2种内生细菌对文冠果幼苗矿质元素吸收的影响

Effects of two endophytic bacteria on mineral elements uptake of xanthoceras sorbifolia seedlings

为探究前期筛选的具有溶磷、产铁载体、产IAA能力的内生细菌对文冠果(Xanthoceras sorbifolia Bunge)幼苗矿质元素的影响,选取一株假单胞菌属菌株XSB5和一株约克氏菌属菌株GG10作为试验菌株。用菌液浸泡经过层积催芽的文冠果种子,待植株长出第一片真叶后,用等量的菌液和清水处理文冠果幼苗,4个月后分析文冠果植株的生长状况。结果表明:用XSB5菌液处理后,文冠果植株地上和地下生物量均显著增加(P<0.05);GG10菌液处理后,文冠果地上和地下生物量均有所增加,地下生物量增加达显著水平(P<0.05);两种菌液处理后文冠果植株N、P、Mg积累量较对照显著增加(P<0.05),Fe积累量因处理时间不同而有差异;4种矿质元素的转运系数因不同菌液、不同处理时间而有差异;栽培基质中有效态N、P含量较对照显著增加(XSB5-30处理除外),有效态Mg、Fe含量与对照无显著差异。说明接种这2种内生细菌能影响栽培基质中矿质元素含量的变化,提高文冠果植株对矿质元素的吸收,改变矿质元素向上的运输能力,从而促进文冠果植株的生长。该研究可为文冠果促生菌肥的筛选提供一定的理论基础。

We used Pseudomonas sp. XSB5 and Yorkella sp. GG10 as the test strains to explore the effects of endophytic bacteria with the ability of phosphorus solubilization and production of siderophore and IAA on nutrient uptake of Xanthoceras sorbifolia Bunge seedlings. The seeds of X. sorbifolia were immersed in the bacterial solution. After the first euphylla grew,X. sorbifolia seedlings were treated with the same amount of bacterial solution or water,and the growth of X.sorbifolia was analyzed four months later. The results showed that root and aerial part dry weights of X. sorbifolia were significantly increased after treated with XSB5 bacterial solution. After treated with GG10 bacterial solution,root and aerial part dry weights of X. sorbifolia were increased,and the root part dry weights increased significantly. The accumulation of nitrogen,phosphorus,and magnesium in X. sorbifolia was significantly enhanced,and the accumulation of iron varied with the treatment duration. The translocation factors of those four mineral elements were different depending on the treatment duration of different bacterial solutions. The available nitrogen and phosphorus contents in the culture substrate were significantly increased(except XSB5-30 treatment),and the available magnesium and iron contents were not significantly different compared to the control. Our results indicated that the inoculation of two endophytic bacteria could affect mineral elements in the culture substrate,increase the uptake of mineral elements by X. sorbifolia,change the transport capacity of mineral elements upwards,and promote the growth of X. sor-bifolia. This study provides substaintial basis for the screening of the growth-promoting bacterial fertilizer.