Commercial inundative releases ofTrichogrammatoidea cryptophlebiae [Hym.: Trichogrammatidae] againstCryptophlebia leucotreta [Lep.: Tortricidae] in citrus
| Autor: | W. J. Odendaal, Philip J. Newton |
|---|---|
| Rok vydání: | 1990 |
| Předmět: |
Tortricidae
biology business.industry Cryptophlebia fungi Pest control Biological pest control Plant Science biology.organism_classification Toxicology Trichogrammatidae Animal ecology Insect Science Botany General Agricultural and Biological Sciences business False codling moth Agronomy and Crop Science Ecology Evolution Behavior and Systematics Trichogramma |
| Zdroj: | Entomophaga. 35:545-556 |
| ISSN: | 1573-8248 0013-8959 |
| Popis: | Inundative releases of the egg parasitoidTrichogrammatoidea cryptophlebiae Nagaraja were made againstCryptophlebia leucotreta (Meyrick) on 5 commercial citrus farms in the western Cape Province, South Africa, over 2 successive seasons. A target release volume of 80 000 parasitoids ha−1 week−1 was established for releases over 29 and 33 weeks during the 2 seasons. Total seasonal volumes reached an equivalent of 2.3 and 3.8 million parasitoids ha−1 respectively. Compared with check treatments on each farm, larval population size was reduced in the release areas by 54% in the 1st and by almost 60% in the 2nd season. Percentage crop loss was reduced by 49.4±12.4 and 61.1±8.3% respectively. Treatment effects were clearly related to increases in rate of parasitism measured in both artificially-placed and in nativeC. leucotreta egg populations. Treatment efficacy is similar to that obtained with applications of chitin synthesis inhibitors but parasitoid production costs are 30% of insecticide costs. Manual distribution of parasitoids is labour intensive, however, and further studies should investigate whether inoculative releases at higher rates per week over a shorter period, are effective. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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