Sriani Sujiprihati

Infeksi Cucumber Mosaic Virus dan Chili Veinal Mottle Virus terhadap Pertumbuhan dan Hasil Tanaman Cabai

A research was undergone to study the effect of single and double infection of Cucumber Mosaic Virus (CMV) and Chili Veinal Mottle Virus (ChiVMV) on the growth and yield of five chilli cultivars, i.e. Prabu, Taro, Jatilaba, Laris, and Keriting Bogor. Mechanical inoculation was conducted to transmit the virus. Infection of the virus was then confirmed with DAS-ELISA. Severe symptom was observed on plant given double infection compared to those given single infection. The rate of plant growth and the amount and weight of fruits were reduced. The type of interaction between CMV and ChiVMV on most chilli cultivar can be considered as interference and additive. Synergism interaction was only observed on cultivar Laris. Based on symptom expression and reduction on yield, it can be concluded that all chilli cultivars used in this study could not hold up the virus infection.

Kajian Plant Growth Promoting Rhizobacteria sebagai Agens Proteksi Cucumber Mosaic Virus dan Chilli Veinal Mottle Virus pada Cabai

This study was conducted to evaluate the effectiveness of plant growth promoting rhizobacteria (PGPR) in protecting chillipepper plant from infection of cucumber mosaic virus (CMV) and chilli veinal mottle virus (ChiVMV). Seven isolates of PGPR, i.e. BC1, BTP2H, BTP3G, BTP3O BTP1, BTP2D, and T1F were applied as seed treatment and soil drench. Plants height, number of branch, and fruits weight were measured every one and ten weeks after virus inoculation. Virus concentration in plants and disease incidence were confirmed by enzyme-linked immunosorbant assay (ELISA). Results showed that inoculation with PGPR improved the seed germination. Eight days after sowing, the percentage of PGPR treated seed germination reached 50-84%; whereas those of untreated seed reached only 18%. In general, PGPR treatment significantly reduced (p < 0.05) the effect of virus infection on plant growth. Two PGPR isolates, i.e. BTP1 and BTP2H, maintained fruit weight of infected plants as good as those of healthy plants. Based on ELISA, PGPR was able to inhibit the disease incidence. The BTP3O and BTP2D isolates even protected the plant from ChiVMV infection. Concentration of salicylic acid and peroxidase were relatively higher on plants treated with PGPR than those without PGPR treatment. This gave an indication that PGPR may act as induction agents for systemic acquired resistance. Therefore, PGPR treatment is a promising strategy to control viral diseases on chillipepper.

Penyisipan Gen OsDREB1A pada Tanaman Padi untuk Regenerasi Sifat Toleran Kekeringan

