解磷菌与秸秆配施对低磷胁迫下苦荞幼苗生长发育的影响

Effects of Combined Application of Phosphate-Solubilizing Bacteria with Straw Application on Growth and Development of Tartary Buckwheat Seedlings under Low Phosphorus Stress

为明确花域芽孢杆菌gz4-1与秸秆配施对苦荞幼苗生长发育的影响,于2019年以‘迪庆’苦荞为材料,设置秸秆[0 g·kg^(-1)土壤(J0)、4 g·kg^(-1)土壤(J1)]和菌液浓度[0 (P0)、10^(4)(P1)、10^(6)(P2)、10^(8)(P3)、10^(10)(P4) cfu·mL^(-1)]两因素复合处理,以正常施肥为对照(CK),采用盆栽试验探究花域芽孢杆菌gz4-1与秸秆配施对苦荞幼苗根系、地上部形态和生理特性的影响。结果表明:(1)花域芽孢杆菌gz4-1与秸秆配施促进苦荞根系鲜质量、干质量、主根长、根系表面积和根冠比,幼苗主根长在J0P2处理下最高,比CK显著提高12.1%,根系表面积和根冠比均在J1P1处理下最高,分别比CK显著提高115.6%和103.3%。(2)花域芽孢杆菌gz4-1与秸秆配施促进苦荞幼苗茎粗、株高、鲜质量、干质量和节数的生长,幼苗株高和节数在J1P3处理下最高,分别比CK提高43.6%和33.3%。(3)随着菌液浓度的增加,苦荞幼苗根系活力和根系P含量均先升后降且在P2浓度下最高,在低磷胁迫(J0)条件下,根系酸性磷酸酶活性降低,在施加秸秆(J1)条件下,酸性磷酸酶活性在P2浓度时达到峰值。说明花域芽孢杆菌gz4-1与秸秆配施可通过改变苦荞幼苗形态和根系构型、提高根系活力,改善根系生理机能提高对苦荞幼苗生长发育的影响,且综合因素考虑在10^(6) cfu·mL^(-1)(P2)菌液浓度下配施秸秆对苦荞幼苗的促生作用最大,可达最佳促生增产效果。

In order to understand the effect of combined application of Bacillus Floridans gz4-1 and straw on the growth and development of tartary buckwheat seedlings,taking ‘Diqing’ tartary buckwheat as material in 2019,using normal fertilization as control(CK),two factors combined treatment of straw [0 g·kg^(-1) soil(J0),4 g·kg^(-1) soil(J1)] and bacterial liquid concentration [0(P0),10^(4)(P1),10^(6)(P2),10^(8)(P3),10^(10)(P4)cfu·mL^(-1)] were set in this paper.A pot experiment was conducted to investigate the effects of combined application of Bacillus Floridans gz4-1 and straw on root and shoot morphology and physiological characteristics of tartary buckwheat seedlings.The results showed that:(1) The combined application of Bacillus Floridans gz4-1 and straw promoted the root surface area and root shoot ratio of tartaric buckwheat root fresh mass,dry mass,taproot length and root shoot ratio.The taproot length of seedlings was the highest under J0 P2 treatment,which significantly increased by 12.1% compared with CK.The root surface area and root shoot ratio were both the highest under J1 P1 treatment,which significantly increased by 115.6% and 103.3% compared with CK.(2) The combined application of Bacillus Floridans gz4-1 and straw promoted the stem diameter,plant height,fresh mass,dry mass and node number of tartary buckwheat seedlings,the plant height and node number were the highest under the treatment of J1 P3,which were 43.6% and 33.3% higher than CK.(3) With the increase of bacterial solution concentration,root activity and root P content of tartary buckwheat seedlings increased firstly and then decreased,and reached the highest value under P2 concentration.Under low phosphorus cultivation(J0) condition,root acid phosphatase activity decreased,and under condition of straw returning to field(J1),root acid phosphatase activity reached the peak value under P2 concentration.That Bacillus Floridans gz4-1 and straw could improve root activity,root physiological function by changing the buckwheat seedling morphology and root architecture,finally,its effect on the buckwheat seedling growth was improved.Comprehensively,under treatment of 10^(6) cfu·mL^(-1)(P2) bacteria liquid concentrations,combined application of straw had the greatest growth-promoting effect on tartary buckwheat seedlings.