几种落叶果树H2O2含量变化与自然休眠关系的研究

 以设施栽培中常见的几种核果类果树品种和两个葡萄品种为试材, 分析了芽休眠期间 H₂O₂含量变化动态, 并探讨了温度、生长调节剂及化学破眠物质对H₂O₂含量影响的效应。结果表明: 休眠期间,不同树种( 品种) 芽内 H₂O₂含量存在差异, 基本趋势是晚熟品种高于早熟品种, 花芽高于叶芽, 但葡萄品种相反, 早熟的‘京秀’高于晚熟的‘巨峰’; 休眠期芽内 H₂O₂含量基本呈稳步上升后急剧下降的趋势,不同品种急剧下降的时间略有差别, 且与自然休眠解除的时间相吻合。低温(5 ℃) 处理显著增加了芽中 H₂O₂含量, 中温(10 ℃) 使 H₂O₂含量略有增加, 而高温(20 ℃) 却导致 H₂O₂含量降低。休眠前期50 mg.L^-1 ABA 处理显著提高了芽中H₂O₂含量, 而100 mg.L^-1的GA₃和6-BA 处理有减少 H₂O₂含量的趋势, 但二者差异不明显。热带地区常用的化学破眠物质对芽 H₂O₂的影响因树种( 品种) 、使用时期不同而异, 硫脲、KNO₃前期使用对核果类果树影响明显, CaCN₂对核果类无明显效应, 但对葡萄品种作用显著。果树芽 H₂O₂含量的动态变化表明, H₂O₂可能是低温解除自然休眠的原因。

The Relationship of H2O2 Content Changes in Buds with the Endodormancy of Fruit Trees

Changes of H₂O₂ content in buds associated with the endodormancy of some stone fruit tree and grape cultivars were studied. The results indicated that the H₂O₂ contents of dormancy buds were different due to different tree species and cult ivars. The trend was that H₂O₂ content of late􀀁maturing cultivars was higher than that of early maturing cultivars, and H₂O₂ content in flower bud was higher than that of vegetative bud; but grape cultivars were reverse. Dynamic state of H₂O₂ content in dormancy bud took on a trend of rising steadily in earlier stage and dropping quickly in later stage. The time which the H₂O₂ content dropped sharply was consistent with thet ime of endodormancy release. Temperature affected the dormant bud H₂O₂ content : low temperature (5 ℃) obviously raised the H2O2 content , middle temperature (10 ℃) only raised the H₂O₂ content slightly, but hightemperature (20 ℃) lead to the drop of the H₂O₂ content. Spraying regulators of ABA ( 50 mg.L^-1) obviously raised the H₂O₂ content of dormant bud, however, 100 mg.L^-1 GA₃ and 6-BA reduced the H₂O₂ content. Chemicals of dormancy release of thiourea and KNO₃ had obvious effects on H₂O₂ content of stone fruits, CaCN₂ had no effect on stone fruit trees but affected the H₂O₂ content of grape cultivars.