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The purpose of this study was to determine the effect of cobalt-60 gamma ray irradiation which could expand the genetic security of white taro cultivars (Xhanthosoma sagittifolium (L)). This research has been carried out in

Taro plants have long been cultivated and utilized as a source of additional food in Indonesia. Besides being a source of food, taro can also be used for industrial purposes, such as cosmetic and plastic raw materials. Taro tuber characteristics determine its use. Research in the form of a survey conducted in 2016, by observing and studying the morphological characteristics of Taro, in three Districts in West Sumatra Province. The research objective is to obtain information on Taro plants that have the potential to be made as carbohydrates in supporting food security and diversification as well as providing with initial information on Taro germplasm. To see the level of plant relatedness, NTSYS program version 2.1 was applied. Results of the study managed to collect 47 accessions, with differences in diversity between locations, and of that number, based on morphological characters of tubers observed, there were 32 accessions that have the potential to serve as a source of carbohydrate. Research is still ongoing to test the properties of carbohydrates and analysis of genetic variability.

The use of microbial inoculants as biofertilizers and/or antagonists of phytopathogens provides a promising alternative to chemical fertilizers and pesticides. Cyanobacteria are a remarkable group of prokaryotes, which are known to exist independently and in symbiotic/facultative associations with a diverse range of members of the plant. Cyanobacteria inoculation had been reported to enhance the growth, nitrogen fixation and yields. Although, their establishment and role in plant growth promotion and biocontrol activity is poorly known. This research purposed to isolate and screen the best indigenous cyanobacteria from chili rhizosphere to promote growth rate and control R. syzygii subsp. indonesiensis on chili. The study consisted of three parts: (i) isolation and multiplication of the cyanobacteria from soil rhizosphere, and screening through Hypersensitive response (HR) on Mirabilis jalapa for pathogenicity test, (ii) in planta screening of selected cyanobacteria isolates (from second's step) to increase growth of chili seedlings, and (iv) in planta evaluation of selected cyanobacteria isolates for the control of bacterial wilt disease and promote growth of chili. Cyanobacteria isolated with BG-11 medium and incubated in room temperature with 12/12 h light/dark cycle. 49 cyanobacteria had isolated from chili rhizosphere. All isolates also showed suppression of disease development caused by R. syzygii subsp. indonesiensis. BCBY 3.1.3, and CBY 5.1 showed suppression of symptom appear (60.00 day post inoculation (dpi) compared to control (.38.667 dpi) and also suppressed disease severity (1.67) compared to control (3.00). The two strains which have best ability to increased growth rate also have best ability to fully suppressed disease development with no symptom appear until last day of observation.

Cotyledon, leaf, root and hipokotyl explants of Sesbania grandiflora were excised from germinated seedlings and cultured on Murashige & Skoog's basal medium supplemented with various combinations of cytokinin and auxin. Both cytokinin and auksin were required for induction of shoot. Medium of shoots induction has observed on MS medium supplement with BAP 1 mg/l and NAA 0.08 mg/l. On this medium, 66.7 % cultures responded with an average number of 1.7 shoots per explant cotiledon. However, the average shoot length was limited to 0.7. whereas shoots induction obtained on MS medium with addition 1 mg/l BAP and 0.08 mg/l NAA average shoot length 0.5 cm. 50 % cultur responded with an average number of 1 shoots per explant.