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Effectiveness of the application of organic matter and Trichoderma viride from suppresive soil to control fusarium wilt on banana plant. Fusarium wilt disease caused by Fusarium oxysporum f.sp. cubense is one of the problems in banana production. This research was aimed to evaluate the effect of Trichoderma viride isolated from suppresive soil and organic matter on controlling fusarium wilt on banana plant. The efficcacy trial consisted of 12 treatments and four replications within each treatment. Each experimental unit consisted of 10 plants. Organic matters used were rice straw, cassava peel, and compost. Treatments were arranged in a randomized complete block design. Data obtained were analyzed by analysis of variance followed by orthogonal analysis (P≤0.05). Application of T. viride suppressed disease incident up to 65%. The highest disease incident occurred in plants treated without T. viride and organic matter and in plants treated with organic matter only (78.33%). Disease incidence in plants treated with T.viride was lower than those treated with the combination of T. viride and organic matter. Different application times (in nursery or soil medium) did not significantly affect fusarium wilt incidence. The type of organic matter did not significantly affect the incidence and severity of fusarium wilt.

This research aimed to study effects of IBA, NAA and their combination on rooting and shoot sprouting in Malay apple cuttings. Cuttings from superior genotype were collected and treated with (in ppm w/w): 0, 2000 IBA, 4000 IBA, 2000 NAA, 4000 NAA, 1000 IBA+1000 NAA, 2000 IBA+2000 NAA. To record the timing and percentage of rooting, cuttings were treated with (in ppm w/w) 1000 IBA+1000 NAA or without auxin as control. The results revealed that application of auxin was significantly enhanced root formation as shown by the significant increases in rooting percentage and number of roots. NAA at 2000 or 4000 ppm was the most effective auxin to promote root formation (100 %, 17.8–25.5 roots per cuttings), followed by NAA+IBA (100 %, 16.8– 9.8 roots per cuttings) and the least effective was IBA alone (79-100 %, 3.2–7.1 roots per cutting). The best treatment for rooting and shoot sprouting were (in ppm) 1000 IBA+1000 NAA, since it produced higher root length, better root morphology and higher shoot sprouting. It was also found that a combination of IBA+NAA each at 1000 ppm not only enhanced root percentage, but also shortened the time for root formation.

This experiment was conducted to reveal genetic diversity among 38 genotypes of sugarcane (Saccharum officinarum L.) using RAPD markers. The population consisted of 8 genotypes from Australia, 7 from Africa, 10 from America, and 13 from Asia. Genetic similarity was ranging from 17% to 97% , with the average of 57%. UPGMA dendrograms divided the population into three major groups i.e. group 1, 2, and 3 which consisted of 23, 10, and 5 genotypes, respectively. Each major group comprised genotypes of different geographical origins. The dendrogram divided each group into some subgroups. There were 8 subgroups i.e. 4 subgroups in group 1, 2 subgroups in group 2, and 2 subgroups in group 3. Some genotypes of same geographical origin were clustered into in at least 3 different subgroups, meaning that they were genetically dissimilar. On the other hand, some other genotypes of different geographical origin were clustered into the same subgroup, meaning that they were genetically similar. This data would help sugarcane breeders to select parents for hybridization in order to maximize heterosis. This could be conducted by selecting parents of dissimilar genotypes.

