Abstract
This study aimed to determine the inhibitive or stimulatory effects of leaf extracts from two Brassica rapa subspecies on the hyphal growth of two well-known entomopathogenic fungi, Cordyceps fumosorosea and Beauveria bassiana. Extract concentrations of 50, 25, and 10% w/v based on leaf fresh weight were prepared from turnip (B. rapa subspecies rapa) and bok choy (B. rapa subspecies chinensis) 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.
Highlights
The Brassicaceae, commonly known as crucifers, have been studied extensively for secondary metabolites, known as glucosinolates, found exclusively in their tissues [1].When the plant is mechanically damaged, such as being fed on by an arthropod or infected by a plant pathogen, cellular breakdown exposes the glucosinolates stored in the leaves to degradative enzymes known as myrosinases [2]
Significant differences in fungal colony radial growth at 15 days were detected among treatments for all four fungal strains on potato dextrose agar (PDA) with bok and turnip leaf extracts
Based on a previous in vivo where yellowmargined beetleto adult serve based on a previous in vivo study where the yellowmargined leaf beetle adult was was rarely infected by C. fumosorosea Apopka strain while feeding on bok choy leaves rarely infected by fungus
Summary
The Brassicaceae, commonly known as crucifers, have been studied extensively for secondary metabolites, known as glucosinolates, found exclusively in their tissues [1].When the plant is mechanically damaged, such as being fed on by an arthropod or infected by a plant pathogen, cellular breakdown exposes the glucosinolates stored in the leaves to degradative enzymes known as myrosinases [2]. The genus Brassica, with approximately 159 species, is considered the most important of this family because it includes many economically important crops [11], such as kale, cabbage, bok choy, cauliflower, broccoli, turnip, rapeseed, and canola. Production of these cruciferous crops is often difficult, and yield is significantly reduced by arthropod pests such as the yellowmargined leaf beetle, Microtheca ochroloma Stål, especially in organic production [12].
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
