两株球形赖氨酸芽孢杆菌对巨桉幼苗生长及光合特性的影响

Effects of two strains of Lysinibacillus sphaericus on growth and photosynthetic characteristics of Eucalyptus grandis seedlings

为了解两株具有较好溶磷效果的球形赖氨酸芽孢杆菌(YP17和P19)对巨桉幼苗生长及光合特性的影响,通过盆栽试验分别测定单菌、混菌及与有机肥配施等不同处理下的巨桉幼苗株高、地径生物量、根冠比、净光合速率(Pn)和叶绿素含量.结果表明:与空白对照(CK)相比,除单独接种YP17处理的叶绿素含量略低于CK外,其它施菌处理均可显著促进巨桉幼苗生长,并提高净光合速率和叶绿素含量,其中,植株株高、地径、生物量、Pn、叶绿素含量较CK增长了6.5%-65.9%、18.2%-75.1%、6.3%-174.7%、57.1%-123.5%、14.7%-196.5%;单独接种P19会降低幼苗根冠比,而单独接种YP17则会促进幼苗根系生长;两株菌单施效果均显著优于混施;与施有机肥对照比较,P19与有机肥的共施效果优于单施有机肥,YP17与有机肥的共施效果劣于单施有机肥,但其效果均较单菌处理差.本研究表明,YP17和P19在促进巨桉幼苗生长方面具有较高潜力,且P19的接种效果优于YP17.

This paper aimed to explore the effects of two strains of Lysinibacillus sphaericus with good phosphate-solubilizing effect（YP17 and P19） on the growth and photosynthetic characteristics of Eucalyptus grandis seedlings.We measured the plant height,ground diameter,biomass,root-shoot ratio,net photosynthetic rate（Pn） and chlorophyll content of E.grandis seedlings with different combined treatments of single bacteria,mixed bacteria,and organic fertilizer in pot experiment.Except for the reduced plant chlorophyll content by the treatment of YP17,all treatments significantly promoted the growth and net photosynthetic rate of E.grandis seedlings compared to blank control（CK）.Plant height increased in the range of 6.5% – 65.9%;ground diameter increased by 18.2% – 75.1%;biomass increased in the range of 6.3% – 174.7%;Pn increased in the range of 57.1% – 123.5% and chlorophyll content by 14.7% – 196.5%.Inoculation of P19 reduced the root-shoot ratio of seedlings,but that of YP17 enhanced the growth of root system.The effect of the two strains was significantly better when administered separately than in mixed application.The mixed application of P19 and organic fertilizer had a better effect t han single application of organic fertilizer,which was in turn better than the mixed application of YP17 and organic fertilizer.Both strains had better effects when applied alone than mixed with organic fertilizer.As a conclusion,YP17 and P19 both have great potential in promoting E.grandis seedlings growth,with the strain P19 more effective than YP17.