Seed of the rice hybrid generally is not fully filled, resulting in low seed quality. Study was conducted in 2009 at the Indonesian Centre for Rice Research, Sukamandi, aiming to determine the effect of seed invigoration methods on viability and vigor of hybrid rice seeds. The treatments consisted of two factors, namely: (A) initial quality of Hipa 5 seeds, i.e., low and moderate, and (B) 8 seed invigoration methods, i.e., no treatment (control); soaking in water for 48 hours; soaking in 1.0 Mpa PEG 6000 solution for 24 hours; soaking in 5 ppm GA3 solution for 24 hours; soaking in 10 ppm GA3 solution for 24 hours; 12 hours hardening, 24 hours hardening), and soaking in a solution mixture of GA3 10 ppm Kinetin + 15 ppm for 24 hours. The results showed that all seed invigoration treatments increased seed germinations by 1 to 8% and the seed growth rates by 0.7 to 4.3 %/24 hour in seeds of hybrid rice Hipa 5, either in the high initial quality seeds or in the low initial quality seeds. Soaking of the medium quality seeds in 10 ppm GA3 + 15 ppm kinetin solution resulted in the highest seed germination (89%). In the low quality seeds, treatments with GA3 and 15 ppm Kinetin also resulted in high seed germination (79%), equivalent to that of treatment with 24 hours hardening (78%). All seed invigoration treatments, except for soaking in water for 48 hours, increased length and dry weight of the seedling stem. The highest length of the stem was shown from seed soaked in 10 ppm GA3 solution (16.8 cm), whereas the highest stem dry weight was shown from seed soaked in a mixture of 10 ppm GA3 + kinetin 15 ppm solution (526 mg/seedling). Based on all variables evaluated, soaking seeds in 10 ppm GA3 solution or a mixed solution of 10 ppm GA3 + kinetin 15 ppm is considered effective invigoration treatment to improve vigor and growth of hybrid rice seeds.A research was conducted to determine the response of introduced hybrid rice varieties to bacterial leaf blight (BLB) disease caused by Xanthomonas oryzae pv. oryzae (Xoo) and its relationship to grain yields The trial was planted at the Sukamandi Experiment Station during the wet season (WS) 2008/09 and at Kuningan Experiment Station in the dry season (DS) of 2008 and WS 2008/09. Fourteen rice genotypes consisting of 9 introduced hybrid rice varieties from China, variety Code (resistant check), IR64 (susceptible check), and Intani-2 Batang Samo (hybrid checks), and Ciherang (inbred check) were evaluated. The experiment was laid out in a completely randomized block design with three replications. The trial at Kuningan, a BLB endemic area, was carried out with an assumption that grain yield performances of the 14 rice genotypes would be influenced by be severity of the BLB. Data from the greenhouse trial showed that reactions of the introduced hybrid rice to Xoo pathotype III varied from moderately resistant to resistant, moderately susceptible to susceptible to Xoo pathotype IV, and resistant to moderately Xoo pathotype VIII. In the field, the severity of the BLB disease ranged from 4.2% on Sembada B9 to 11.4% on WCR115 in the DS 2008, and from 4.9% on Sembada B9 to 30.4% on WCR073 in the WS 2008/09. In the DS 2008, the highest grain yield was obtained from Sembada B9 (9.79 t/ha) followed by Sembada B8 (9.6 t/ha), Sembada B3 (9.26 t/ha), and Sembada B5 (9.79 t/ha). In the WS 2008/2009, the highest grain yield was also obtained from Sembada B9 (8.85 t/ha) followed by Sembada B8 (8.80 t/ha), Sembada B3 8.63 t/ha), and Sembada B5 (7.77 t/ha). These four rice hybrids were resistant to Xoo pathotype III. The overall average rice yield in the DS, was higher than that in the WS 2008/2009, presumably as a result of the lower severity BLB disease.Tungro is the most important viral disease of rice plant, caused by two types of viruses, namely Rice Tungro Bacilliform Virus (RTBV) and Rice Tungro Spherical Virus (RTSV), transmitted by green leafhopper Nephotettix virescens. Planting resistant varieties proved effective in preventing the occurrence of tungro disease explosion, but the availability of tungro virus resistant varieties are still limited. To determine the best breeding strategy, genetic inheritance model for resistance to tungro disease needs to be studied especially the gene action and the number of genes controlling resistance. For this study, variety TN1 was crossed with OBSTG02-28 to produce F1, F1R, BC1-1, BC1-2, and F2. All crosses were inoculated with tungro virus and visual symptoms of the disease were observed, followed with the ELISA test. Scoring of the disease and ELISA test showed that the resistance of OBSTG02-28 was controlled by two complementary genes with a ratio of 9:7. The additive-dominant of gene action model fitted for the inheritance of resistant gene with additive gene action. The narrow sense heritability was considered high; therefore, selection for gene resistance to tungro disease could be conducted in the early generations.Aromatic rice such as Basmati and Jasmine has a high economic value in the world market. This study aimed to identify characteristics and grain quality of eight aromatic rice varieties grown at locations with different altitudes. The aromatic rice varieties were Basmati 370, originated from the International Rice Research Institute (Basmati 370 IRRI), India (Basmati 370 India), collection of Indonesian Rice Research Institute Sukamandi (Basmati 370 Sukamandi), HSPR, Khao Dawk Mali (KDM/Jasmine), Milky rice, local variety Mentik Wangi, and Sintanur. The experiment was planted in 8 locations, namely in Klaten, Pasarmiring, and Bajeng (altitude 800 m asl). Results showed that the best quality of milled rice was obtained from aromatic rice grown at altitudes of 500 to 800 m asl., of which the introduced aromatic rice (Basmati, KDM/Jasmine, and HSPR) and the local aromatic rice varieties (Milky rice and Mentik wangi) yielded the highest, based on percentages of milled rice and head rice and the lowest percentages of broken and cracked rice grains. The best grain milling quality of Sintanur variety (percentage of milled rice and head rice yield) was obtained when it was planted at high altitude (>800 m asl).Fertilizers play important roles in increasing rice yield. Government policy in a form of determined Highest Retail Price (HRP) of urea and the Government Purchasing Price (GPP) of rice grains not always been effective, so that farmers might not rationally use the fertilizers. Assessment the effectiveness of policy on the implementation HRP and GPP was conducted in five provinces, with different agro-ecosystem. The assessment used primary data collected in 2008, with aim to analyze the effectiveness of the policy implementation on urea HRP and on rice grains GPP. Assessment locations at the provincial and regency levels were determined based on a purposive sampling technique, whereas assessment locations at the district to village levels were selected based on the production center, determined by the multistages random sampling. Data collection of input and output prices were done through surveys using structured questionnaires to kiosks of farm inputs at the village level, the Village Cooperative Units (KUD), and other relevant agencies. Results of the assessments indicated that policy on HRP of urea fertilizer was not effectively complied, especially in the irrigated land with a high-low tidal agro-ecosystem. The GPP policy implementation was quite effective; in the aggregate, the most effective implementation of the policy was on the irrigated lands. The highest level of farmers’ ability to buy urea fertilizer (IHKD) was on the irrigated land. The urea HRP policy is expected to go along with the increase of grain GPP.Rice as staple food is consumed as a source of energy and protein, but also contains minerals and vitamins. This study was aimed to obtain information on mineral contents of rice lines obtained from the bio-fortification program. The research was conducted at the Experiment Farm of the Rice Research Installation Sukamandi, during Wet Season of 2007/2008. A total of 26 rice varieties/lines with high yielding potential and high Fe and Zn contents in the grain were planted in 4 m x 5 m experimental plots with a spacing of 25 cm x 25 cm. The experiments were arranged in a randomized block design with three replications. Samples of grain harvested from each plot were milled using a Satake mini grinder that produces milled rice with an 80% milling degree. Analysis of the mineral content of rice from the varieties/lines was tested using an ICP (Inductivity Couple Plasma) at the Waite Analytical Service Laboratory, University of Adelaide, Australia. The results indicated a wide diversity in the mineral contents (Ca, P, Mg, Na, K, S, Fe, Zn, and Mn) of the milled rice of the tested rice varieties/lines. Six lines produced milled rice rich in macro minerals (Ca, P, and K) and have a potential to be released as varieties with high macro mineral contents. Seven other rice lines produced high levels of Fe and Zn and are recommended as candidate for high yielding rice varieties with high micro mineral contents.Pests and diseases cause significant rice yield losses every planting season. One of the important rice disease is tungro, a virus disease transmitted by green leafhoppers (Nephotettix virescens Distant), that can cause yield losses of up to 90%. This study was aimed to determine the effectiveness of entomopathogenic fungi Verticillium lecanii and Beauveria bassiana to control N. virescens as a vector of the tungro virus. The experiment was arranged in a randomized complete block design with two factors. The first factor was conidial density of the fungi and the second factor was period of food acquisition. The variables observed were mortality and the ability to fly of N. virescens at 3, 7, 10, and 14 days after application (DAA), tungro disease symptoms, virus incubation periods, disease incidences, plant heights, and number of tillers. The results showed that applications of B. bassiana (107 conidia/ml) and V. lecanii (108 conidia/ml) caused death of green leafhoppers within 3-14 DAA. Based on the virus incubation period and the incidence of the tungro disease, application of the entomopathogenic fungi did not affect the ability of N. virescens to transmit tungro virus.