Peanut somaclonal variants resistant to Sclerotium rolfsii derived from in vitro selection with fungal culture filtrates. Sclerotium stem rot is one of the most important peanut disease which often caused significant yield loss. The use of peanut cultivars resistant to Sclerotium rolfsii infection is the most efficient way to control the disease. Attempts to obtain peanut lines with tolerance or resistance to Sclerotium stem rot through induction of somaclonal variation and in vitro selection using fungal culture filtrates (CF) have been conducted previously. Somatic embryo (SE) clumps that had been maitained in culture for approximately one year in regeneration medium were exposed onto selective medium containing 30% S. rolfsii CF for three consecutive 1 month –passages, and the SE formed after selection periods were considered to be insensitive to the fungal CF. A number R0 peanut lines have been regenerated from CF-insensitive SE, and their R1 and R2 progenies were grown in a plastic house for evaluation on qualitative and quantitative variant characters. Early identification for tolerance to S. rolfsii was also conducted among R0 peanut lines, and the results have shown enhanced resistance when compared to the original non-selected cultivar. However, further evaluation is needed to study responses of the R1 and R2 progenies of the somaclones against S. rolfsii infection. The objective of this particular study was to evaluate responses of R1 and R2 peanut somaclones derived from fungal CF-insensitif SE against S. rolfsii infection in the plastic house. Results of this experiment showed, a number of resistant somaclonal variants were obtained among R1 and R2 population, which segregated as resistance and susceptible to S. rolfsii infection. The resistance somaclonal variants initially showed stem rot symptoms after inoculation with S. rolfsii with disease score (DS) of 1 to 3. However, as the plants grew and developed, they showed wound-healing process at the lesio and they were able to produce the same or higher number of filled pod as the original non-inoculated peanut plants.

The aim of this study was to observe responses of two banana cultivars ‘Ambon’ and ‘Raja Bulu’ on different BA concentrations and effects of different media and fertilizer on survival and growth of plantlets. Sterilized explants were cultured on initiation medium (MS with 1mg L -1 BA) for 4 weeks, then subjected to media MS with 2.5, 5.0, or 7.5 mg L -1 BA. Numbers of shoot buds, shoots and propagules were recorded after 4 consecutive passages with 4 weeks intervals. Rooted plantlets were acclimatized in three different media, then treated with or without NPK (32:10:10) fertilizer solution once a week. After 2 months, the survival and growth of plantlets were recorded. Cultures of banana ‘Ambon Kuning’ showed higher regenerative capacity compared to ‘Raja Bulu’, producing higher numbers of shoot buds, shoots and propagules. The best medium for propagule proliferation of both banana cultivars was MS+5 mg L -1 BA, producing 40.7 propagules for ‘Ambon Kuning’, and 12.3 propagules for ‘Raja Bulu’ per explant. In all acclimatization media tested, 100% of plantlet survival was achieved. The best plantlet growth was found in sand: compost (1:1,v/v) with application of NPK solutions. The in vitro -derived plants were planted in the field and produced fruits of high quality.

Early Identification of Sclerotium rolfsii Resistant Lines of Peanut Derived from In Vitro Selection Using S. rolfsii Culture Filtrates. The objectives of this experiment was to evaluate methods for early identification of Sclerotium rolfsii resistant lines derived from fungal culture filtrate (CF)-insensitive somatic embryos (SE) and to correlate the results of early identification with that of direct S. rolfsii inoculation in the plastic house. In the first method, shoots regenerated from CF-insensitive SE were planted onto selective medium containing 30% of S. rolfsii CF for one month and then responses were evaluated. In the second method, leaves and leaflets of R0 peanut lines derived from CF-insensitive SE were inoculated with S. rolfsii by detached leaf-dual culture test. The damages of the inoculated leaves and leaflets were assessed 6 days after inoculation. A number of R1 plants were grown in the plastic house from seeds harvested from R0 peanut lines, and they were inoculated with S. rolfsii at 30 days after planting (dap). Responses of the inoculated R1 plants were observed at 44 dap. Results of the experiment indicated that shoots from CF-insensitive SE showed less damage scores (DS=1.2), when cultured on CF-containing selective medium than ones from non-selected SE (DS=2.9). Most of the detached leaves and leaflets inoculated with S. rolfsii totally necrosed. However, leaves and leaflets from 7 out of 23 R0 lines showed variegation between necrosed and healthy tissues, indicating the presence of S. rolfsii resistant tissue among the tested leaves and leaflets. Direct inoculation of R1 plants in the plastic house showed 10 out of 18 progenies derived from 6 R0 lines showed less disease severity scores (DSS=2 or 3) and they were able to survive and produce seeds. On the other hand, seed derived (original) peanut plants cv. Kelinci inoculated with S. rolfsii all showed DSS=5 and died after inoculation. The overall results of the experiment indicated the usefullness of in vitro selection using S. rolfsii culture filtrates for regenerating S. rolfsii resistant peanut variants and the possible use of methods for early identification of desirable variants.