钾肥对直播密植枣园幼龄骏枣光合特性的影响

Effect of Potassium on Photosynthetic Characteristics of Young Jujube Trees in Close Planting Orchard

以新疆阿拉尔垦区典型的直播密植栽培模式下的骏枣为试材,研究钾肥施用量、施用时期以及施肥方式等对骏枣叶片叶绿素含量及光合特性的影响。结果表明,增施钾肥整体上提高骏枣叶片的叶绿素含量、净光合速率(Pn)和瞬时水分利用率(WUE),且以果实膨大期追施30kg/667m2和叶面肥喷施w=0.6%的钾肥处理效果较好。坐果期施钾肥显著提高WUE,但降低叶片蒸腾速率(Tr),其他参数指标差异不显著。说明施肥时期对骏枣叶片的光合特性影响较小。同时,骏枣叶片的叶绿素含量与其光合能力存在显著正相关。

Take typical pattern of close planting Junzao in Alar reclamation area of Xinjiang as experimental material, the influence of different fertilization periods and fertilization amount of potassium and fertilization methods on photosynthetic characteristics and chlorophyll content of Junzao leaf was studied. The results showed that potassium benefited the increase of the chlorophyll content, net photosynthesis rate （Pn） and plant water use efficiency （WUE）, the best result was obtained under the treatment of applying 30 kg/667 m2 potassium in fruit expansion period and 0.6% mass fraction of fotiar fertilizer. There was less effect on photosynthetic characteristics of iujube leaves in different fertilizing period except the fruit setting period while the transpiration rate （Tr） was decreased and WUE was increased significantly. Meanwhile, the chlorophyll contents of Junzao jujube leaves and photosynthetic capacity have a significant and positive correlation.