Study On Salt Tolerance Controlling Gene Of Castor

Castor has a special fatty acid in its seeds-ricinoleic acid. In the aerospace and automotive industries, castor oils are widely used because of its excellent fluidity and viscosity properties. On the cultivation of castor, it shows a highly adaptive capacity under stress. To improve saline and alkaline land capacity which is hard to plant crops on, one of the commonly used tool is the phytoremediation, salt tolerance of specific plants.The saline/alkali soil includes complicated soluted composition. At present, the general ways to modelize salinity stress is adding NaCl, but the saline/alkali soil cannot be simulated by single solute, therefore the high osmotic potential should be considered. PEG-6000 with a high molecular weight has strong water absoption, and can be used to simulate the low permeability status of the soil in a certain extent. In this experiment, it is used as one of the castor screening indicators of salinity tolerance traits. Seed germination experiment using embryo germination method could reduce the loss of seed endosperm caused by long-term storage, caruncle shedding, dehydration and other stresses.The concentration of PEG-6000 has a significant influence on castor seed germination rate and root length. At the same time, the concentration of NaCl could not only influence germination rate of castor embryo, but also the radicle elongation. Some cultivars are sensitive to high salt concentration during germination stage, but showed a contrast tendency at the seedling stage, and may even have a certain degree of salt tolerance. NaCl induced germination rate and root length variety of the germinating period is likely to indicate a similar variety of biomass accumulation in later stage of plant growth. According to the principal component and factor analysis cluster,25 cultivars of castor germplasm according to the salt tolerant trait scoring is divided into seven gradient. Germination group factors were devided into salt factor and osmotic factor; factors of salt stress group were devided into growth factor and response factor.Castor vacuolar H+-PPase has three complete conserved domains, the conservative region CS1 is in the 234-294 region, which is generally considered as the catalytic site of the enzyme. Sequence analysis results shows phylogenic tree of Castor RcVP Protein and several homologies, including Populus trichocarpa and Morus notabilis. Secondary structure prediction of the deduced amino acid sequence of RcVP shows that there are 14 Possible transmembrane helices and the protein is a hydrophobous one.