Cucumber Mosaic Virus and Chili Veinal Mottle Virus Infection on Growth and Yield Component of Chilli

The term of allelopathy refers to chemical interactions (inhibitory or stimulatory) between plants, between plants and microorganisms, and between microorganisms. The wealth of information on the processes, procedures, and practices of allelopathy has contributed to understanding this field of science. Recently, researches of allelopathy have been conducted in laboratory, greenhouse, and field with multifaceted standpoint in some concerning area: (i) allelochemicals identifications and screening test; (ii) ecological and physiological aspects of allelopathy; (iii) genetic studies and the possibilities of using plant breeding or genetic manipulation to enhance allelopathic varieties; (iv) the use of allelopathic potential in the biological control, including as natural pesticide, of weeds and plant diseases as eco-friendly approach for sustainable agriculture scheme. Key words: Allelochemicals, biological control, sustainable agriculture

Evaluation of Plant Growth Promoting Rhizobacteria as a Protecting Agent Against Cucumber Mosaic Virus and Chilli Veinal Mottle Virus on Chillipepper

A number of abiotic stress responsive genes have been identified from various plant species through reverse genetic strategy. A group of genes are involved in plant responses to stress; they are activated by diverse stress conditions and through different mechanisms. One single gene can be induced by several different stress factors; on the other hand, a number of genes can be up-regulated by a single factor. In Physcomitrella patens, through Northern hybridization, the transcript level of the gene GFDD4-I was detected to be markedly increased by ABA, dehydration and cold, but not by salinity and osmotic stress. In Arabidopsis thaliana, a homologous gene to GFDD4-1 namely At2g47770, was confirmed to fulfill similar function as in P. patens: it is inducible by various abiotic stress treatments, i.e. ABA, dehydration, salinity, and cold. Inducible genes in response to abiotic stress factors may be responsible for plant tolerance to those factors.