Rusmilah Suseno

Deteksi dan Kajian Kisaran Inang Virus Penyebab Penyakit Daun Keriting Kuning Cabai

High incidence of Pepper yellow leaf curl virus (PepYLCV) was observed in Indonesia since early 2000. Disease incidence in Yogyakarta, Central and West Java reached 100% on Capsicum frutescens, but only 10-35% on C. annuum. As an exception, the disease incidence on C. annuum cv. TM 999 was in the range of 70-100%. The causal agent of the disease, PepYLCV, was detected by polymerase chain reaction. Viral specific DNA fragment of the size ~1600 bp and ~550 bp was amplified from infected plants using two pairs of geminivirus universal primers pAL1v1978/pAL1c715, and pAv494/pAc1048, respectively. The PepYLCV has an intermediate host range including plants belonging to the family of Solanaceae, Leguminosae, and Compositae. The species belonging to the families of Cucurbitaceae, Malvaceae, Chenopodiaceae, and Amaranthaceae were resistant to the virus. Physalis floridana, is very prospective as a propagation host for the geminivirus infecting pepper. Nicotiana spp., cucumber, watermelon, cotton, and Sida sp. could be used as a differential host. Besides, Capsicum frutescens cv. Cakra, tomato, N. benthamiana, N. glutinosa, and Ageratum conyzoides could be used as indicator plants for the geminivirus infecting pepper.

Detection and Host Range Study of Virus Associated with Pepper Yellow Leaf Curl Disease

Rojolele is one of Indonesian local variety from Javanica group that susceptible to yellow stem borer (Scirpophaga incertulas). Previous study showed that Rojolele can be cultured and regenerated in vitro. Two cry genes, cryIB-cryIAa were fused and introduced into rice cv. Rojolele in an attempt to improve resistance and to obtain durable resistance rice against the yellow stem borer. Two-week old embryogenic calli of Rojolele rice were inoculated with Agrobacterium tumefaciens harbored with binary vector pCAMBIA 1301, 1303, or 1304 carrying cryIB-cryIAa hybrid gene, hygromycin resistant gene (hpt), and -glucuronidase (gus) gene interrupted with an intron. The transformed calli were selected gradually on medium containing hygromycin (50, 100 mg/l) and regenerated on medium containing 0.5 mg/l IAA and 0.3 mg/l BAP. GUS activity in infected calli was detected by histochemical assay 3 days after inoculation. The highest (100%) transformation efficiency were obtained from calli transformed with pCAMBIA 1303 and 1304. Thirty four out of 77 transformed shoots were tested positive for the cryIB-cryIAa gene using PCR analysis. These shoots were grown in the soil to maturity and to collect the seeds. PCR analysis of the T1 progeny revealed that two out of six lines tested showed a Mendelian segregation pattern. These two lines were also potentially resistant to yellow stem borer based on bioassay in planta. Key words: cryIB-cryIAa hybrid gene, yellow stem borerRojolele is one of Indonesian local variety from Javanica group that susceptible to yellow stem borer (Scirpophaga incertulas). Previous study showed that Rojolele can be cultured and regenerated in vitro. Two cry genes, cryIB-cryIAa were fused and introduced into rice cv. Rojolele in an attempt to improve resistance and to obtain durable resistance rice against the yellow stem borer. Two-week old embryogenic calli of Rojolele rice were inoculated with Agrobacterium tumefaciens harbored with binary vector pCAMBIA 1301, 1303, or 1304 carrying cryIB-cryIAa hybrid gene, hygromycin resistant gene (hpt), and -glucuronidase (gus) gene interrupted with an intron. The transformed calli were selected gradually on medium containing hygromycin (50, 100 mg/l) and regenerated on medium containing 0.5 mg/l IAA and 0.3 mg/l BAP. GUS activity in infected calli was detected by histochemical assay 3 days after inoculation. The highest (100%) transformation efficiency were obtained from calli transformed with pCAMBIA 1303 and 1304. Thirty four out of 77 transformed shoots were tested positive for the cryIB-cryIAa gene using PCR analysis. These shoots were grown in the soil to maturity and to collect the seeds. PCR analysis of the T1 progeny revealed that two out of six lines tested showed a Mendelian segregation pattern. These two lines were also potentially resistant to yellow stem borer based on bioassay in planta. Key words: cryIB-cryIAa hybrid gene, yellow stem borer

Deteksi Begomovirus pada Cabai Secara Cepat melalui Isolasi Genom DNA

Pepper yellow leaf culr disease has been widely spreading in Indonesia, especially in Special Province of Yogyakarta and Central Java since 2000. The disease is difficult to control because its fast spreading over in the field by the vector. To prevent epidemic of the disease, early detection method of the causal agent is needed. The aim of the research was to detect the causal agent of the pepper yellow leaf curl disease by isolating the DNA genome. Using the Guanidine-alkaline method, two specific fragments of the DNA were produced approximately at 2600 bp and 1600 bp. The DNA fragments were similar with the DNA genome of Begomovirus. The method applied in this study is faster and easier for early detection of the Begomovirus in infected crop than detection by the Polymerase chain reaction (PCR).