Physiological Responses Of Lily Young Plants Under Heat Stress And Effects On Heat Resistance Of Plantlets From Radiated Scales

In this paper ,the heat tolerance of different lilium cultivar seedlings were studied on. The results obtained are summarized as follows:The seedlings of Asiatic hybrids 'Elite'were most sensitive to treament of 8h under 43℃,and also ,the ones of Oriental hybrids 'Casa Blanca'showed significant changes after 43 ℃ treated 72h. Young plants of the two cultivars wilt mostly and the leaves turn to yellow and thinner than CK.Leaf abaxial epidermis arranged more tightly and stomatal openning area were bigger than the ones of CK. After being treated with high temperature stress , the increasing range of membrance permeability, malondial dehyde(MDA) contents and Pro. contents of 'Elite' was greater than 'Casa Blanca' and the decreasing scope of POD activity of 'Elite' was greater than 'Casa Blanca',too. The amount of dead plants of 'Casa Blanca' was less than 'Elite' with 40℃ and 37℃ heat stress and recovered faster than the latter in room temperature .These indicated that the bulbs of 'Casa Blanca'seedling was more thermo-resistant than the ones of 'Elite', the changes of membrance , solub proteins, MDA contents , Pro. contents and POD activity can be used to indicated the heat tolerance of various cultivars in lilium seedling.After being treated by ~60Co gamma ray irradiation, different Ml plants had different variation as lower height , less blossom .Compared with cutting coefficient and variation of Ml plants, the resistance ability of the cultivars to irradiation were ranked from high to low as : longiflorum hybrids'White fox'>LA hybrids 'Ceb dazzle'>Oriental hybrids 'Marrero'. The contents of MDA, solub protein, Pro.and EC in leaves of 'White Fox'decreased after radiated by 2.0Gy, and the same to 'Marrero'and Ceb Dazzle' by 2.5Gy.dose irradiation.