 160 ppm) on breaking dormancy of potato mini tubers of Agria cultivars both in laboratory and greenhouse during 2005 and 2006. After breaking dormancy, traits like sprout number, length of largest sprout and days to sprouting were measured. Days to emergence, number of main stems and plant height were measured during growing period and tuber number per plant, total tuber weight and mean tuber weight after harvesting the crop. Results showed that gibberllic acid affected all traits, except sprout number and main stem per plant significantly. 40 ppm gibberllic acid concentration decreased days to sprouting significantly, while it increased largest sprout length as compared to control. Increasing gibberllic acid, on the other hand, decreased days to emergence and single tuber weight and increased plant height, tubers per plant and tuber yield. Application of 160 ppm concentration of gibberllic acid for breaking minituber dormancy increased tuber weight per plant significantly as compared to control treatment, while the difference between 160 and 120 ppm applications of gibberllic acid was not significant. Therefore, application of 120 ppm gibberllic acid can be recommended, because it breaks dormancy rapidly and increases sprouting induction, minitube number and tuber yield per plant.