Inheritance CsNitr1-L Gene in Transgenic Rice Plants Ciherang Generation of BC3F4

Abstract

Efforts to increase rice production today meet some constraints, such as lans use conversion, climate change and degradation of quality of land affecting the productivity. Farmers provide additional chemical fertilizer to increase rice productivity especially nitrogen fertilizer. Field conditions with submarging system for rice plant can result in the loss of nitrogen fertilizer due to dissolve, evaporate and undergo denitrification, so most of the amount of nitrogen fertilizer applied in rice fields can not be optimally absorbed by plants. Nitr1-L gene is a gene that encode nitrites transporter which is included in the group of proton oligopeptide transporter (POT), so the absorption of nitrites by the plants containing this transporter becomes efficient. The gene encoding this protein (CsNitr1-L) under the control of 35S CaMV promoter had been introduced into rice plants (Oriza sativa L.) subspecies Japonica cv. Nipponbare. To transfer this gene, the japonica transgenic rice had been crossed with Indica rice cv. Ciherang, followed by back-cross and self pollination until BC3F4 generation. The aim of this study was to analyse introgression of CsNitr1-L gene in the transgenic rice BC3F4 generation. The transgenic rice plants in BC3F4 generation were selected based on the resistance to hygromicin. More than 90% population of BC3F4 are putatively transgenic rice plants. These transgenic plants were confirmed by PCR analysis by using primers corresponding to hpt gene. The seed productivity of transgenic lines was higher than that of nontransgenic ones. Based on the highest productivity of every transgenic line of G3, G7, G8, G11, four transgenic plants were analysed by PCR. PCR analysis showed that these four transgenic plants contained CsNitr1-L under the control of 35S CaMV promoter. The result indicated that the transgene of CsNitr1-L was introgressed into BC3F4 generation.