Cerritos-Garcia Daniel G, Avery Pasco B, Martini Xavier, Candian Valentina, Cano Liliana M, Cave Ronald D
Indian River Research and Education Center, Department of Entomology and Nematology, Institute of Food and Agricultural Sciences (IFAS), University of Florida, 2199 South Rock Road, Fort Pierce, FL 34945, USA.
Department of Agricultural Sciences and Production, Zamorano University, San Antonio de Oriente, Fco. Morazán, Honduras.
J Fungi (Basel). 2021 Sep 19;7(9):779. doi: 10.3390/jof7090779.
This study aimed to determine the inhibitive or stimulatory effects of leaf extracts from two subspecies on the hyphal growth of two well-known entomopathogenic fungi, and Extract concentrations of 50, 25, and 10% / based on leaf fresh weight were prepared from turnip ( subspecies ) and bok choy ( subspecies ) leaves. Each concentration was individually incorporated into potato dextrose agar plates for in vitro bioassays. The center of each plate was inoculated with 20 µL of a fungal suspension that was allowed 24 h to soak into the agar before sealing the plates and incubating them at 25 °C under a 14-h photophase. The fungal colony perimeter was marked 5 days after inoculation on two perpendicular lines drawn on the bottom of each plate. Radial colony growth was measured from 4 marks per plate 5, 10, and 15 days later. Radial growth rates for both fungi were 1.3-2.0 and 0.9-1.4 times faster with bok choy and turnip extracts, respectively, at the 25% and 50% concentrations compared to the no-extract control treatment. Therefore, bok choy and turnip leaf extracts can stimulate entomopathogenic fungus growth within 15 days. Biochemical compounds in the extracts include sesquiterpenes, α-copaene, β-selinene, γ-gurjunene, calamenene, cubenene, and α-calacorene.
本研究旨在确定两个亚种的叶片提取物对两种著名昆虫病原真菌菌丝生长的抑制或刺激作用。基于叶片鲜重，分别从芜菁（亚种）和小白菜（亚种）叶片中制备了浓度为50%、25%和10%的提取物。将每种浓度的提取物分别加入马铃薯葡萄糖琼脂平板中进行体外生物测定。在每个平板的中心接种20μL真菌悬液，让其在琼脂中浸泡24小时，然后密封平板，并在25℃、14小时光照期的条件下培养。接种5天后，在每个平板底部绘制的两条垂直线上标记真菌菌落周长。5天、10天和15天后，从每个平板的4个标记处测量菌落的径向生长。与无提取物对照处理相比，在25%和50%浓度下，小白菜和芜菁提取物处理的两种真菌的径向生长速率分别快1.3 - 2.0倍和0.9 - 1.4倍。因此，小白菜和芜菁叶片提取物可在15天内刺激昆虫病原真菌生长。提取物中的生化化合物包括倍半萜、α-可巴烯、β-芹子烯、γ-古芸烯、卡拉烯、库贝烯和α-卡拉考烯。
