假单胞菌与褐藻寡糖协同提高梨果实产量及品质

Synergistic effects of Pseudomonas CD1 and brown algal oligosaccharides on pear fruit yield and quality

【目的】筛选梨树根际促生菌及与之具有协同增效作用的生物刺激素,探究其复配对梨果实产量和品质的影响,为开发复合型生物刺激素提供理论依据。【方法】根据菌株溶磷、解钾、固氮等特性,从128株供试梨树根际细菌中筛选对梨苗具有较强促生作用的菌株,同时从褐藻寡糖(AOS)、5-氨基乙酰丙酸(5-ALA)、γ-氨基丁酸(GABA)中筛选显著促进梨苗生长的生物刺激素,研究其与根际促生菌单用或复配对梨苗生长及梨果产量和品质的影响。【结果】筛选到具有显著促进梨苗生长的假单胞菌属菌株CD1和生物刺激素AOS。与清水对照(CK)、单接CD1和单施AOS相比,CD1与AOS复配可显著促进梨苗生长和侧根发生,梨苗生物量分别提高158.8%、59.0%和46.7%,根系长度分别增加33.7%、23.2%和26.3%。该复配液可显著促进梨果生长和提高产量,其中果实产量分别比CK、CD1和AOS处理提高73.7%、10.0%和14.8%,果实可溶性糖含量分别提高64.2%、29.0%和61.8%,石细胞含量分别比CK和AOS降低63.6%和43.1%,综合品质得到明显改善。与单施相比,复配处理使果实干重提高52.8%,果实氮、磷、钾、钙、镁、铜、锌和硼元素含量均不同程度增加,积累量显著提高。【结论】褐藻寡糖与假单胞菌CD1之间存在协同增效作用,其复配组合可实现梨果产量和品质同步提升。

【Objectives】Rhizosphere growth-promoting bacteria of pear trees and their associated biostimulants,which have synergistic effects with bacteria,were screened in our study to examine the combined effects of bacteria and biostimulants on the yield and quality of pear fruits.【Methods】Based on the characteristics of 128rhizosphere bacteria,including phosphate solubilization,potassium release,and nitrogen fixation,isolates with strong growth-promoting effects on pear seedlings were screened.Meanwhile,biostimulants that significantly enhance the growth of pear seedlings,such as alginate oligosaccharides(AOS),5-aminolevulinic acid(5-ALA),and gamma-aminobutyric acid(GABA),were also selected.The effects of bacteria alone or in combination with biostimulants on the growth of pear trees and the yield and quality of pear fruits were investigated.【Results】An isolate(Pseudomonas CD1) which significantly enhances the growth of pear trees,was identified.Additionally,AOS was identified as an efficient biostimulant.Compared to the control(CK),CD1 alone,and AOS alone,the combination of CD1 and AOS significantly enhanced the growth and lateral root initiation of pear seedlings,increasing biomass by 158.8%,59.0%,and 46.7%,respectively.The total root length increased by 33.7%,23.2%,and 26.3%,respectively,compared to CK,CD1 and AOS.Furthermore,this combination significantly promoted the growth and yield of pear fruits,increasing by 73.7%,10.0%,and 14.8%,respectively,and soluble sugar content increased by 64.2%,29.0%,and 61.8%,respectively,compared to CK,CD1,and AOS treatments.Meanwhile,the stone cell content in the combination treatment was significantly decreased by 63.6% and 43.1%compared to CK and AOS treatments,significantly improving fruit quality.The combination also increased fruit biomass by 52.8%.The N,P,K,Ca,Mg,Cu,Zn,and B mineral contents in the fruit were increased to varying degrees compared to CK,CD1 alone,and AOS alone,leading to a significant accumulation of mineral elements in the fruit.【Conclusions】AOS and Pseudomonas CD1 exhibited synergistic effects in promoting the yield and quality of pear fruits.However,their mechanism requires further study in the future.