干热胁迫下六种景天植物的形态特征及生理响应

以6种景天为试材,研究了45℃高温及干旱双重胁迫对其形态及生理变化的影响。结果表明:随着干热胁迫程度加重,6种景天植物叶片出现了萎蔫、发黄、卷曲、干枯脱落等症状,不同景天出现的先后和程度不同,反映了其耐干热性的差异。在整个胁迫过程中,土壤含水量持续下降;6种景天植物的叶片相对含水量及可溶性糖含量呈下降趋势;电导率和可溶性蛋白含量上升,不同景天上升幅度不同。综合形态特征及生理变化,耐干热性由强到弱的顺序是:八宝景天、黄花德景天、早花德景天、卧茎景天、红花德景天、红叶景天。

Study on Morphological Characteristics and Physiological Response Under Drought and Heat Stress in Six Sedum Plants

External morphology and physiological changes were studied under drought and 45℃ high temperature stress in six Sedum plants.The results showed that with serious level of drought and heat stress,leaves of six Sedum appeared dehydrate and curl,turned yellow,dried off and other symptoms.And different Sedum had different degrees at different stages.These expressions reflected their different tolerance to drought and heat stress.Throughout the stress process,soil moisture,relative water content and soluble sugar decreased.Conductivity and MDA contents increased,and different Sedum had distinct rate of increase.According to morphological characteristics and physiological changes,the resistance from highest to lowest to drought and heat in six plants was Sedum spectabile,Yellow S.hybridum’Immergrunchell’,Early S.hybridum’Immergrunchell’,Sedum sarmentosum Bunge,Red S.hybridum’Immergrunchell’,Sedum spurium ’Coccineum’.