Effects Of Soil Cadmium Pollution And PH On Cadmium Accumulation In Different Rice Varieties

In this study,142 late rice varieties were used as materials to analyze the differences in the cadmium content of rice planted in 4 different levels of cadmium pollution and the difference of cadmium accumulation in different parts of the 8 late rice varieties,in order to study the effect of cadmium content in soil on the content of cadmium in rice and the accumulation of cadmium in different parts of the different rice varieties.At the same time,27 early rice varieties were used as materials to analyze the difference of cadmium content in rice with 3 different soil pH treatments and the difference between cadmium accumulation in different parts of 8 early rice varieties,in order to study the effects of soil pH on cadmium content of rice and cadmium accumulation in different parts of different rice varieties,and the differences of cadmium accumulation in different rice varieties were discussed.The main results are as follows:1.The results of variance analysis showed that the difference of soil cadmium content among sites,varieties,sites and varieties reached a very significant level,and the interaction of different cadmium pollution sites,varieties and sites and varieties contributed respectively 27.35%,28.08% and 21.22% of the total variance of cadmium content in rice.The difference of soil pH,varieties,soil pH and varieties reached a significant level.This shows that the cadmium content of soil,soil pH,genotype,genotype and soil cadmium content,genotype and soil pH had significant effects on cadmium accumulation in rice.2.The cadmium content of rice was significantly positively correlated with the content of cadmium in soil,which indicated that the higher the content of cadmium in the soil,the higher the cadmium content in rice and the accumulation of cadmium in different parts of the plant.3.The accumulation of cadmium in rice and different parts of plant under PH4.5 treatment was higher than that of PH5.5 treatment was higher than that of PH6.5 treatment,which indicated that the lower the pH value,the higher the activity of cadmium in the soil,the more conducive to the absorption of cadmium.4.The accumulation of cadmium in different parts of the plant showed that the accumulation of cadmium in the root was greater than that of the stem was greater than that of the leave was greater than that of the rice.And the accumulation of cadmium in second elongated stems was greater than that of the first elongated stem was greater than that of ear node.Among them,the correlation between the accumulation of cadmium in ear node and cadmium content in rice was the highest.5.The cadmium accumulation characteristics of rice cultivars were significantly different.Under the condition of uncontaminated soil or moderate pollution,the proportion of cadmium accumulation in the roots of Changliangyou 1408 and Changliangyou 1419 was larger.The proportion of cadmium accumulation in their stem was larger,and the proportion of cadmium accumulation in their rice was less when the condition of severe soil pollution.It was explained that the low accumulation of cadmium in these two varieties is mainly due to the weak transport capacity of cadmium.The total accumulation of cadmium in plants of Taiyou 390,Tianyouhuazhan and 464S/4WH0859 at 3 test points were all high,indicating that the main reason for the high cadmium content of their rice was that the cadmium absorption capacity of the plant was stronger.The cadmium absorption ability of low cadmium control varieties of Xiangwanxian 12 and Xiangwanxia 13 was poor under the condition of unpolluted soil,and under the condition of moderate or severe soil pollution,the poor transport capacity of cadmium was the main reason for the low cadmium content in their rice.