Effects Of Planting Density And Remained Leaves Number On Physio-biochemical Characteristics Of Tobacco In Pengshui Mountainous Region

In the process of flue-cured tobacco production, cultivation measures are one of the important factors in affecting the growth and development, final yield and quality and the chemical quality of tobacco plants. In order to study the growth and development regularity, plant type characteristics, yield and quality and chemical quality and related enzyme activity of flue-cured tobacco under different cultivation measures. We use YunYan-97to do the related research in Chongqing Pengshui in2012. Agronomic characters, plant type, yield and quality, chemical quality, key enzymes of carbon and nitrogen metabolism and membrane protective enzyme and other enzymes of the different planting density and remained leaves number were observed records, testing and statistical analysis.The main results are as follows:1.The influence of different planting density and remained leaves number on biological traits and plant type of flue-cured tobacco. With the development of growth period, the plant height, stem circumference, maximum leaf length and leaf width, leaf area of flue-cured tobacco were increasing trend. Plant height increased with the increase of planting density and remained leaves number. Stem circumference, maximum leaf length and leaf width and leaf area were decreased with the increase of planting density. However stem circumference increased with the increase of the remained leaves number. Under the three remained leaves number treatment, maximum leaf length change was not obvious. Maximum leaf width was decrease with the increase of remained leaves number. Under the three remained leaves number, leaf area show as18＞22＞14. The plant type of planting density1100 and1300and remained leaves number18and22were drum-shaped. Taken together, the performance of planting density1100and remained leaves number22was best in the agronomic traits and plant type.2.The influence of different planting density and remained leaves number on yield and quality of flue-cured tobacco. Unit area yield increased with the increase of the planting density. Under the three planting density, unit area value, proportion of the superior tobacco and proportion of the superior and secondary tobacco show as1100>1300>900. Unit area yield, unit area value, proportion of the superior tobacco and proportion of the superior and secondary tobacco of flue-cured tobacco were increasing trend, which suggests that increasing planting density and remained leaves number can improve the yield and quality of tobacco plant. Taken together, the performance of planting density1100and remained leaves number22was best in the unit area yield, unit area value and proportion of the superior and secondary tobacco.3.The influence of different planting density and remained leaves number on chemical quality of flue-cured tobacco. The reducing sugar content, nicotine content, potassium content, radio of sugar and nicotine and radio of potassium and chlorine of tobacco of planting density1100are appropriate. The reducing sugar content, nicotine content, nitrogen content, potassium content, radio of sugar and nicotine, radio of nitrogen and nicotine and radio of potassium and chlorine of tobacco of planting density1100are appropriate. The reducing sugar content, nicotine content, nitrogen content, potassium content, radio of sugar and nicotine, radio of nitrogen and nicotine and radio of potassium and chlorine of tobacco of remained leaves number18are appropriate. The reducing sugar content, nicotine content, nitrogen content, radio of nitrogen and nicotine of tobacco of remained leaves number22are appropriate. In combination with chemical composition and coordination evaluation score, we can see that tobacco of planting density1100and remained leaves number22is the best in chemical quality and it composition is the best coordination.4.The influence of different planting density and remained leaves number on carbon metabolism of flue-cured tobacco. Total sugar content and sucrose phosphate synthase activity increased with the increase of planting density and remained leaves number. The activity of sucrose synthase increased with the increase of planting density. Under the three planting density, amylase activity show as1100>1300>900. Under the three remained leaves number, amylase activity and sucrose synthase activity show as18>22>14. 5.The influence of different planting density and remained leaves number on nitrogen metabolism of flue-cured tobacco. Under the three planting density, protein content show as1100＞900＞1300, nitrate reductase activity and glutamine synthesis activity show as1300＞900＞1100. Under the three remained leaves number, protein content show as18＞22＞14, nitrate reductase activity show as14>22>18, glutamine synthesis activity show as18＞14＞22.6.The influence of different planting density and remained leaves number on membrane protective enzyme and other enzymes activity of flue-cured tobacco. Phenylalanine ammonialyase activity and polyphenol oxidase activity decreased with the increase of planting density. Peroxidase activity and catalase activity increased with the increase of planting density. Under the three planting density, superoxide dismutase activity show as1100＞900＞1300. Under the three remained leaves number, phenylalanine ammonialyase activity show as18＞14＞22, peroxidase activity show as18＞22＞14, superoxide dismutase activity and catalase activity decreased with the increase of remained leaves number, polyphenol oxidase activity increased with increase of remained leaves number.