Abstract
For practical control, a study was made of Scirpophaga innotata Wlk., a noxious rice stalk borer in certain regions of Java.
Caterpillars normally developed and pupated in stalks that had not reached the stage of ear formation. In paddy from before flowering, however, caterpillars entered into a resting stage (diapause), induced by food rich in carbohydrates and proteins.
After harvest diapausing caterpillars remained in the stubble. Further development started after at least 3 months diapause and the stubble and the soil were wetted. This was usually with the first heavy rainfall in the west monsoon. The longer the diapause the sooner moths appeared; with a 3 months' diapause moths emerged 80 days after rainfall began, with a 6 months' diapause after a mean of 33 days.
The cultural practice of timed rice sowing was introduced. Sowing started not earlier than one month after the first rains had fallen. Thus infestation of the young fields was prevented for the greater part.
Caterpillars normally developed and pupated in stalks that had not reached the stage of ear formation. In paddy from before flowering, however, caterpillars entered into a resting stage (diapause), induced by food rich in carbohydrates and proteins.
After harvest diapausing caterpillars remained in the stubble. Further development started after at least 3 months diapause and the stubble and the soil were wetted. This was usually with the first heavy rainfall in the west monsoon. The longer the diapause the sooner moths appeared; with a 3 months' diapause moths emerged 80 days after rainfall began, with a 6 months' diapause after a mean of 33 days.
The cultural practice of timed rice sowing was introduced. Sowing started not earlier than one month after the first rains had fallen. Thus infestation of the young fields was prevented for the greater part.
Original language | Dutch |
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Qualification | Doctor of Philosophy |
Awarding Institution | |
Supervisors/Advisors |
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Award date | 5 Feb 1925 |
Place of Publication | Wageningen |
Publisher | |
DOIs | |
Publication status | Published - 5 Feb 1925 |
Keywords
- insects
- plant pests
- rice
- oryza sativa
- lepidoptera
- indonesia
- java
- netherlands east indies