Primary Study On The Effect Of Allelopathy On Ratoon Sugarcane Seedling Etiolation

In recent years, the research group have studied on ratoon sugarcane seedling etiolation in many aspects,which appear in many sugarcane area of Guangxi.We have proved it indeed will seriously affect the yield and quality of sugarcane.On the basis of existing research evidence to suggest that allelopathy may have a certain relationship with the seedling etiolation.To study the correlation between allelopathy and ratoon sugarcane seedling etiolation, this experiment selected Fusui county where ratoon sugarcane seedling etiolation pHenomenon is serious as the research object. Taking four representative blocks named XinNingDaTang,QuLiQuFeng,QuLiBiJi,,ChangPingPingBai.field, fixed position, fixed plant, regularly investigation. And sampled in the same or near blocks, taking the normal ratoon sugarcane plants and new cane plants as control.Determination of the sugarcane roots, root nutrient, rhizosphere soil physical and chemical properties, nutrient status in rhizosphere soil and allelochemicals in rhizosphere soil.The test results show that:the ratoon cane ratoon etiolated seedlings compring with normal ratoon sugarcane seedlings and new cane seedlings:rootsnumber is lower, especially white root number, root activity is lower, the root membrane permeability is more, content of mineral nutrients in roots is lower, the soil pH value is lower, the soil urease and catalase activityis is lower. But the soil nutrient level is not lower, the rhizosphere soil content more pHenolic acidallelo, more types of allelopathy matter, rhizosphere soil leaching allelopathic inhibitoryeffects strength is greater.The main conclusions:the main reason of ratoon sugarcane seedling etiolation is more allelochemicals accumulated in rhizospHere soil, such as alkanes, esters, acids, pHenols, organic acids and other small molecules, especially pHenolic allelochemicals, it not only cause damage to sugarcane root, damage root cell membrane, increase cell membrane permeability, inhibite of root activity, but also can inhibit the occurrence and growth of new sugarcane roots, will impact on soil physical and chemical properties. Comprehensive effect of multiple factors result in sugarcane root absorption capacity of water and nutrient deficiencies. This is one of the important reasons of ratoon sugarcane seedling etiolation.