PhyA/B Expression And The Determination Of Plant Hormones Analysis Under The Control Of Photoperiod And Temperature In Alfalfa

ABSTRACT: Alfalfa(Medicago sativa)has been gradually concerned as an important forage legume, to ensure national security about meat, eggs and milk's the sustained and steady development and improvement.Fall dormancy in alfalfa was related to several traits of production performance including regrowth, yield and plant height in autumn. Fall dormancy of alfalfa exists a Photoperiodic Effect,meanwhile,Phytochrome is the receptor of Photoperiodic Effect, response Light changes. But whether the role of temperature is response the phytochrome has little research ; And the characteristics of fall dormancy are affected by a variety of factors.The plant hormones influence domency is also important to research.The research show that Photoperiodic and temperature effect on the phytochrome and the amountand balance of endogenous hormones in alfalfa leaves.The temperature conditions :Three varieties norseman,dupuils and CUF101 were treated with 6℃,12℃,18℃,24℃and 30℃during a 35 day period.①The endogenous hormone content at different levels in different temperature conditions :The major results were obtained: both low and high temperature treatment reduced the IAA content of alfalfa leaves, Norseman's zeatin was the highest levels, In various temperature treatments, gibberellin content were lower in the ultra-low temperature than other Temperatures, but increased gradually after the peak down to the lowest point under high temperature conditions; GA3/ABA, IAA / ABA and ZR / ABA decreased, plant height growth variation showed an increasing trend. Each treatment temperature, the ratio of three peaks between 18℃to 24℃. the whole non-fall dormancy > fall dormancy.②The two phytochrome genes named A and B, which is related and restrict each other in phytochrome family . the temperature test: In middleday (12h), the study of different temperature 6℃, 12℃, 18℃,24℃and 30℃during a 35 day period. Norseman,dupuils and cuf101 were tested. With the temperature from from low to high PhyA in the leaves tended to increase its expression,especially norseman and dupuils.Cuf101 On the contrary, the temperature decreased reduce the level of phyA gene expression..While phyB gene expression in norseman and cuf101 increased with increasing temperature, except dupuils.Temperature sensitive performance of phytochrome in the fall dormancy(norseman).Moreover,norseman relative to dupuils and cuf101 decreased significantly(except 30℃). norseman and dupuils phyB gene expression under low temperature higher than high temperature。The photoperiod conditions :Experiment with three different types of alfalfa norseman dupuils and cuf101 were treated light gradient 7h/d,10 h/d, 13 h/d and 16 h/d, the temperature control from 15℃to 25℃, 35 day period.①The endogenous hormone content at different levels in the photoperiod conditions:Enzyme-linked immunosorbent assays( ELISA) were developed for Dynamic Changes of Some Endogenous Hormone Content in leaves under light duration Stress.The results show that the ABA in three types of dormancy from SD (short day) to LD (Long day) is downtrend, which norseman was the most predominant.;Thedifference among the 3 groups was statistic ally significant (P<0.01); norseman highest, followed by dupuils and cuf101;from SD (short day) to LD (Long day) IAA, ZR and GA3 in three types of alfalfa were essentially rising, GA3 content in each dormancy was significant for the norseman> cuf101> dupuils ;The conclusion in the same species: 16h> 13h> 10h> 7h. Determination and analysis of Zeatin to show:cuf101>norseman≥dupuilsThe conclusion in the same species: 16h> 10h≥13h> 7h.Determination of IAA obtained that dupuils changed insignificantly, cuf101 higher than others.Experimental analysis shows that with the increasing illumination time, GA3/ABA, IAA / ABA and ZR / ABA were generally increased with day length raised.In the mass as a whole, fall dormancy was sensitive to temperature-dependent, next was unfall dormancy,dupuils at last. Illustrates the fall dormancy is the strongest on the sensitivity of the environmentof light.②The photoperiod conditions test:The two phytochrome genes named A and B,The day length 7h,10h,13h and 16h were studiedof during a 35 day period. Norseman,dupuils and cuf101 were tested,too. during Different Photoperiod phyA content from the fall dormancy to unfall dormancy were downdraught,PhyB content by light, fall dormancy(norseman) was sensitive species, phyB levels plummeted in the change process.Whatever,the non-fall dormancy alfalfa cof101 almost unchanged.