外来杂草睫毛婆婆纳的化感作用

睫毛婆婆纳(Veronica hederifolia L.)又名常春藤叶婆婆纳,为玄参科婆婆纳属越年生或一年生草本植物.睫毛婆婆纳原产欧洲、西亚和北非等地中海沿岸国家,是当地极为重要的麦田杂草.该种在20世纪80年代传入我国,在江苏南京和浙江定海有分布.通过其地上部分的水浸提液对小麦、油菜、早熟禾和高羊茅种子的萌发培养试验,研究睫毛婆婆纳的化感效应.结果表明,睫毛婆婆纳地上部分的水浸提液对4种受试植物种子萌发、根长和幼苗干重均有显著的抑制作用,浓度越高,抑制作用越强.在3个生测指标中,根长表现最敏感.在最高浓度(0.20 g/ml)下,高羊茅、早熟禾、小麦和油菜根长的化感效应指数分别为-0.392 9、-0.511 5、-0.118 0和-0.776 5.不同植物对睫毛婆婆纳化感作用的敏感程度也不同, 油菜最敏感, 其种子萌发、根长和幼苗干重在最高浓度(0.20 g/ml)下的化感效应指数分别为-0.345 4、-0.776 5和-0.388 9.     

紫茎泽兰化感作用对6种贵州本地植物种子萌发的影响

为了解紫茎泽兰对贵州本地植物种子萌发的影响,以紫茎泽兰作为供体,选取6种植物种子作为受体,采用培养皿滤纸法测定紫茎泽兰叶片浸提液对贵州本地植物种子萌发的化感作用。结果表明:紫茎泽兰化感物质对马尾松、苣荬菜各发芽参数和杉木胚根生长呈现出低促高抑的现象,而对其他几种受体表现为抑制作用,随着浸提液浓度的升高,对各受体的抑制作用显著增强。各受体植物种子萌发对紫茎泽兰化感作用的敏感程度不同,马尾松、苣荬菜、油茶对紫茎泽兰的化感物质的抑制作用不敏感,杉木、板栗、火棘则较为敏感。     

Quantification of momilactone B in rice hulls and the phytotoxic potential of rice extracts on the seed germination of Alisma plantago‐aquatica

The occurrence of herbicide‐resistant weeds has boosted interest in the use of crop allelopathy as a potential alternative to herbicides for weed control in rice (Oryza sativa). The phytotoxic compounds that are released by rice could help to enhance its competitive ability and improve weed management. This study aimed to screen rice genotypes for phytotoxic activity, quantify the amount of momilactone B in various rice tissues, and identify the potential parental lines for quantitative trait locus analysis. Therefore, a total of 41 cultivars from germplasm collections was evaluated for their effects. Significant differences were found among the rice cultivars in their ability to reduce the germination, root growth, and root dry weight accumulation of Alisma plantago‐aquatica. The leaf extract was the most inhibitory to germination. Out of the five cultivars that were tested, momilactone B was detected in four of them: Marateli, Kizilirmak, Karadeniz, and Kiziltan. Karadeniz and Kiziltan were identified as the rice cultivars with a high momilactone B content in the tissues and therefore they could be used in breeding programs to enhance the phytotoxic potential of rice. The development of a rice cultivar with proven allelopathic characteristics could provide an environmentally friendly and low‐cost approach for the control of A. plantago‐aquatica.     

不同百里香茎浸提液对黄瓜种子发芽率的影响

用蒸馏水、10%乙醇溶液和10%丙酮溶液浸提百里香茎段,将浸提液进行不同比例的稀释,用稀释后的浸提液处理黄瓜种子,统计发芽率,结果表明3种浸提剂的浸提液处理下,水浸提液处理的发芽率最高,其次为乙醇浸提液,丙酮浸提液的发芽率最低;1∶5的百里香茎水浸提液对黄瓜种子的萌发具有促进作用,而1∶1、1∶10、1∶15的处理对黄瓜种子的萌发具有抑制作用;百里香茎丙酮浸提液对黄瓜种子的萌发具有抑制作用,且1∶10的处理抑制能力相对其他处理较弱;百里香茎乙醇浸提液对黄瓜种子的萌发具有抑制作用,且1∶1的处理抑制能力较其他处理弱。     

紫茎泽兰对7种牧草种子萌发及幼苗生长的化感作用

检测了紫茎泽兰地上部分榨取液对7种牧草种子萌发和幼苗生长的化感作用。结果表明：（1）紫茎泽兰地上部水浸提液对7种供试牧草种子的萌发均表现为强烈的抑制作用（P 〈0.05）,对光叶紫花苕种子萌发的抑制作用显著小于对紫花苜蓿、白三叶、红三叶、东非狼尾草、非洲狗尾草和鸭茅种子萌发的抑制作用（P 〈0.05）;（2）从幼苗生长的测定结果分析,紫花苜蓿,红三叶和光叶紫花苕对低浓度紫茎泽兰叶片水提液不敏感,对高浓度提取液较敏感。白三叶、鸭茅、非洲狗尾草和东非狼尾草对紫茎泽兰的化感作用较敏感;（3）根据化感作用检测结果,分析认为光叶紫花苕、红三叶和紫花苜蓿是紫茎泽兰替代种植的适宜草种。