The Study On Physiological Characteristics Of Different Generations And Drought Resistance Of Microlepia Strigosa

In this paper, the phsiological characters of Microlepia strigosa （Thunb.）Presl. ofdifferent generations were studied. The results showed that from gametophyte to themature sporophyte stage in the development process of Microlepia strigosa. MDAcontent of the old gametophyte higher than the gametophyte. The content of MDA inthe mature sporophyte was significantly higher than other young sporophytes. SOD,POD and CAT activity in the gametophyte higher than the old gametophyte. SOD,POD and CAT activity of the mature sporophyte was significantly higher than otheryoung sporophytes. That plant growth to the late aging caused by the cell membranehurt. With the increase in MDA content caused by the protective enzyme system startup.Ensure normal growth and development of plants to remove harmful substances.In the descend order of the concentration of soluble proteins, listed are the maturesporophyte, young sporophytes six to eight leaf stage, young sporophytes three to fourleaf stage, young sporophytes two leaves, old gametophyte, gametophyte. The contentof soluble sugar in the gametophyte higher than the old. But little overall change in theperiod of sporophyte, it’s arranged from lower to upper which goes like this youngsporophytess three to four leaf stage, young sporophytes six to eight leaf stage, youngsporophytes two leaf stage and the mature sporophyte. The content of soluble sugarreduce the growing period has been consumed.The chlorophyll content of gametophyte is lower than the old gametophyte,sporophyte during the chlorophyll content of arranged from lower to upper which goeslike this: young sporophytess three to four leaf stage, young sporophytes six to eightleaf stage, mature sporophyte. Gametophyte photosynthetic rate and respiration rate andtranspiration rate were significantly higher than the old gametophyte. In the rise order ofthe photosynthetic rate and respiration rate in sporophyte period, listed are youngsporophytes two leaf stage, young sporophytes three to four leaf stage, youngsporophytes six to eight leaf stage, the mature sporophyte period. In the rise order of thetranspiration rate listed are, young sporophytess three to four leaf stage, youngsporophytes six to eight leaf stage, mature sporophyte, young sporophytes two leaf stage. Show that the rise of the chlorophyll content in favor of capture more light, and infavor of plant photosynthesis, photosynthetic rate and transpiration also will increase.The perennial mature sporophyte of Microlepia strigosa as test material. Pottedyoung sporophytess natural drought stress, osmotic adjustment system, respiratory andphotosynthetic aspects of drought stress fern mature sporophyte physiologicalcharacteristics of the coarse scales cover the protective enzyme system. Of the maturesporophyte of coarse scales cover fern to drought stress response and physiologicaladaptation mechanisms. The results showed that: under drought stress in coarse scalescover the mature fern spores constitution relative permeability of membrane to the riseof MDA was increased and then decreased again an upward trend. H2O2and O2.-contentincreased first and then decreased. SOD activity showed a downward trend, the PODactivity is rising, and CAT activity was increased and then decreased trend. Theaccumulation of H₂O₂and O₂.-showed that cell membrane caused by injury underdrought stress. Two enzymes POD and CAT showed a certain response.Under drought stress in Microlepia strigosa mature sporophyte of soluble sugarand proline content showed an upward trend. Soluble protein showed increased toreduce the tendency to increase again. Showed that the increase in soluble sugar andproline content in drought resistance of plants play an important role. Stomatalconductance, net photosynthetic rate, transpiration rate, respiration rate, chlorophyllcontent showed a downward trend, the intercellular CO2concentration showed a trendfirst and then decreased under drought stress. Show that Stomatal factors accounted forthe dominant factor under drought stress.