Effects Of Microbial Agents On Rhizosphere Microorganisms Of Jujube Under Reduced Fertilizer Application Conditions

Jujube,belonging to the genus Rhamnaceae.It is rich in nutrients and contains a lot of vitamin C,which ranks among the top fruits.As a crop growing in temperate zone,jujube has strong ability to adapt to the environment and has a wide range of planting.Due to the unique natural geographical conditions of drought,lack of rain and sunshine in Xinjiang,jujube have become one of the characteristic fruits of Xinjiang.The jujube planting in Xinjiang has been obtained.A large area of development,Xinjiang's red jujube planting areas are mainly Aksu,Kashgar,Hetian and other regions.Due to the low content of organic matter in Xinjiang soil,and the extensive management of jujube garden,the amount of fertilization is large and its utilization rate is low,which affects the yield,quality and economic benefits of jujube.At present,some red jujube growers use blindly to increase production because of lack of professional technical support.They use a large amount of chemical fertilizers during the jujube planting process,and do not pay attention to the absorption and utilization of trace elements by jujube trees,which not only leads to the imbalance of jujube nutrition.The large application of chemical fertilizers also has a very serious negative impact on the soil(the effective utilization rate of fertilizers and the effect of increasing yield,the soil fertility decline,affecting the ecological environment in the soil,etc.).Therefore,the development of green agriculture,organic agriculture,ecological agriculture,to a certain extent reduce the amount of fertilizers and pesticides,to avoid aggravating environmental pollution is the goal of future agricultural development.This paper,the effects of microbial agents on the rhizosphere microorganisms of jujube were studied by detecting the colonization of B.subtilis NCD-2 and B.amylolique faciens and the field experiment.The results are as follows:(1)Both strains NCD-2 and S13 can be successfully colonized in jujube seedlings and rhizosphere soil.The marker strain NCD-2~~R was detected in the roots,stems and leaves of jujube seedlings on the third day after inoculation,and the colonization amount was the largest at 1.49×10~~3cfu/g,7.5×10~~3cfu/g,1×10~~3cfu/g,the colonization gradually decreased with time;while the NCD-2~~R in the soil was separated from the first day,and the colonization reached a maximum at2.5×10~~6cfu/g on the third day.The marker strain S13~~R was detected in the roots and leaves of jujube on the third day after inoculation.At this time,the colonization amount of the strain reached the maximum,which was 3.5×10~~2cfu/g and0.45×10~~2cfu/g,respectively,and The colonization of S13~~R in jujube stems reached the maximum on the 7th day,which was 0.5×10~~2cfu/g;the colonization of S13~~R in the soil reached the maximum on the first day of inoculation,which was 7.5×10~~4cfu/g.After that,the colonization gradually decreases with time.(2)The combination of NCD-2 and S13 with bio-organic fertilizer can increase the number of micro-organisms in the rhizosphere soil of jujube,and its effect on the quantity of various microorganisms in the jujube,expansion and maturity of jujube the same.Compared with CK(no fertilization),NCD-2 and S13 combined with organic fertilizer can increase the content of bacteria and fungi in the rhizosphere soil of jujube.The bacterial content in the rhizosphere soil of NCD-2 combined with organic fertilizer is The jujube fruit was the highest at the young fruit stage,which was 1.3×10~~6cfu/ml.The fungi content in the soil with S13 and organic fertilizer reached the maximum at the ripening stage of red jujube,which was 3.6×10~~5cfu/ml.In the young fruit stage,the rhizosphere soil was placed.n the young fruit period of jujube,the relationship between the content of actinomycetes in rhizosphere soil is:NCD-2 combined with organic fertilizer is greater than CK is greater than S13combined with organic fertilizer;in the red jujube expansion period,the size relationship is:S13 The organic fertilizer was larger than NCD-2 and the organic fertilizer was higher than CK.However,in the mature stage of red jujube,the relationship between actinomycetes in rhizosphere soil was:S13 combined with organic fertilizer was greater than CK and NCD-2 was combined with organic fertilizer.(3)The combination of NCD-2 and S13 with bio-organic fertilizer can increase the microbial metabolic activity of jujube soil,promote the change of carbon source utilization,and enrich the functional diversity of rhizosphere soil microbial community.Compared with the control,the treatment of NCD-2 and organic fertilizer and S13 and organic fertilizer increased the AWCD value of rhizosphere soil at the young and mature stage of red jujube,but had no effect on the AWCD value during the expansion period,and NCD-2 and S13 combined with organic fertilizer to improve the ability of AWCD in different time periods.Soil microbes with NCD-2 and organic manure showed relatively high utilization of carbohydrates in the young fruit stage of the jujube,expansion and maturity,while the soil microbes with S13 and organic fertilizer were in the whole growth period of the red jujube.The utilization of amines is relatively high.NCD-2and S13 combined with bio-organic fertilizer can increase the Simpson index,Shannon index and McIntosh index during the whole growth period of red dates.(4)The study on the yield and quality of jujube with organic fertilizer combined with organic fertilizer showed that NCD-2 and S13 combined with bio-organic fertilizer could promote the fruit-bearing rate of jujube,and could increase the average fruit weight and yield of jujube.The application of organic fertilizer with organic fertilizer can reduce the total acid content in red dates,increase the soluble solids and reducing sugar content of red dates,and increase the content of vitamin C in jujube.