Drought and submergence are the two major limiting factors that reduce rice production. In this study, the relevance of yield traits through path analysis under drought and submergence conditions to improve grain yield of rice, from dry season 2014-2015 and genotypic analysis using SSR markers was evaluated, during 2015-2016. Path analysis indicated that the number of panicles/clusters had the highest and a direct positive effect on the grain yield, followed by the number of filled-grain/panicle, and the harvest index compared to other component traits. These traits could be used as selection criteria for high yield and drought tolerance in populations of rice. There were two markers including RM201 (210-225 bp) and RM219 (210-215 bp) chosen to select parents in backcrossing because production of polymorphic bands relevant to submergence and drought tolerance genes. By the BC 1 F 1 and BC 2 F 1 generations of the cross OM6162/Swarnasub1//OM6162, primers RM201 and RM219 were identified drought and submergence tolerant individuals. These lines will be used in breeding programme for release of both drought and submergence tolerant with considerable yield in next step. Findings of this study are promising to develop rice cultivars tolerant to both drought and submergence, and may therefore help to reduce detrimental impacts from climate changes to rice production.

The Trichoderma asperellum T10 isolated from soil for dragon fruit growth in Binh Thuan province, has a strong antagonistic ability against the Neoscytalidium dimidiatum, causing the white spot disease on dragon fruit. The results showed that T. asperellum T10 had a high antagonistic effect against fungal pathogens of 100%, and the inhibitory zone diameterreached 28.00 mm in laboratory conditions. T. asperellum T10 has been influential in the prevention and treatment of white spot disease in greenhouse conditions and reducing disease rates by 28-40% and disease index by 23-33% compared to the control. T. asperellum T10 is proposed as a potential strain of a microbial product for the prevention and treatment of white spot disease on dragon fruit.

Anthracnose is one of the serious diseases on coffee trees. Prevention of coffee berry disease on coffee trees by biological measures is an alternative solution to the use of chemical pesticides. The study aims to select strains of Streptomycesand Trichoderma with strong antagonistic ability against Colletotrichum sp. CC1.5 fungus causing coffee berry disease. Results revealed that an actinomycete strain DR92S showed a high ability to antagonize Colletotrichum sp. CC1.5 after 8 days by direct antagonism and diffusion through agar holes, with the antagonism efficiency and inhibition zone of 71.85% and 28.63 mm, respectively. A strain of Trichoderma DR10T8 showed 100% inhibitory effects against Colletotrichum sp. CC1.5 after 5 days of treatment. The gene sequence analyses exhibited that the closest genetic relationships of the actinomycete strain DR9S2 and the fungal strain DR10T8 were Streptomyces hiroshimensis and Trichoderma viride, respectively.

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