Effect of Modes of Ridge and Nutrient Solution Irrigation on Cucumber Cultivation and Transport of Water and Salt in Soil
|School||Nanjing Agricultural College|
|Keywords||Ridge Nutrient solution Cucumber Irrigation of Water and salt transport|
Vegetable facilities is developing rapidly in recent years in our country, and yet soil secondary salinization which may lead to a series of negative effects for instance deterioration of soil, insects and disease problems and degradation on vegetable quality and quantity was set up by reasons such as unceasingly growing of cultivated years, uncontrolled use of fertilizer and special transport mode of water and salt in soil. Saline-alkali soil would inhibit the growth of plants, and brought out degradation on vegetable quality and quantity. Studies found that drip irrigate with nutrient solution could improve saline-alkali soil, as this cultivation mode would improve salt-water environment on plant root as many studies had already proved, and then result in rise of output and improvement of qulity, however the mechanism of these appearances was still unknown.The aim of this study was to analysis the mechanism of the mode ’high ridge and drip irrigation’ improving saline-alkali soil by means of contrasting ’high ridge and drip irrigation’ mode and other modes. And further select the most appropriate nutrient concentration for cucumber cultivation under ’high ridge and drip irrigation’ mode. The chief results are showed as follows:1. Cucumber growth and water-salt transport in soil of three cultivation modes were studied. Results indicated that plants under’high ridge and drip irrigation’ mode got the best growth vigor and fruit quality. This mode not only had better effects of salt wash and moisture retention of soil than other modes but also got the lowest rate and the latest time of salt return, which resulted in elevation of soil water content and reduction of soil EC value. This could be an important mechanism of ’high ridge and drip irrigation’ mode to improve the salinization of soil.2. Ions distribution in soil of three cultivation modes was studied. Results indicated that ’high ridge and irrigation’ got the largest augmenter in six soil ions in surface layer soil, conversely ’high ridge and drip irrigation’ mode had the best eluviations of Cl-、SO42-、Mg2+、Ca2+in soil, and got the least accumulation of HCO3-and Na+in surface layer soil of three modes.3. Under high ridge, mulching membrane and drip irrigation conditions, effects of different nutrition concentrations on yield, quality of cucumber and soil characters were studied. Results indicated that plant growth, fruit quality and yield of cucumber under nutrition with 2.5mS.cm-1EC value were significantly superior to those of others. Soil EC value and pH value of all soil regions had no significantly difference with that before treat except the EC value of soil in the 0-10cm depth at the middle of drippers and the pH value of soil in the 0-10cm depth at drippers. In sum,2.5mS.cm-1 EC value is the most appropriate concentration. In order to improve light soil salinization, nutrition with EC value lower than 2.5mS.cm-1 might be adopted on the seedling stage.