Transgenic improvement of oat for salinity tolerance and rice for alcohol fuel production and reduced air pollution

Environmental stresses such as drought, salinity and air pollution represent some of the most limiting factors for agricultural productivity worldwide. A major cause of oat crop yield loss is osmotic stress due to drought and/or salinity. This study investigated the third generation of transgenic oat (Avena sativa L.) expressing barley HVA1 stress tolerance, beta-glucuronidase (uidA; gus ) and bar herbicide resistance genes. Transgenic plants showed normal 9:7 third generation inheritance for glufosinate ammonium herbicide resistance. Molecular and histochemical studies confirmed the presence and stable expression of all three genes. Compared with the non-transgenic control, transgenic R3 plants exhibited greater growth and showed a significant (P < 0.05) increase in tolerance to salt stress conditions (200 m M NaCl) for traits including number of days to heading, plant height, flag leaf area, root length, panicle length, number of spikelets/panicle, number of tillers/plant, number of kernels/panicle, 1000-kernel weight, and kernel yield/plant.; Rice is the major food crop of the world with minimal use for its straw. A successful strategy for producing biologically active hydrolysis enzymes (molecular farming) in rice for alcohol fuel production provides an environmentally superior technology that substitutes the wasteful and polluting practice of rice straw burning. The catalytic domain of Acidothermus cellulolyticus thermostable endoglucanase gene (encoding for endo-1,4-beta-glucanase enzyme or E1) was constitutively expressed in rice using the Agrobacterium -mediated transformation system in an apoplast-targeting manner. Molecular analyses of R1 plants confirmed presence and expression of the transgene. The amount of E1 enzyme accounted for up to 4.9% of the plant total soluble proteins, and its accumulation had no apparent deleterious effects on plant growth and development. Approximately 22 and 30% of the cellulose in the Ammonia Fiber Explosion (AFEX)-pretreated rice and maize biomass was converted into glucose using rice E1 heterologous enzyme respectively. The results of these two studies provide effective transgennc-based means that can contribute to solving two of the most complex problems for which traditional plant breeding technologies provide only limited answers.