果袋类型对黄冠梨褐斑病及Ca·Mg·K营养的影响

Effects of Fruit-bag Kinds on Browning Spot and Nutrition of Ca,Mg and K in Huangguan Pear

[目的]探讨套袋黄冠梨果实褐斑病的发生机制。[方法]于盛花后36 d对黄冠梨果实进行不同套袋处理;于果实成熟期(盛花后130 d)每株各选择一个基部主枝统计褐斑病发病率,并采取未套袋果实、套袋后表现正常、发病初期和发病后期的果实各30个进行果皮和果肉的Ca、Mg、K含量分析。[结果]套2层纸袋的果实中未发生果皮褐斑病,而套3层纸袋的果实中发生褐斑病。套袋降低了黄冠梨果皮中Ca含量和Ca/K比值,提高了K含量,特别是患病果实表现更为明显;但套袋对果肉中Ca、K含量影响较小。套袋均可提高果肉中Mg含量,降低果皮中叶绿素含量,但厚纸袋明显低于薄纸袋,患病果皮中叶绿素含量较低于正常果实。[结论]黄冠梨果皮褐斑病的发生与套厚袋诱导的果皮中低Ca含量和低Ca/K比值有密切关系。

[Objective] The aim was to explore the occurrence mechanism of browning spots in bagged Huangguan pear fruit. [Method] The fruit was bagged with different kinds of paper bags at 36 days after full bloom. The incidence rate of browning spots was accounted by choosing one basal leading branch at 130 days after full bloom,and Ca,Mg,K contents of pericarp and flesh of each treatment were analyzed. [Result] The results showed that no browning spots were observed in fruits covered with 2 layer paper bags,but the browning spots produced in fruits covered with triple layer paper bag. The bagging decreased Ca content and Ca/K of pericarp,but increased K content of pericarp,especially in the fruits showed serious browning spots. However,bagging slightly affected on the content of Ca and K in the flesh. The bagging enhanced Mg content of flesh and decreased chlorophyll content of pericarp,but which was more obvious in fruits covered with 3 layer paper bags. And meanwhile there were less content of chlorophyll in spot fruits than those normal ones. [Conclusion] The research suggested that the incidence rate of browning spot was closely related to the low Ca content and Ca/K of pericarp induced by bagging with 3 layer paper bags in Huangguan pear.