Efect of plant extracts applied in soil on sclerotinia sclerotiorum and common bean plants

ABSTRACT The pathogen Sclerotinia sclerotiorum can attack over 400 plant species such as potatoes, soybeans and sunflowers. This study aimed to identify the most adequate soil:sand proportion for the carpogenic germination of S. sclerotiorum sclerotia, as well as to evaluate the effect of plant extracts and their fractions on the carpogenic germination of sclerotia and on common bean plants. To identify the most adequate soil:sand proportion, the percentage of carpogenic germination was calculated. To evaluate the effect of plant extracts and fractions on sclerotia, the extracts and fractions were applied on the day the experiment was installed and after 30 days in soil:sand (1:1) substrate infested with sclerotia. To evaluate the effect of plant extracts and fractions on bean plants, the plant extracts were sprayed on plants at 30 days after sowing. Sclerotia showed greater carpogenic germination at 1:1 and 1:2 soil:sand substrate proportions. There was lower carpogenic germination for the ethyl acetate fraction obtained from vetch and the ethyl acetate fraction from S. terebinthifolius when applied at 30 days after the experiment was installed. The extracts did not present phytotoxicity to bean plants.摘要：核盘菌（Sclerotinia sclerotiorum）可侵染马铃薯、大豆、向日葵等400余种植物。本研究旨在确定最适宜核盘菌菌核产囊萌发的土砂比，并评价植物提取物及其组分对菌核产囊萌发以及普通菜豆植株的影响。为确定最优土砂比，本研究通过计算产囊萌发率开展相关评估。为评价植物提取物及组分对菌核的影响，分别于实验设置当日，以及在接种菌核的土砂比1:1基质中培养30天后施加提取物及组分。为评价植物提取物及组分对菜豆植株的影响，于播种后30天对植株喷施植物提取物。结果显示，菌核在土砂比为1:1和1:2的基质中具有更高的产囊萌发率。当于实验设置后30天施加时，野豌豆来源的乙酸乙酯组分以及巴西乳香树（S. terebinthifolius）来源的乙酸乙酯组分对应的产囊萌发率更低。所有供试植物提取物均未对普通菜豆植株产生植物毒性。