Screening Of Flax Varieties Suitable For Planting In Heavy Metal Contaminated Soil In Hunan And Its Application

Flax is an important economic crop,with excellent characteristics and a variety of com mercial uses,widely used in fiber,medicine,edible oil,composite materials and feed.In rece nt years,due to various constraints,the shortage of flax raw materials in China is growing.Fl ax is moved to the south,which has opened a new way for the adjustment of agricultural ind ustrial structure and the development of flax industry in southern provinces.The main conten ts and results of this study are as follows.1)In order to explore the ecological adaptability of different Flax Varieties in cadmiu m contaminated soil in South China,the flax varieties in different locations and fields were c ompared,and the good flax varieties suitable for planting were selected.The results showed t hat through the comparison of agronomic characters and yield characters of different Flax Va rieties in different experimental sites,the most suitable varieties were selected:"Jinya 10"an d"neiya 9".2)In order to explore the feasibility of summer sowing flax in cadmium contaminated soil in South China,pot experiment was conducted to study the agronomic characteristics,bi ological characteristics and heavy metal absorption of summer sowing flax in cadmium cont aminated soil in South China.The results showed that the growth period of summer sowing flax in South China was about187 days.Heavy metals have little effect on the growth period of southern summer sown flax,the performance of main agronomic traits is poor,not reaching the level equivalent to that of southern winter flax.In terms of heavy metal absorption,southern summer flax performs better.The tolerance index of all varieties reached more than 99%,showing high tolerance to the heavy metal cadmium;the enrichment index was generally high,with the lowest being 2.060 and the highest being11.403,indicating that the 7 tested varieties had good absorption of heavy metals in the soil.At the same time,the transfer coefficient of the 7 tested varieties is also between0.5～1.1.Tianya No.9 was the best,and its original stem yield was the highest,353.76 kg/mu.The tolerance index,enrichment coefficient and transport coefficient were 0.999,11.086and 1.07 respectively.3)By planting flax in the polluted soil of Jiacheng village,Yonghe Town,Liuyang C ity,the effects of soil heavy metal cadmium and non-metallic sulfur pollution on the growth of flax were studied with 5 different growth types and 3 representative plots for each field.T he results showed that the correlation coefficients of cadmium content in soil with flax origin al stem yield and seed yield were-0.15328 and-0.15167,respectively.There was a significant negative correlation.4)In order to study the economic and ecological benefits of substituting planting flax in cadmium contaminated soil,the agronomic characteristics of flax and the heavy metals in soil and plant were investigated in xiadawu group and Xinjian group of cadmium contaminat ed soil in Jiacheng village,Yonghe Town,Liuyang City.The results showed that the plant hei ght of neiya 9 was above 79.20cm,the height could reach 108.94cm,the process length was above 62.52cm,the stem diameter was up to 3.50mm,the original stem yield was up to 4337.81kg/hm2,and the seed yield was 468.07kg/hm2.In the aspect of heavy metal absorption,t he enrichment factor is high,the highest can reach 6.752,indicating that neiya 9 has a good a bility to absorb heavy metals in soil.The net income is 1027.76 yuan/667m~2.The results sh owed that the economic and ecological effects of flax planting in cadmium contaminated soil were better.