To screen out suitable herbicides for peach nurseries, we treated the potted seedlings of the peach rootstock 'Nemaguard' with eleven herbicides under recommended doses to investigate the changes of physiological indices and comprehensively evaluate the safety of different herbicides using principal component analysis (PCA). The results showed that soil application of quizalofop-p exhibited no detectable phytotoxicity on rootstock seedlings, while the remaining herbicides generated multiple symptoms, including green loss, wilting, spot, and withering. Starane caused rapid wilting and death, with a 100.0% phytotoxicity index (PI). Soil application of n-(phosphonomethyl)glycine, glufosinate-ammonium, acetochlor, and MCPA-Na showed a PI＞65.0%. As compared with the control, all herbicides inhibited leaf area growth to varying degrees, with a 10.0%-56.2% and 5.8%-44.4% reduction in young leaf area and mature leaf area, respectively. All herbicides, except quizalofop-p, increased the electrolyte permeability of leaf and root tip cells by 21.2%-145.0% and 36.9%-291.4%, respectively, and significantly inhibited root growth. The total root length, root surface area, root volume, and the number of root tips significantly decreased by 37.3%-75.3%, 35.7%-83.0%, 44.3%-89.9%, and 42.6%-73.7%, respectively. Although net photosynthetic rate (Pn) and transpiration rate (Tr) of leaves were not significantly affected by quizalofop-p, mesotrione-atrazine, MCPA-Na·bentazone, bensulfuron-methyl·quinclorac, and bensulfuron-methyl·acetochlor, there was significant reduction of 29.6%, 28.9%, 28.4% and 27.9% in Pn and 21.9%, 29.2%, 26.4%, and 19.7% in Tr post soil application of n-(phosphonomethyl)glycine, glufosinate-ammonium, acetochlor, and MCPA-Na. The overall safety ranking of the 11 examined herbicides is as follows: quizalofop-p>bensulfuron-methyl·acetochlor>bensulfuron-methyl·quinclorac>esotrione·atrazine> auizalofop-p·fluoroglycofen>acetochlor>MCPA-Na·bentazone>MCPA-Na>n-(phosphonomethyl)glycine>glufosinate-ammonium>sterane.
为筛选出适于桃苗圃利用的除草剂,以桃砧木品种‘Nemaguard’幼苗为材料,通过土施11种推荐剂量的除草剂,研究不同除草剂处理后桃砧木幼苗药害等级、营养生长、根系结构、叶片光合特性等生理指标的变化,并基于主成分分析对不同除草剂的安全性进行综合评价。结果表明: 土施精喹禾灵对桃砧木幼苗无明显药害,而其他10种除草剂处理后,砧木幼苗表现出不同程度的失绿、萎蔫、斑枯等症状。氯氟吡氧乙酸异辛酯造成砧木幼苗迅速萎蔫枯死,药害指数(PI)为100.0%,土施草甘膦异丙胺盐、草铵膦、乙草胺和二甲四氯钠后,PI均超过65.0%。与清水对照相比,所有除草剂均不同程度抑制砧木幼苗叶面积增长,其中幼叶面积和成熟叶面积分别减小10.0%～56.2%和5.8%～44.4%。除精喹禾灵外,供试除草剂均提高了砧木叶片和根尖细胞电解质渗透率,并显著抑制砧木根系生长,其中叶片和根尖细胞电解质渗透率较对照分别上升21.2%～145.0%和36.9%～291.4%,总根长、根表面积、根体积和根尖数分别减少37.3%～75.3%、35.7%～83.0%、44.3%～89.9%和42.6%～73.7%。精喹禾灵、硝磺·莠去津、二甲·灭草松、苄·二氯、苄·乙对砧木幼苗叶片净光合速率(Pn)和蒸腾速率(Tr)的影响不显著,而土施草甘膦异丙胺盐、草铵膦、乙草胺、二甲四氯钠后,砧木幼苗叶片Pn和Tr分别显著降低了29.6%、28.9%、28.4%、27.9%和21.9%、29.2%、26.4%、19.7%。11种除草剂的总体安全性评价排序为:精喹禾灵>苄·乙＞苄·二氯>硝磺·莠去津>精喹·乙羧氟>乙草胺>二甲·灭草松>二甲四氯钠>草甘膦异丙胺盐＞草铵膦>氯氟吡氧乙酸异辛酯。.
Keywords: comprehensive evaluation; herbicide; peach rootstock; safety.