Authors:
Ngugi CN., Mbaka, JN., Wachira, PM,
and Okoth, S
,Kenya |
Abstract:
The American leaf miner (Tutaabsoluta)important invasivepest of tomato in Kenya. The pest
infests the crop at any growing stage causing yield loss of up to 100%. Due to limited pest
management options, farmers are currently using synthetic pesticides despite their negative
effects to the environment. Infectivity of five indigenous entomopathogenic nematode (EPN)
isolates (TK1, S86, 97, 75 and R52) on 2nd and 3rd larval stages of T. Absolute was evaluated
under laboratory conditions. The larvae were subjected to different EPNs concentrations (100,
150, 200, and 250/ml) and the control. Larval mortality (infectivity) was recorded at 24 hour
interval up to 120 hours. All the tested EPN isolates infected and reproduced within T. absolute.
IsolateTK1 caused the highest mortality (100%;92 5%) while isolate 97 recorded the least
mortality (402%; 48±\ 8%), on 2nd and 3rd larval instars respectively at concentration 100 in
the48 hour exposure time. Larval mortality increased overtime with isolate 97 recording 80
increase by the 120 hour. A significant difference(P 0.05)in mortality between EPN isolates and
different time intervals was recorded. There was no significant difference (P>0.05) between
mortality of 2nd and 3rdT. absoluta instars. The findings of this study revealed that the five EPN
isolates were infective to the T.absoluta larvae. The five EPN isolates are recommended for
further development for use in the integrated management of T. Absoluta |
