Physiological And Molecular Mechanisms Of Delaying Cucumber Leaf Senescence As Accompany Growth With Wheat

Cucumber(Cucumis sativus L.) is one of the largest vegetable planting area and the area, and occupy a very important economic status in Chinese agricultural production. Plants mature, aging is a complex physiological and biochemical process,and aging process in plants is influenced by environmental factors.Cucumber has a longer time in acomfortable environment, cucumber leaf premature aging in adverse environment. Northern areas cultivated during winter cold oligonucleotide photos and open field cultivation in the southern region of high temperatures can cause premature aging and shorten the seedling leaves life.So,leaf senescence is to limit the production of a long season cucumber important factor.Wheat(Triticum aeslivum L.) is a global cereal crops with allelopathic, and to promote themselves or other organisms or inhibition.Through previous studies had shown that a certain degree of associated wheat promoted the growth of cucumber.This research adopts the field experiment, the associated photosynthetic rate index of cucumber leaf physiological and biochemical indexes and the effect of endogenous hormone levels, supplemented by antioxidant enzyme gene expression and root protein mapping and other related indexes were analyzed, and aimed at preliminary proven associated wheat physiological and biochemical and molecular mechanism of cucumber leaf senescence, to identify associated wheat in the process of aging, in order to further develop the cucumber aging research laid the foundation.Study the main results were as follows:1. Rapid early growth of cucumber, late slow plant growth; plant fresh weight associated wheat were higher than monoculture, and significantly higher than monoculture at40days. Cucumber grows well compared with monoculture that associated wheat may lay a foundation for anti-aging.2. Associated wheat compared with cucumber monoculture, to a certain extent,could increase the content of chlorophyll, slows down the protein degradation speed, increase the superoxide dismutase and peroxidase activity and reduced MDA accumulation.3. The associated effect of photosynthetic indexes of wheat processing is opposite bigger, but have less effect on the fluorescence parameters. Associated wheat processing improved the cucumber photosynthesis rate, stomatal conductance and transpiration rate, photosynthetic parameters, such as reducing the intercellular CO2concentration; Associated wheat processing to improve the world’s largest photochemical quantum quantity. In short, the associated wheat improves the ability to assimilate substances cucumber leaves, cucumber leaves to provide the material basis for slowing aging.4. Plant at later growth stage, accompanying the cucumber leaf and root of wheat processing of GAS and IAA content is higher than that of cucumber monoculture, ABA content was lower than cucumber. Associated wheat may slow the cucumber leaf senescence by adjusting the content of endogenous hormones GA3and IAA to some extent.5. Associated the wheat to make cucumber leaf IPT and PLD gene expression quantity increased; PAO and ETR2gene expression decreased; Cu/Zn-SOD and GS1gene expression quantity upfront than cucumber monoculture, below the cucumber was late. By increasing the amount of wheat associated IPT gene expression, and decreased expression of PAO and ETR2gene while suppressing Cu/Zn-SOD and GS1late gene expression levels, thereby delaying senescence in cucumber leaves.6. Associated wheat protein of cucumber roots have an impact, but the differences in protein point are rare. Analysis of four periods of two-dimensional electrophoresis, and ultimately get45differences in protein, its protein point32, increase protein point13; Including protein in60days difference point, most differences between protein has15points; In40days difference protein point at least, there are11differences; The30th day,50days each have12different protein.To sum up, the associated wheat physiological and biochemical and molecular mechanism of cucumber leaf senescence, preliminary considered by raising the photosynthetic rate and antioxidant enzyme activity, endogenous hormone change mitigation, effectively prevent the accumulation of high concentrations of oxygen, to protect the cucumber and cucumber leaf senescence.