钙和硅叶面肥对‘黄冠’梨果实发育期间生理生化变化的影响

Effect of foliar calcium and silicon fertilizers on the physiological and biochemical changes in‘Huangguan'pear fruit during the fruit development

[目的]探究钙、硅叶面肥对‘黄冠’梨果实发育过程中果实抗性的影响,为缓减‘黄冠’梨果面褐斑病的发生提供理论依据。[方法]以盆栽4年生‘黄冠’梨为试材,在幼果期和膨大期分别喷施钙肥、硅肥及其配施,研究其对果实发育期间生理生化变化的影响,并调查田间12年生‘黄冠’梨成熟期果实品质及褐斑病发病率受此施肥方式的影响。[结果]随着果实的生长发育,钙、硅配施处理膨大期(花后100 d)果肉细胞壁水解酶活性显著低于对照,成熟期(花后125 d)多聚半乳糖醛酸酶(PG)和纤维素酶(Cx)活性分别比对照低25.3%和50.1%;果肉中原果胶(PP)含量在果实膨大期和成熟期分别比对照高41.4%和40.7%,而可溶性果胶(SP)含量在膨大期比对照显著低60.7%,这有利于提高膨大期和成熟期果肉细胞壁的稳定性。钙、硅配施显著提高了膨大期和成熟期果肉中活性氧清除酶活性,成熟期超氧化物歧化酶(SOD)和过氧化物酶(POD)活性分别比对照高244.8%和188.9%,而丙二醛(MDA)含量显著降低91.1%,这会降低成熟期果肉中活性氧伤害,抑制膜脂过氧化。此外,钙、硅配施显著降低了田间果面褐斑病发生率,较对照降低49.4%。[结论]钙、硅配施能增强膨大期和成熟期果实抗性,有效降低果面褐斑病发生率。

[Objectives]This study aimed at evaluating the effects of foliar calcium and silicon fertilizers on the fruit resistance ability of‘Huangguan＇pear during its growth,so that it could provide more theoretical basis for reducing incidence of brown spot disease.[Methods]Treatments were set as follows： separately spraying chelated calcium（ SC） and silicon fertilizer（ SS） and cooperatively spraying both calcium and silicon（ SCS） on the 4-year-old potted‘Huangguan＇pear at fruit stages of young and expansion,and the changes of physiological and biochemical indexes during fruit growth in all treatments were observed. At the same time,we also investigated the fruit quality and the brown spot disorder in field experiments which had used the same fertilizers to make sure whether this kind of fertilizing method could do some effects on the 12-year-old pear trees in fields. [Results]With the fruit development in the pot experiments,SCS significantly inhibited the activities of wall-metabolic hydrolases such as polygalacturonase（ PG） and cellulases（ Cx） in fruit pulp at the stage of expansion（ that is,on 100 days after full bloom）,resulting in their activities at maturity（ that is,on 125 days after full bloom） 25. 3% and 50. 1% lower than control respectively. Moreover,the protopectin（ PP） contents at the stages of fruit expansion and maturity under this treatment were significantly increased by 41. 4% and 40. 7%,while the soluble pectin（ SP） at the expansion stage had decreased 60.7% in contrast to control,which indicated that SCS could more effectively maintain the stability of cell wall. In addition,the activities of superoxide dismutase（ SOD） and peroxidase（ POD）,who belonged to the active oxygen eliminating enzymes,at both stages of expansion and maturity were remarkably raised by SCS. At maturity,each of them comparatively increased 244.8% and 188.9% along with a 91.1% lower malondialdehyde（ MDA） content in this treatment. These results suggested that SCS was an effective way to control the incidence of brown spot disorder,at the same time it could also enhance the resistance to the lipid peroxidation caused by the invasion of reactive oxygen species in pear fruit. Besides,it was found that SCS could significantly inhibit brown spot disorder in the field experiments,which led to a 49.4% decrease compared to the control. [Conclusions]SCS could enhance the fruit resistance at both stages of expansion and maturity,which made contributions to the lower incidence of brown spot disease.