No abstract

We conducted monthly monitoring of lepidopterous moth borers in four sugarcane fields in Java, Indonesia, from May 2009 to May 2011. Fields sampled belonged to Pesantren Baru, Jombang Baru, Gondang Baru and Subang sugar factories. Three main moth borer species were found to inflict damage to sugarcane plantations in all regions, and these are the stalk borers Chilo sacchariphagus (Bojer) and Chilo auricilius Dudgeon and the top borer Scirpophaga excerptalis (Walker). Tetramoera (Eucosma) schistaceana (Snellen) was also encountered but only caused minor damage. Borer populations increased with plant age and reached a peak around January – May in most cases, with the onset of rainfall triggering population rise. All borers coexisted in the same plant with no evidence of competition between the two stalk borers (C. sacchariphagus and C. auricilius) over their specific feeding location (internode) or between the two stalk borers and the top borer (S. excerptalis) over the same plant. This suggests that an infestation by one species does not make the plant less desirable to be colonised by another. Parasitism rates by natural enemies were very low which reflects the challenges facing biological control efforts in Java. Knowledge generated through this project will improve our understanding of borer dynamics in South East Asia and will enhance our preparedness for potential introduction by any of these pests into Australia

No abstract

Sugarcane streak mosaic virus (ScSMV) is the most important viral disease of sugarcane in Indonesia with distribution in almost all commercial sugarcane plantations. The disease causes significant yield losses of both cane tonnage and sugar yield. The use of resistant varieties is the best approach for controlling viral diseases. This study aims to investigate resistance response of several introduced varieties against ScSMV in a glasshouse condition and the impact of the viral infection on chlorophyll and proline content in sugarcane leaves.  Sugarcane plants were inoculated using ScSMV inoculum one month after planting using an abrasive pad rubbing method. Disease incidence and severity was observed at week 4-12 after inoculation and variety resistance levels were classified based on disease incidence. Confirmation of the virus was done by RT-PCR. Spectrophotometer was used to measure chlorophyll content at dual wavelengths of 645 and 663 nm, and proline content at wavelengths of 520 nm. The results showed that most of the tested varieties were susceptible to ScSMV. There are six highly resistant varieties, namely SRA 1, SRA 2, N 10-4, N 10-7, N10-9, and N 10-13, but these varieties still require to be tested on a field scale. ScSMV infection generally decrease chlorophyll and proline content. However, the physiological effect of ScSMV infection on chlorophyll and proline content needs further investigation.

Penyakit busuk akar dan pangkal batang pada tebu merupakan penyakit yang memiliki arti penting secara ekonomi.  Salah satu agen hayati yang berpotensi mengendalikan penyakit busuk akar dan pangkal batang Xylaria adalah Trichoderma sp. Isolat T10 ISRI memiliki aktivitas enzim kitinase yang tinggi sehingga dapat digunakan sebagai agen hayati. Identifikasi isolate T10 ISRI bertujuan agar potensi lain dari isolate T10 ISRI dapat diktahui. Tujuan dari penelitian ini adalah untuk mengidentifikasi isolat T10 ISRI sampai dengan tingkat spesies melalui identifikasi secara molekuler. Metode identifikasi dilakukan dengan sequencing DNA melalui BLAST dan pembuatan pohon filogenik. Hasil penelitian menunjukkan bahwa spesies isolat T10 ISRI yaitu Trichoderma asperellum dengan kesamaan 100% dengan strain Trichoderma asperellum T sum 66 dari data NCBI dan kedekatan dalam kelompok 0,00001 dari pada jarak diluar kelompok yaitu 0,3287.