连作土灭菌对葡萄生长及根系分泌特性的影响

Effect of sterilized replant soil on grape growth and root exudation characteristics

为探讨葡萄连作障碍产生的原因,采用盆栽模拟试验,对葡萄连作土壤进行蒸汽灭菌,研究连作土灭菌后葡萄植株生长及根系分泌特性的变化。结果表明,连作土灭菌显著增加了葡萄植株的株高和茎粗,其中以7月份的增加幅度最大,分别比连作土增加了1.51倍和0.14倍,地上和地下鲜质量随着生长期的延长也表现出显著增加的趋势,以9月份的增加幅度最大,分别增加了1.18倍和1.09倍。并且连作土壤灭菌后葡萄叶片SOD酶活性增强,MDA含量降低,根系活力随生长期的延长,表现出先下降再上升的趋势。另外,研究发现连作土壤灭菌后葡萄根系分泌的还原糖及氨基酸总量显著降低,分别比连作土壤降低了72.60%和91.10%;氨基酸的种类及其含量也发生改变,其中Ile、Leu和Tyr3种氨基酸未达到检测水平,其他氨基酸含量降低。可见,对连作土壤进行有效的灭菌后,可以改变根际微生态的核心因素即根系分泌物的成分及含量,促进植株的生长,减轻葡萄的连作障碍,进而证实了土壤生物因素是葡萄连作障碍产生的重要原因之一。

In order to study the effect of sterilized plant soil on the growth and root exudation characteristics of grapevines,a simulated experiment was carried out by potted culture with steam sterilized replant soil. The results showed that the plant height and stem diameter from grapevine grown on sterilized replanting soil were increased,and the most increasing extent presented in July which increased by 1.51 times and 0.14 times; the shoot fresh weight and root fresh weigh were also increased along with prolonging growth period,and the most increasing extent presented in September which increased by 1.18 times and 1.09 times. After replanting soil sterilized,SOD enzyme activity increased,but MDA content decreased,and root activity was enhanced first and then declined. The content of reducing sugar and amino acid of root exuded for grapevine grown on sterilized replanting soil deceased by 72.60% and 91.10%,comparing with that grown on replanting soil,and the amino acid composition of root exudation also changed,appeared as Ile,Leu and Tyr not reaching the detection level,and the contents of other amino acids decreased. So,it is believed that the biological factor played a causal role in the development of grape replant disease,and sterilization of replant soil could change the composition and content of root exudation,promote plant growth and alleviate grape replanting obstacle.