Pendugaan Tindak Gen Ketahanan Terhadap Virus Tungro Pada Varietas Padi (Gene Action Estimation of Resistance Gene to Tungro Virus Disease on Rice)

The objective of the study is to estimate the gene action of resistance gen to rice tungro virus disease. For the purpose, three parental line i.e. Seratus Hari T-36 (resistant), Utri Merah-1 (resistant), and Cisadane (susceptible) were crossed without resiprocal to produce F1, F2, BC1, and BC2. Population (P1, P2, F1, F2, BC1, and BC2) from all crosses were inoculated with tungro virus by infected green leafhopper at 14 days after seedling. The the were grown in endemic area at Tanjung-siang, Subang, West Java. Observed characteristic was visual symptons using resistant scoring according to Hasanudin et al. (1988) and absorbent value using ELISA test according to Koenig methode (1981). The result showed that scoring index of Seratus Hari T-36 X Cisadane and Seratus Hari T-36 x Utri Merah-1 crosses adecuately correspond to additive-dominance model with significantly additive effect. Utri Merah-1 X Cisadane cross adequately correspond to epistatic model. Dominance effect was found on Seratus Hri T-36 X Cisadane cross. The absorbent value result of Seratus Hari T-36 X Cisadane and Utri Merah-1 X Cisadane crosses showed the same conclusion with resistance scoring index. Keywords : rice, tungro virus, gene action, resistanc