γ-氨基丁酸对毛桃幼苗生长及镉积累的影响

Effects of γ-aminobutyric Acid on Growth and Cadmium Accumulation of Peach Seedlings

以毛桃幼苗为试材,采用盆栽试验法,在镉胁迫条件下对毛桃幼苗施用不同浓度的γ-氨基丁酸(GABA),研究了GABA对毛桃幼苗生长及镉积累的影响,以期为桃安全生产提供参考依据。结果表明:1.0 mg·L^(-1)镉处理降低了毛桃幼苗的株高、生物量和光合色素含量。施用0.1、0.5、1.0、2.0 mmol·L^(-1)GABA提高了毛桃幼苗的生物量和光合色素含量。当GABA浓度为0.5 mmol·L^(-1)时,毛桃幼苗的根系生物量、地上部分生物量、叶绿素a含量、叶绿素b含量及类胡萝卜素含量均最高,分别较镉处理增加了36.34%、28.79%、49.86%、85.62%和38.10%。随着GABA浓度的升高,毛桃幼苗的根系镉含量呈降低趋势,而地上部分镉含量及转运系数呈增加趋势。施用0.1、0.5、1.0 mmol·L^(-1)GABA后均显著降低了毛桃幼苗地上部分的镉含量,分别较镉处理降低了43.92%、30.86%和16.42%。因此,GABA能够促进镉胁迫下毛桃幼苗的生长,且在浓度为0.1、0.5、1.0 mmol·L^(-1)时能有效降低毛桃幼苗的镉积累。

The peach seedlings were used as the test materials to carry out a pot experiment.The different concentrations ofγ-aminobutyric acid(GABA)were applied to peach seedlings under cadmium stress conditions,and the effects of GABA on the growth and cadmium accumulation of peach seedlings were studied,in order to provide reference for the safe production of peaches.The results showed that 1.0 mg·L^(-1) cadmium treatment reduced plant height,biomass and photosynthetic pigment content of peach seedlings.Application of 0.1,0.5,1.0 mmol·L^(-1) and 2.0 mmol·L^(-1) GABA increased the biomass and photosynthetic pigment content of peach seedlings.The highest root biomass,above-ground part biomass,chlorophyll a content,chlorophyll b content and carotenoid content of peach seedlings were found when the GABA concentration was 0.5 mmol·L^(-1),which increased 36.34%,28.79%,49.86%,85.62%and 38.10%,respectively,compared with the cadmium treatment.With the increase of GABA concentration,the cadmium content in the root system of peach seedlings showed a decreasing trend,while the cadmium content and translocation factor of the aboveground part showed an increasing trend.The application of 0.1,0.5,1.0 mmol·L^(-1) GABA significantly reduced the cadmium content in the aboveground part of peach seedlings by 43.92%,30.86%and 16.42%,respectively,compared with the cadmium treatment.Therefore,GABA promoted the growth of peach seedlings under cadmium stress and was effective in reducing cadmium accumulation in peach seedlings at concentrations of 0.1,0.5 mmol·L^(-1) and 1.0 mmol·L^(-1).