RESUMO
Ascorbic acid (AsA) and selenium nanoparticles (SeNPs) were versatile plant growth regulators, playing multiple roles in promoting plant growth under heavy metal stresses. This study aimed to evaluate the beneficial role of individual and combined effects of AsA and SeNPs on morpho-physio-biochemical traits of rice with or without chromium (Cr) amendment. The results indicated that Cr negatively affected plant biomass, gas exchange parameters, total soluble sugar, proline, relative water contents, and antioxidant-related gene expression via increasing reactive oxygen species (MDA, H2O2, O2â¢-) formation, resulting in plant growth reduction. The application of AsA and SeNPs, individually or in combination, decreased the uptake and translocation of Cr in rice seedlings, increased seedlings with tolerance to Cr toxicity, and significantly improved the rice seedling growth. Most notably, AsA + SeNP treatment strengthened the antioxidative defense system through ROS quenching and Cr detoxification. The results collectively suggested that the application of AsA and SeNPs alone or in combination had the potential to alleviate Cr toxicity in rice and possibly other crop species.
Assuntos
Oryza , Selênio , Antioxidantes/metabolismo , Ácido Ascórbico/farmacologia , Ácido Ascórbico/metabolismo , Plântula , Selênio/farmacologia , Selênio/metabolismo , Cromo/metabolismo , Oryza/metabolismo , Peróxido de Hidrogênio/metabolismo , Estresse Oxidativo , Mecanismos de DefesaRESUMO
Plant lipids, mainly stored in seeds and other plant parts, are not only a crucial resource for food and fodder but are also a promising alternative to fossil oils as a chemical industry feedstock. Oil crop cultivation and processing are always important parts of agriculture worldwide. Vegetable oils containing polyunsaturated fatty acids, very long chain fatty acids, conjugated fatty acids, hydroxy fatty acids and wax esters, have outstanding nutritional, lubricating, surfactant, and artificial-fibre-synthesis properties, amongst others. Enhancing the production of such specific lipid components is of economic interest. There has been a considerable amount of information reported about plant lipid biosynthesis, including identification of the pathway map of carbon flux, key enzymes (and the coding genes), and substrate affinities. Plant lipid biosynthesis engineering to produce special oil compounds has become feasible, although until now, only limited progress has been made in the laboratory. It is relatively easy to achieve the experimental objectives, for example, accumulating novel lipid compounds in given plant tissues facilitated by genetic modification. Applying such technologies to agricultural production is difficult, and the challenge is to make engineered crops economically attractive, which is impeded by only moderate success. To achieve this goal, more complicated and systematic strategies should be developed and discussed based on the relevant results currently available.