Cd对桑叶品质、生理生化特性的影响及其机理研究

Effect of Cd on quality, physiological and biochemical characteristics of mulberry leaves and its mechanism

土壤中不同浓度的Ｃｄ对桑叶产量、品质、生理生化特性的影响以及Ｃｄ在桑叶亚细胞各组分中分布量的研究表明，当土壤Ｃｄ浓度小于２２．３ｍｇ·ｋｇ－１时，桑叶产量、可溶性糖和含氯化合物含量高于或接近对照；桑叶叶绿素含量、细胞膜透性和超氧化物歧化酶、过氧化物酶及蛋白酶的活性无明显影响或有促进．当土壤Ｃｄ浓度大于２２．３ｍｇ·ｋｇ－１时，Ｃｄ对桑叶产量、营养物质含量、生理生化作用的影响随之明显，并表现其毒害作用．根据Ｃｄ在桑叶亚细胞组分中的分布规律．对其影响机理进行了探讨，说明桑树是一种具有一定耐Ｃｄ性的经济作物．因此，可利用其耐Ｃｄ性，在被Ｃｄ污染土地上种植桑树．

Effect of Cd on yield, quality. physiological and biochendcal characteristics of mulberry leaves and its distribution in subcellular fractions under different Cd levels in soil are studied in this paper. The results show that yield and contents of soluble sugar and N-containing compounds in leaves are higher than control or similar to control, and chlorophyll content, cell membrane permeability and activities of SOD, POD and Protease in mulberry leaf show little changal comparing with control, or even have certain promotive effect under lower Cd concentration of soil (< 22. 3 mg· kg-1). When Cd concentration in soil is higher than 22. 3 mg·kg-1, yield,nutrient contents, phySiological and biochewhcal prOPerties of mulberry leaves show distinct changes, and the injury blame heavier with the increase of Cd concentration in soil. The mechanism is analyzed by distribution of Cd in subcellular fractions of mulbo leaves.Therefore mulberry can be regarded as a kind of Cd-tolerant cash crop and it is ￣ble to aam mulberry in ac pouuted soils.