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To increase the efficiency of crop production from Dendrobium phalaenopsis orchids, mass propagation has been performed by inducing somatic embryogenesis through Agrobacterium-mediated transformation of the Arabidopsis embryo gene AtRKD4 into orchid protocorm (developing orchid embryo). The three-week-old protocorms of D. phalaenopsis were genetically transformed with T-DNA carrying 35S :: GAL4 :: AtRKD4 :: GR through A. tumefaciens strain EHA 105. The cultures were maintained in VW medium with 10 mg L-1 Hygromycin. Due to the existence of glucocorticoid response element (GR) in the T-DNA construct, the transformed protocorms were transferred into VW medium with the addition of 15 µM Dexamethasone in 6 weeks after transformation to activate the transgene. A total of 12% protocorms has been confirmed for Hyg + by using PCR. The expression of embryo gene AtRKD4 was confirmed by cDNA analysis using AtRKD4 specific primers and Actin primers as a positive control experiment. The expression level of AtRKD4 in 2.5-month-old D. phalaenopsis transformant shoots was 7 times higher than nontransformant plants, and increased to 86 times higher in 8-months, that much higher than that of non-transformant. These results provide an improved method for genetic transformation of D. Phalaenopsis and will (eventually) increase production efficiency in the future.

Chlorophyll is a pigment of photosynthesis which is also efficacious as a cure for brain, lung, and oral cancer, and can be used as a disinfectant, antibiotic and dietary supplement, while carotenoids are useful as antioxidants. The content of the two pigments is strongly influenced by the age of the plant, especially for vegetable crops used in leaves such as cowpea (Vigna unguiculata (L.) Walp.). The purpose of this research is to know the pattern of chlorophyll content and carotenoid of cowpea leaf during the growth phase and to know the age of the right plant for harvesting cowpea so that the highest chlorophyll and carotenoid content is obtained. Cowpea seeds obtained from seeds are added then planted in pots containing ready-made planting media in the greenhouse. Chlorophyll and carotenoid analyzes were performed at different plant ages from 1 to 11 weeks. The research design used is Completely Randomized Design. Data were analyzed using variance analysis and continued with Duncan test at 95% significance level. The results showed that the highest chlorophyll and carotenoid content was produced by the cowpea leaf in the vegetative phase or before the flowering time. The highest chlorophyll content was obtained at 4WAP (weeks after planting) of age crop, while the highest carotenoid content was obtained in 3WAP.

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