Abstract:
Desmodium spp. and Napier-like
grasses are widely used as push-pull systems for
mange fall armyworm (FAW) in Africa. However,
the responsible cues for the olfactory responses of
the FAW was not been identified yet. Hence, this
study was conducted to identify volatile
compounds release by Desmodium spp. and
Bachiraria brizantha plants and determine their
role on behaviour modification of FAW adults and
the larvae. Four different plant species i.e., B.
brizantha, Desmodium heterophullum, D.
triflorum and D. interim were collected, and
volatiles were extracted using dynamic head space
and solvent extraction methods. The chemical
compounds were identified using GC-MS.
Behavioural studies were conducted for selected
volatiles based on availability. This study
identified 29 volatile compounds released by
Desmodium spp. where 30 compounds were
identified from B. brizantha. Behaviour study
results indicated that females were attracted to nhexane (72.73%) and Limonene (-) (66.67%),
where naphthalene (70%) showed a repellent
behavior. Males were significantly repelled by 3-
Hexen-1-ol, Limonene (-), and Limonene (+).
Neonates significantly attract to Limonene (-)
(69.23%) and repel by 1-Octen-3-ol. Therefore, it
can be concluded that this behavior modified
volatile compounds can be used to develop
semiochemical based green pest management
strategies.
