The Effect Of Water-Permeability Plastic Film On Water Seepage,Drought Resistance,Yield And Quality Of Tobacco

Plastic film mulching is an important cultivation measure in the process of tobacco planting.Although ordinary plastic film mulching technology can keep water and heat,it can not effectively use the water resources of natural rainfall.Water-permeability plastic film is a new type of plastic film widely used in arid and semi-arid areas in recent years.It not only has the functions of heat preservation and humidification,but also has the advantages of water seepage and micro ventilation,which can effectively improve the utilization efficiency of small rainfall water resources and increase crop yield.Shandong is a semi humid area,but the annual distribution of precipitation is uneven.Before the rainy season,the rainfall is mainly sporadic small rainfall.How to make full use of rainwater resources during this period is the key factor to promote the high-quality development of tobacco in Shandong Province.In this research,NC102 was used as the experimental material,and ordinary plastic film was used as the control,the effect of water permeable plastic film and ordinary plastic film on soil moisture content,basic physical and chemical properties,agronomic traits of tobacco plants,tobacco yield and chemical composition of cured tobacco leaves were measured in outdoor field.The effect of water-permeability plastic film on water retention and drought resistance,growth,yield and quality of tobacco were studied.The results are as follows:(1)Water-permeability plastic film significantly improved the soil water and heat condition.After transplanting tobacco leaves in the field,there is no artificial irrigation.The rainwater infiltration effect of water-permeability plastic film was determined by measuring the moisture content of different soil depths.The results showed that the water content of 10 cm,20 cm and 30 cm soil layers was 79.90%,23.87% and 10.76% higher than that of traditional plastic film,respectively.At the same time,the water retention effect of water-permeability plastic film was studied indoor,and the results showed that there was no significant difference between the water retention effect of water-permeability plastic film and ordinary plastic film.In the aspect of maintaining soil temperature,water-permeability plastic film significantly increased the soil temperature of 0～15cm soil layer,but the effect of increasing soil temperature gradually weakened with the deepening of soil depth.(2)The growth of flue-cured tobacco was significantly promoted by water-permeability plastic film.After transplanting,the growth parameters(plant height,stem girth,leaf length,leaf width,leaf area)were monitored dynamically.The results showed that water-permeability plastic film significantly promoted the growth and leaf elongation of flue-cured tobacco.In the33 days after transplanting,the effect of water-permeability plastic film was particularly significant.This phenomenon is mainly due to the less rainfall before the rainy season can be effectively utilized by water-permeability plastic film compared with ordinary plastic film.(3)The chemical composition of flue-cured tobacco leaves was coordinated by waterpermeability plastic film.At the end of field growth,the 15 th leaf of tobacco plant was sampled to determine the main chemical components.The results showed that the contents of total sugar,reducing sugar and potassium in tobacco leaves covered with water-permeability plastic film were 4.40%,8.46% and 39.81% higher than those covered with ordinary plastic film,respectively,but there was no significant difference in reducing sugar and nicotine between the two kinds of plastic film.Therefore,the sugar alkali ratio of water-permeability plastic film mulched tobacco leaves was 10.67,and the chemical components of tobacco leaves were more coordinated.(4)The yield and output value of tobacco leaf were significantly increased by waterpermeability plastic film.Corresponding to the promotion of tobacco growth,the yield of tobacco increased by 12.59% compared with the control.At the same time,due to the more coordinated chemical composition,the proportion of the first-class tobacco and middle-class tobacco proportion tobacco increased by 2.45% and 3.74% respectively.In terms of output value,water-permeability plastic film per hectare has been increased by nearly 7000 yuan.(5)Water-permeability plastic film can improve the physical and chemical properties of soil.Compared with the control,water-permeability plastic film could significantly increase the contents of available phosphorus,available potassium and organic matter in soil by 15.20%,25.51% and 13.50% respectively,and reduce the contents of total nitrogen and alkali hydrolysis nitrogen in soil by 4.19% and 29.77% respectively.Above all,water-permeability plastic film in tobacco field can effectively promote the water into the soil,reduce the evaporation of water,and improve the utilization rate of rainwater resources,especially before the rainy season.Higher soil water content and temperature promoted the growth of tobacco leaves and the coordination of chemical components,thereby improving the yield and quality of tobacco leaves.Therefore,water-permeability plastic film has a strong application value in Shandong tobacco area.