Study On Selection Of Sensitive Demonstractive Plants To Saline Soil And The Plant Instruction Salinity Technology Research

Nowadays the process of salinity accumulation in farmland soil accelerates remarkable because of high multiple cropping index and large fertilizer input amount in protected agriculture.Soil salinization becomes a serious problem,especially in coastal area which has highly salinity background.Soil salinization not only affects the quantity and quality of crops,but also causes sharply deterioration of soil quality and sustainable production capacity.In order to maintain the production potential, people adopt plenty of treatments to improve and prevent the salinization soil,and the degree distinguish of salinization soil is the basis to control the trend. Based on plant distribution on different soil salinity in coastal area,Suaeda heteroptera Kitag,Chenopodium glaucum Linn.,Chenopodium serotinum L., Portulaca oleracea Linn.and Glycine max which are representative in high,medium or low soil salinity and widely distributed in coastal area of farmland were selected as study object.According to the results of potted cultivation in the climate chamber and glass-greenhouse,there were obviously response relations between plant height growth rate and survival rate with soil salinity.The details as followed:(1) Screening out the sensitive demonstractive plants to distributed salinition farmland soilAccording to field survey and laboratory tests,Suaeda heteroptera Kitag, Chenopodium glaucum Linn.,Chenopodium serotinum L.,Portulaca oleracea Linn. and Glycine max,which are common plants in Shanghai rural area as well as coastal area,were screened out as sensitive demonstractive plants to distribute farmland soil salinity.The results of potted cultivation tests in the climate chamber and glass-greenhouse suggested the adaptability and physiological reponses of various plants to different soil salinization degrees.Survival rate and initial height growth inhibition rate were also selected as sensitive distinguish indicator of demonstractive plants.(2) Reveal the response relationship between demonstractive plants and soil salinization degree.The potted cultivation tests in the climate chamber and glass-greenhouse suggested the response relationship between five demonstractive plants' growth state and soil salinization degree.The results show that the Suaeda heteroptera Kitag,as an extremely salt-tolerant plant,its survival rates under the condition of nine salinity were more than 50%;and the salinity demonstractive scope of Chenopodium glaucum Linn.,Chenopodium serotinum L.,Portulaca oleracea Linn.and Glycine max were reduced in sequence.The survival and height growth inhibition rate have obvious reponse relationships to different soil salinity degrees.(3) Build up a sensitive demonstractive plants system to salinization farmland soilBased on the analysis of the response relationships between the indicators of 5 kinds of sensitive demonstractive plants and 9 different salinity degrees,A set of simple and visual indicators were set up to determine 6 different soil salinity degrees whichi content of less than 0.27%,0.27～0.66%,0.66～0.78%,0.78～0.99%,0.99～1.77%,as well as more than 1.77%through complex observation of growth characteristics of the 5 plants.The sensitive demonstractive plants system is not only the directly distinguish method for salinization farmland soil evaluation or the assessment method for salinization improvement,but also provide technical support to the first-line staff to carry out the crop type selection of cultivation and the soil salinity control work.