Bazı priming uygulamalarının marul tohumlarının yüksek sıcaklıkta çimlenme ve çıkış performansları üzerine etkileri

The maximum temperature range for lettuce (Lactuca sativa L.) germination is 25° to 30°C. Temperatures above this optimum temperature range inhibit germination of imbibed lettuce seed and causes non-uniform stand establishment. The germination failure of completely imbibed lettuce seed due to the high temperature is termed 'thermodormancy'. One of the effective methods to overcome this dormancy is seed priming. The effects of incorporating Prohexadione-Calcium (Pro-Ca) into priming solutions on germination and emergence performances of lettuce seeds at 20, 30, and 35 °C were investigated. Priming was accomplished by imbibing lettuce seeds for 20 h at 15 °C in darkness in solutions of KNO3 or KH2PO4, each at -1.50 MPa, containing 0, 50, 100, or 150 mg.L-1 Pro-Ca. The priming treatments reduced thermodormancy and increased germination and emergence performances of lettuce seeds. The results indicated that inclusion of Pro-Ca into the priming solutions can be used as an effective method to overcome thermodormancy and improve germination and emergence performances of lettuce seeds at high temperatures.