Abstract:
A one-year survey was carried out at two fields, Al-Ramla and Al-Sabil in El-sawagi El-ganobia in Kassala State to identify the Fruit determine the seasonal abundance of the Asian fruit fly Bactrocera invadens (Drew) on guava fruit and adult emergence of the flies. A comparison was made between Al- Ramla and Al-Sabil in El-sawagi El-ganobia and Classification the fruit fly that appears in the collected specimens. In addition, to know the relationship between relative Abundance (%) of fruit fly and climatic factors and the most susceptible fruiting stage of maturity to flies infestation. An experiment was also made to identify the most preferable host plant to fruit flies. A study on the depth that constrains the adult emergence and the effect of sun light and water flooding on the pupae was also investigated. Also, a questionnaire was made among the farmers in Al- sawagi Al-ganobia,Al- shemalia and Al-shargia.
This study revealed that, the population B.invadens flies has two peaks, one in autumn (July and August) and the other in winter (January and February), and the lowest infestation was in the summer. The emergence of the adult was found to be regular all the year, but the lower emergence percentages were in the summer. Identification of the collected specimens showed the presence of Asian fruit fly and Mediterranean fruit fly at a percentage of 98% and 2%, respectively. the relative abundance increased with the increase of the relative humidity percentage particularly during autumn and winter. Within the fruiting stage of guava, the ripe stage was found to be highly infested .and was the most susceptible stage for flies’ infestation, followed by the mature and the immature stage. The fruit fly prefers guava, mango and orange and no infestation was found in lemon.
Regarding the role of cultural practices the adult eclosion decreases with the increase of flooding period. The exposure of pupae to direct sun light and heat showed that the death of the pupae increased with increase in period of exposure, and the mortality rate was found to decrease with the increase of pupae age in the same period of exposure and the percentage of adult emergence decreases when depth increased. The type of the soil was also an important factor the clay soil gave the lowest eclosion percentage while the silt and sandy soils the highest percentage of eclosion
From the questionnaire, it was shown that no guava found in Al-swagi Al-shargia and Al-swagi Al- shimalia. In addition, the questionnaire supported the results in the study. Where the farmer used of collect, burn up, bury the infested fruit, early harvesting, flooding the soil with water for long time, and cut the branch for exposure the soil to the sun light. In addition, the questionnaire included information about knowledge of the farmer with fruit fly and cultural control methods that were not mentioned in the study, and the role plant protection in the extension.
