The Effect Of Bracket Plastic Mulching For Single-plant On The Soil Microorganisms Of Tobacco

The cultivation of farmland mulch influences soil temperature,humidity and illumination,which leads to the physical and chemical properties of soil,rhizosphere and non-rhizosphere microorganism quantity and soil enzyme activity changed.In order to explore the effect of the new invention bracket plastic mulching for single tobacco plant on soil microorganisms,we conducted field experiments in planting base of Guiyang County,Hunan Province in 2015 ~ 2016.The experiment included three treatments: bracket plastic mulching for single plant,ordinary plastic mulching and without mulching.The experiment was set up three different transplanting periods,seven time sampling and 756 soil samples.The cloning numbers of soil bacteria,actinomycetes and fungi were tested by dilution plate counting method;The BIOLOG ECO method was used to study the microbial community structure of 72 rhizosphere soil samples.The effect of single plant mulch on urease activity,sucrase activity,alkaline phosphatase activity,catalase activity in tobacco field was studied by using the method of colorimetry,3,5-dinitrosalicylic acid colorimetry,disodium phenyl phosphate colorimetry,potassium permanganate titration.Main results are as follows: 1.The effect of bracket plastic mulching for single-plant on the rhizosphere and non-rhizosphere microorganisms of tobaccoThe cloning numbers of soil bacteria,actinomycetes and fungi were tested by dilution plate counting method.The results showed that the cloning numbers of soil bacteria in rhizosphere soils with different treatments have changed at different sampling times after transplanting.The total cloning numbers of rhizosphere bacteria were significantly different between the three treatments(p<0.05),the cloning numbers of bracket plastic mulching for single plant treatment were the highest,ordinary mulching treatment ranged the second and without mulching treatment were the least.The total cloning numbers of actinomycetes in the rhizosphere soil treated by bracket plastic mulching for single plant were significantly higher than those of without mulching treatment,which reached a significant difference level(p<0.05);and they were also higher than those of ordinary plastic mulching,the difference reached significant in 2016(p<0.05).The total cloning numbers of rhizosphere fungi in both bracket plastic mulching for single plant and ordinary plastic mulching were significant higher than those without mulching treatment(p<0.05).And the fungal cloning numbers reached the significant level(p<0.05)between bracket plastic mulching for single plant and ordinary plastic mulching treatments.2.The effect of bracket plastic mulching for single-plant on the microbial community metabolish of tobaccoThe BIOLOG ECO method was used to study the microbial community structure of rhizosphere soil samples.The results showed that with the increase of the culture time of microorganisms,three kinds of treatment of the average optical density AWCD gradually increased and the metabolic activity increased.In the three treatment,the tobacco soil microorganism treated by the bracket plastic mulching for single-plant was the highest utilization of carbon source,ordinary mulching treatment ranged the second and without mulching treatment were the least.Amino acids and their derivatives are the main source of carbon for various coating methods.3.The effect of bracket plastic mulching for single-plant on the soil enzyme activities of tobaccoThe effect of single plant mulch on urease activity,sucrase activity,alkaline phosphatase activity?catalase activity in tobacco field were studied by using the method of colorimetry,3,5-dinitrosalicylic acid colorimetry?disodium phenyl phosphate colorimetry?potassium permanganate titration.The results showed that the activity of urease,sucrase,catalase and alkaline phosphatase in tobacco soil showed that the activities of sucrase and alkaline phosphatase were less affected by the coating.There was no significant difference in soil enzyme activities among the three treatments,which reflected to a certain extent the small changes in soil organic carbon and phosphorus.There was no significant difference in catalase activity in the three non-rhizosphere soils treated with plastic film.