Effect of nitrogen rates on the whitefly (Bemisia tabaci) population infesting chilli (Capsicum annum L.)

Bemisia tabaci (Gennadius) is considered the most important whitefly species harmful to agriculture. Experiments were conducted at MARDI Station in Jalan Kebun, Klang, Selangor from 9 September 2006 to 11 November 2007. The objective of this study was to evaluate the population of whitefly on chilli plants fertilised with different rates of nitrogen (0, 33, 43, 53 g/plant). The results showed that high rates of nitrogen treatment significantly (P<0.05) increased B. tabaci immature population as compared to lower rate treatments. The mean number of B. tabaci immature per plant stratum was significantly different (P<0.05) among plant strata as well as among the treatments. Generally, the mean number of B. tabaci eggs and larvae was significantly (P<0.05) greater in the upper strata than in the middle and lower plant strata. Whereas, the mean number of B. tabaci pupa was significantly greater in the lower strata than in the upper and middle plant strata. The mean number of B. tabaci immature was significantly different (P<0.05) among the sampling periods in all treatment. Generally, B. tabaci population was significantly greater during the early season and gradually declined as the season progressed except during the third and seventh week after transplanting

A taxonomic update of Takahashi’s historic collection of mealybugs (Hemiptera: Pseudococcidae) from Malaysia and Singapore

Dr. Ryoichi Takahashi collected mealybugs (Hemiptera: Coccomorpha: Pseudococcidae) from Peninsular Malaysia and Singapore in 1943–1944, and mounted them in 39 permanent slide mounts using Canada balsam. The slides are deposited in the Department of Agriculture, Kuala Lumpur, Malaysia. The objective of this research was to update the identification of Takahashi’s specimens using recent taxonomic keys. Some preparations on cavity slides were re-mounted to facilitate identification. The re-mounted specimens, and those on the original slides, were re-examined and 12 species were identified. The Takahashi samples of Pseudococcus comstocki (Kuwana) and Rastrococcus mangiferae (Green) are the earliest records of these species from Peninsular Malaysia

NEW INDONESIAN COUNTRY RECORDS AND SPECIES INFORMATION FOR MEALYBUGS (HEMIPTERA PSEUDOCOCCIDAE) IN WIRJATI’S HISTORIC COLLECTION

Between 1955 and 1960, a collection of slide-mounted mealybugs (Hemiptera: Coccomorpha: Pseudococcidae) was prepared by Mrs Wirjati, using samples collected between 1916 and 1960 from a variety of hosts in Indonesia. The collection is a record of which species were established in the country in 1960. The slides, deposited at the Indonesian Ministry of Agriculture in Java, are the earliest material in the national mealybug collection. There are 181 temporary slide mounts of unstained, waxy mealybugs mounted in agar or gum chloral media that have dried out to varying degrees. Specimens were retrieved from 50 representative slides and re-mounted as stained, archival mounts in Canada balsam. The method used to retrieve the specimens from the old mounts is described. The re-mounted specimens were re-identified using up-to-date, published identification keys, resulting in new identities for most of the  specimens. Fifteen species belonging to 12 genera were identified, however specimens from four of the slides  could not be identified beyond genus level. The Wirjati slides of Antonina thaiensis Takahashi, Hordeolicoccus nephelii (Takahashi) and Paraputo corbetti (Takahashi) are new country records. The differences between the fauna in Wirjati’s collection and that found in Indonesia today are discussed

Aphidophagous coccinellids (insecta: coleoptera) in chili (capsicum annuum L.)ecosystems in Malaysia

The study was aimed to record and making a list of the aphidophagous coccinellids that preying on aphid, aphis gossypii glover (homoptera:aphididae)colonizing chili (capsicum annuum L) crop in Malaysia. The study was carried in chili fields at Mardi researsh stattion jalan kebun, Selangor, Malaysia from december 25, 2003 to february 29 2004. The A.gossypi infested chili plants were inspected by walking along the beds and adults of coccinellids seen were collected and brought back to laboratory for species indentification. A total of five coccinellids species were recorded namely the menochilus sexmaculatus fabricius, coelophora inaequialis (faricius) coccinella transversalis fabricius, harmonia occtomaculata (fabricius) and coelophora bissellatta (mulsant)(coleoptera: coccinellinae).Of these. M.sexmaculatus was the most abundant species colonizing chili followed by C.inaequialis, H.occtomaculata,and C.bissellatta. It is imperative to conduct further study on the impact of these spesies when alone or in combination as it has the potential to be on aphid population candidate for biological control agent of A.gossypii