Study On Key Technology Of Healthy Tobacco Plant And The Improvement Of Tobacco Field Environment

Tobacco is an important economic crop, occupies an important position in the national economy.Production of quality tobacco requires a robust tobacco seedlings and good tobacco fields ofenvironmental conditions. Today’s tobacco-growing existence of phenomenon of long-term continuouscropping and fertilizer, pesticides, heavy use, etc, caused by the imbalance of soil nutrients, soilcompaction, soil contamination, soil bacteria accumulation. These issues will cause the decline oftobacco production and tobacco lower quality. Liangshan locates in the southwest of Sichuan Province,it is one of the most suitable area for producing high quality flue-cured tobacco,the produced tobaccohas win the good graces by the cigarette industry. But Liangshan is a typical mountain agriculture,stereoscopic weather significantly, there are some problems in the flue-cured tobacco production.Suchas tobacco seedling stress resistance difference; drought in the earlier stage of tobacco growth and rainyin last period; low temperature in the earlier stage of tobacco growth and high temperature in middlestage. In this article, for the main problems in Liangshan, in2011, the seedling and field experimentswere carried out at experimental farm in the centre of technique popularize and application, inLiangshan Tobacco Corp. Ltd. by seedling tests and field trials, carried out the study by chemicalcontrol measures to cultivate robust disease-free tobacco seedlings, the study of the different coveragepatterns of wide double ridge, the study of the different intercropping patterns of wide double ridge. Themain research results are as follows:(1) Chemical control measures is feasible to cultivate flue-cured tobacco strong seedlings. Thisstudy shows that for floating nursery to cultivate robust disease-free tobacco seedlings, in differentstages of seedling growth, by spraying of controlled substances, promoting the growth at the beginningand controlling it towards the end,promoted the root growth of seedling, the root, stem and leaf oftobacco seedlings growth coordination, aboveground and belowground material allocation is reasonable;by chemical control measures the developed root system was formed, strong root vigor, highchlorophyll content, promote the absorption and utilization of mineral elements in tobacco seedlings;after spraying of controlled substances the resilience indicators of high quality of tobacco seedlings,ability to withstand adverse environmental enhanced, pests and diseases significantly reduced.Comprehensively, sprayed with3–indole butyric acid (0.010g/L) in3leaf stage, sprayed withpaclobutrazol (0.003g/L) in7leaf stage; sprayed with rooting powder (0.010g/L) in3leaf stage,sprayed with paclobutrazol (0.003g/L) in7leaf stage; sprayed with naphthylacetic acid (0.010g/L) in3leaf stage, sprayed with ethephon (0.010g/L)in7leaf stage had the best effect.(2)The different coverage patterns of wide double ridge had different effects of soil physical andchemical properties, microclimate in tobacco fields and the growth and developmental of flue-curedtobacco, which dual mulch and straw mulch the effect of regulate tobacco fields soil physical andchemical properties and field microclimate was most obvious, conducive to the cultivation of healthyflue-cured tobacco.Dual mulch, polythene mulch and straw mulch can improve soil water retention capacity, reduce soil bulk density, increase the content of soil organic matter, available nitrogen, available potassium andavailable phosphorus. Dual mulch and straw mulch can play a role in thermal insulation during the earlygrowth stage of flue-cured tobacco, play a role in cooling during the medium-term, and dual mulch thepre-insulation effect is better, dual mulch and straw mulch had smooth change of soil temperature in theday, conducive to the growth of flue-cured tobacco root. In the tobacco plant at20cm and50cm, thedifference of day-night temperature was most of dual mulch, conducive to the flue-cured tobacco,especially the accumulation of inclusions in the middle leaves, this is beneficial for the improvement ofthe quality of tobacco leaves; at the100cm, has little difference of day-night temperature. Dual mulchis conducive to the improvement of the chlorophyll content, can enhance the performance of thephotosynthetic, conducive to growth and development of flue-cured tobacco, the dry matteraccumulation, tobacco grow healthy and accordant, strong disease resistance, low incidence of fieldcommon diseases.Dual mulch can significantly improve roasted tobacco on the medium tobacco ratio and theaverage price, yield and value were the highest, had the best economic benefits. Dual mulch and strawmulch can significant increase in baked tobacco reducing sugars, total sugar and potassium content,reduce the total alkali content of tobacco, coordinated the derived value of sugar alkali, sugar, nitrogen,potassium, chlorine, nitrogen base ratio of the tobacco leaf, improve the intrinsic quality of the tobacco.(3) The different intercropping patterns of wide double ridge had different effects of soil physicaland chemical properties, and the growth and developmental of flue-cured tobacco, which flue-curedtobacco and onion intercropping the effect of regulate tobacco fields environment and conducive toflue-cured tobacco robust growth was most obvious.Flue-cured tobacco intercropping pattern can increase the content of soil organic matter, availablenitrogen, available potassium and available phosphorus, reduce soil bulk density, improves soil physicaland chemical character. Study found that the flue-cured tobacco intercropping pattern to coordinate soilmicrobe environment, increase the number of beneficial bacteria, and inhibit pathogenic bacteria,effectively reduce the incidence of the disease of flue-cured tobacco field. The different intercroppingpatterns improved the production of tobacco on the medium tobacco ratio and the average price, whichthe effect of flue-cured tobacco and onion intercropping patterns are most obvious.The different intercropping patterns increase in baked tobacco reducing sugar, total sugar content,intercropping of flue-cured tobacco and legume crops will increase tobacco total alkaloids and totalnitrogen content, the flue-cured tobacco and onion intercropping model significant increase in thepotassium content, coordinated the derived value of the alkali than sugar, sugar, nitrogen, potassiumchlorine, nitrogen base ratio, conducive to the internal improvement of the quality of tobacco.