除草剂对桃树生理特性和流胶的影响

Effects of Herbicides on Physiological Characteristics and Gummosis of Prunus persica

以盆栽‘霞晖8号’水蜜桃为材料,通过连续3年使用草甘膦和百草枯除草,研究除草剂对桃树营养生长、矿质元素吸收、相关酶活性、光合作用及流胶变化等的影响,为除草剂的科学使用及其土壤环境评价提供理论参考。结果表明:(1)连续3年喷施除草剂后,‘霞晖8号’枝条和叶片淀粉含量显著降低,草甘膦处理的枝条和叶片可溶性糖含量显著低于对照,而其新梢长度、粗度、节间长以及主干周长未受到显著影响。(2)使用2种除草剂后桃树叶片N、P、K及Fe元素含量总体高于对照,但草甘膦处理显著降低了Mn元素的含量。(3)土施百草枯显著提高了桃树叶片电解质渗漏率及过氧化氢酶(CAT)和过氧化物酶(POD)的活性,草甘膦处理显著降低了叶片14:00至16:00的净光合速率(Pn)。(4)田间调查发现,连续使用2种除草剂都会造成‘霞晖8号’流胶病发病率和病情指数明显升高,桃园应尽量避免除草剂的使用。

Taking ‘Xiahui 8’ [Prunus persica （L.） Batsch.] as test materials, this paper studied the effects of herbicides （glyphosate and paraquat） on vegetative growth,mineral element absorption,related enzyme activities,photosynthesis and gummosis in peach. The results showed that： （1） on the 3rd year after spraying herbicides （glyphosate and paraquat）, the starch content in leaves and branches decreased and the soluble sugar content in leaves and branch decreased significantly after spraying glyphosate. （2） The N, P, K and Fe element contents in leaves raised while the Mn element contents in leaves was decreased significantly after spraying glyphosate. （3） On the 3rd year after spraying paraquat, the electrolyte leakage rate,catalase （CAT） and peroxidase （POD） activities in leaves raised. Glyphosate showed obvious influence on photosynthesis of ‘Xiahui 8’. The leaf photosynthetic rate （Pn） between 14：00 and 16：00 was lower than that of the control. （4） Investigations in the field showed that the gummosis incidence and disease index of ‘Xiahui 8’ increased after spraying glyphosate and paraquat. We should avoid using systemic herbicides in peach orchard.