Abstract:
This study aimed to determine whether leaf extracts from seven Eruca vesicaria subsp. sativa cultivars and their biochemically active compounds (glucosinolates and downstream-derived products) inhibit mycelia growth of three well-known pathogenic oomycetes, Phytopythium chamaehyphon, Phytopythium vexans and Phytophthora citrophthora; being the most significant in the development of Kiwifruit Vine Decline Syndrome (KVDS). Leaf extract quantity of 10, 20 and 30 mg were inoculated in Petri dish (90 mm Ø, each 22 mL of liquid medium - Potato Dextrose Agar), for in vitro bioassays. A pathogen plug was placed in the centre of each plate and the Oomycota colony perimeter was marked 5 days after inoculation. Radial colony growth was measured from 4 marks per plate 5, 10, and 15 days after inoculation, further elaborated with Image J software image analysis. Growth rates for all strains were inhibited by around 67% after 15 days. This was most pronounced when applying the highest concentration of leaf extract. By using Liquid Chromatography Mass Spectrometry (LC-MS) and Gas Chromatography Mass Spectrometry (GC-MS), fifteen glucosinolate compounds, of which glucosativin was found in the highest quantity, were identified. Concentrations of hydrolysis products produced by leaves (erucin and sativin) were also investigated, and were significantly associated with colony radial growth, especially towards Pp. chamaehyphon and Pp. vexans. Three downstream products of glucosinolates (two pure isothiocyanates, AITC and PEITC; and one indole I3C; all commonly present in Brassicaceae) were also tested, and a statistically significant inhibition of growth was observed at the highest concentration (0.6 µL).
摘要:
这项研究旨在确定是否从七个芥子亚种中提取了叶提取物。紫花苜蓿品种及其生化活性化合物(芥子油苷和下游衍生产品)抑制三种众所周知的致病性卵菌的菌丝体生长,水吸虫,植物疫霉和黄疫霉;在猕猴桃藤蔓衰退综合症(KVDS)的发展中最重要。将10、20和30mg的叶提取物接种在培养皿中(90mmØ,每个22毫升液体培养基-马铃薯葡萄糖琼脂),用于体外生物测定。将病原体塞置于每个板的中心,并在接种后5天标记卵菌菌落的周长。接种后5、10和15天,每板4个标记测量放射状菌落生长,用ImageJ软件进行图像分析。15天后,所有菌株的生长速率被抑制约67%。这在应用最高浓度的叶提取物时最为明显。采用液相色谱质谱(LC-MS)和气相色谱质谱(GC-MS),15种芥子油苷化合物,其中葡萄糖蛋白酶含量最高,已确定。还研究了叶子产生的水解产物(芥酸素和sativin)的浓度,并且与菌落径向生长显着相关,尤其是对PP。chamaehypon和Pp。vexans.芥子油苷的三种下游产物(两种纯异硫氰酸酯,AITC和PEITC;和一个吲哚I3C;所有常见于十字花科)也进行了测试,并且在最高浓度(0.6µL)下观察到统计学上显着的生长抑制。