花期和幼果期低温对玉露蟠桃花果器官的影响

目的]研究低温对蟠桃花粉活力、雌蕊受冻率和幼果受冻率的影响。方法]在低温培养箱中对玉露蟠桃和锦绣黄桃离体带花朵枝条进行不同温度和不同时间的低温处理并测定相关指标。结果]低温处理降低了2个品种桃花药的花粉量和花粉萌发率,但是对花粉管长度的影响不显著,2个品种间差异不显著;玉露蟠桃柱头较锦绣黄桃柱头抗冻;玉露蟠桃的幼果较锦绣黄桃品种不抗冻害,-2℃处理2 h与-4℃处理1 h后玉露蟠桃的受冻率达40.91%与48.94%(锦绣黄桃受冻率为7.69%和21.05%)。结论]初步分析认为玉露蟠桃较锦绣黄桃品种坐果率低的主要原因是幼果受到低温的影响比较大,因此幼果期需要做好抗霜冻低温的防御工作,花期与幼果期温度不能低于-4℃。

Effects of Low Temperature Stress in Florescence and Young Fruiting Period on Flowers and Fruits Organ of Yulu Flat Peach

Objective] To study the effects of low temperature stress on the pollen viability,pistil frostbite rate and young fruit frostbite rate of flat peach.Method]The branches with flowers of Yulu flat peach and Jinxiu yellow peach cultivars were treated with different temperature and time duration in low temperature incubator,and then the relevant indexes were investigated.Result] Low temperature treatment reduced the pollen amount and pollen germination with small variance among cultivars,but it didn't affect the pollen tube length.The pistil damage of Yulu flat peach was less affected by chilling treatment than the Jinxiu yellow peach.The young fruit frostbite rate of Yulu flat peach were 40.91％ and 48.94％ at-2 ℃ treating for 2 h and-4 ℃ treating for 1 h and more serious than Jinxiu yellow peach which the young fruit frostbite rate were 7.69％ and 21.05％,respectively.Conclusion] The main reason of low fruit setting of Yulu flat peach under chilling stress is the young fruits are more sensitive,so good defense against frost and cold need to be done in young fruit period.The temperature cannot be lower than-4 ℃ in the florescence and young fruiting period.