Root apoplastic barrier mechanism: an adaptive strategy to protect against salt stress.

From soil to plant, the water and ions, enter the root system through the symplast and apoplast pathways. The latter gains significance under salt stress and becomes a major port of entry of the dissolved salts particularly the sodium ions into the root vasculature. The casparian strip (CS), a lignified barrier circumambulating the root endodermal cells' radial and transverse walls regulates the movement of water and solutes in and out of the stele.

Strategies for Efficient RNAi-Based Gene Silencing of Viral Genes for Disease Resistance in Plants.

RNA interference (RNAi) is an evolutionarily conserved gene silencing mechanism in eukaryotes including fungi, plants, and animals. In plants, gene silencing regulates gene expression, provides genome stability, and protect against invading viruses. During plant virus interaction, viral genome derived siRNAs (vsiRNA) are produced to mediate gene silencing of viral genes to prevent virus multiplication.

Plant regeneration, developmental pattern and genetic fidelity of somatic embryogenesis derived spp.

Multiplication of banana cvs. Grand Naine ( AAA, Cavendish-sub group) and Rasthali ( AAB, Silk-sub group) were attempted through somatic embryogenesis. The influence of position of male flower buds, amino acid supplements in the induction of somatic embryogenesis and field performance of embryogenic cell suspension (ECS) derived banana plants were studied.

Over-expression of a NAC 67 transcription factor from finger millet (Eleusine coracana L.) confers tolerance against salinity and drought stress in rice.

Background: NAC proteins (NAM (No apical meristem), ATAF (Arabidopsis transcription activation factor) and CUC (cup-shaped cotyledon)) are plant-specific transcription factors reported to be involved in regulating growth, development and stress responses. Salinity responsive transcriptome profiling in a set of contrasting finger millet genotypes through RNA-sequencing resulted in the identification of a NAC homolog (EcNAC 67) exhibiting differential salinity responsive expression pattern.

Methods: Full length cDNA of EcNAC67 was isolated, characterized and validated for its role in abiotic stress tolerance through agrobacterium mediated genetic transformation in a rice cultivar ASD16.

Transgenic rice grains expressing a heterologous ρ-hydroxyphenylpyruvate dioxygenase shift tocopherol synthesis from the γ to the α isoform without increasing absolute tocopherol levels.

We generated transgenic rice plants overexpressing Arabidopsis thaliana ρ-hydroxyphenylpyruvate dioxygenase (HPPD), which catalyzes the first committed step in vitamin E biosynthesis. Transgenic grains accumulated marginally higher levels of total tocochromanols than controls, reflecting a small increase in absolute tocotrienol synthesis (but no change in the relative abundance of the α and γ isoforms). In contrast, there was no change in the absolute tocopherol level, but a significant shift from the γ to the α isoform.

Constitutive expression of a barley Fe phytosiderophore transporter increases alkaline soil tolerance and results in iron partitioning between vegetative and storage tissues under stress.

Cereals have evolved chelation systems to mobilize insoluble iron in the soil, but in rice this process is rather inefficient, making the crop highly susceptible to alkaline soils. We therefore engineered rice to express the barley iron-phytosiderophore transporter (HvYS1), which enables barley plants to take up iron from alkaline soils. A representative transgenic rice line was grown in standard (pH 5.

Critical evaluation of strategies for mineral fortification of staple food crops.

Staple food crops, in particular cereal grains, are poor sources of key mineral nutrients. As a result, the world's poorest people, generally those subsisting on a monotonous cereal diet, are also those most vulnerable to mineral deficiency diseases. Various strategies have been proposed to deal with micronutrient deficiencies including the provision of mineral supplements, the fortification of processed food, the biofortification of crop plants at source with mineral-rich fertilizers and the implementation of breeding programs and genetic engineering approaches to generate mineral-rich varieties of staple crops.

Beta-glucuronidase of family-2 glycosyl hydrolase: a missing member in plants.

Glycosyl hydrolases hydrolyze the glycosidic bond in carbohydrates or between a carbohydrate and a non-carbohydrate moiety. beta-glucuronidase (GUS) is classified under two glycosyl hydrolase families (2 and 79) and the family-2 beta-glucuronidase is reported in a wide range of organisms, but not in plants. The family-79 endo-beta-glucuronidase (heparanase) is reported in microorganisms, vertebrates and plants.

Deletion of the C-terminal 138 amino acids of the wheat FKBP73 abrogates calmodulin binding, dimerization and male fertility in transgenic rice.

Wheat FKBP73 (wFKBP73) belongs to the FK506-binding protein (FKBP) family which, in common with the cyclophilin and parvulin families, possesses peptidyl prolyl cis-trans isomerase (PPIase) activity. Wheat FKBP73 has been shown to contain three FKBP12-like domains, a tetratricopeptide repeat (TPR) via which it binds heat shock protein 90 and a calmodulin-binding domain (CaMbd). In this study we investigated: (1) the contribution of the N-terminal and C-terminal moieties of wFKBP73 to its biological activity by over-expression of the prolyl isomerase domains in transgenic rice, and (2) the biochemical characteristics of the C-terminal moiety.