Biomass accumulation and cell wall structure of rice plants overexpressing a dirigent-jacalin of sugarcane (ShDJ) under varying conditions of water availability

Made available in DSpace on 2019-10-06T17:04:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-02-13 National Institute of Agrobiological Sciences A sugarcane gene encoding a dirigent-jacalin, ShDJ, was induced under drought stress. To elucidate its biological function, we integrated a ShDJ-overexpression construction into the rice Nipponbare genome via Agrobacterium-mediated transformation. Two transgenic lines with a single copy gene in T 0 were selected and evaluated in both the T 1 and T 4 generations. Transgenic lines had drastically improved survival rate under water deficit conditions, at rates close to 100%, while WT did not survive. Besides, transgenic lines had improved biomass production and higher tillering under water deficit conditions compared with WT plants. Reduced pectin and hemicellulose contents were observed in transgenic lines compared with wild-type plants under both well-watered and water deficit conditions, whereas cellulose content was unchanged in line #17 and reduced in line #29 under conditions of low water availability. Changes in lignin content under water deficit were only observed in line #17. However, improvements in saccharification were found in both transgenic lines along with changes in the expression of OsNTS1/2 and OsMYB58/63 secondary cell wall biosynthesis genes. ShDJ-overexpression up-regulated the expression of the OsbZIP23, OsGRAS23, OsP5CS, and OsLea3 genes in rice stems under well-watered conditions. Taken together, our data suggest that ShDJ has the potential for improving drought tolerance, plant biomass accumulation, and saccharification efficiency. Instituto Agronômico (IAC) Centro de Cana PPG-Genética Faculdade de Medicina de Ribeirão Preto Universidade de São Paulo Department of Plant Biology Institute of Biology University of Campinas Instituto de Ciência e Tecnologia Universidade Federal de São Paulo Instituto Agronômico (IAC) Centro de Ecofisiologia e Biofísica Departamento de Biologia Universidade Federal de Lavras Departamento de Biologia Faculdade de Filosofia Ciências e Letras de Ribeirão Preto Universidade de São Paulo Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP) Centro de Energia Nuclear na Agricultura (CENA) University of São Paulo Texas A&M Agrilife Research & Extension Center Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP)