Growth Comparison Of 26 Plants In Arid Areas And Studies On Physiological And Biochemical Characteristics Of Drought Resistance Of Seedings Of Five Families In Elaeagnus Angustifolia L.

26 kinds of representative xerophilous arbor and shrub from Kubuqi Desert were used as tested material and the drought resistance was estimated by subordinate function method.The drought-resistant species,Elaeagnus angustifolia L.,was taken as the material in the subsequent studies.The mechanism of drought resistance was investigated in the sight of physiology and biochemistry on the family level.The main results of research are as followings:1.Drought resistance of 26 xerophytes species grown in the arid region of Inner Mongolia was identified based on five growth indexes including stem length and leading thread,and estimated the drought-resistance of 26 xerophytes species with subordinate function method.The sequence of drought resistance of 26 xerophytes species was Populus euphratica Oliv＞P.simonii carr.×P.euphratica oliv.＞Buddleia altemifolia Maxim＞Elaeagnus angustifolia L.＞N.sibirica Pall＞Elaeagnus xycarpa Schlecht.＞Salix integra Linn.＞Salix gordejevii Chang et Skv.＞Salix psammophila C.wang et Ch.Y. Yang＞Zygophyllum xanthoxylon(Bunge) Maxim＞Prunus.Davidana(carr.) Franch＞Prunus armniaca L＞Elaeagnus rnoorcroftii Wall.ex Schlecht.＞Shepherdia argentea V.＞Prunus tomentosa Thunb＞Nitraria tangutorum Bobr.＞Prunus pedunculata(Pall.)Maxim＞Nitraria schberi L.＞Hippophase rhamnoides L.＞Nitraria schoberi L.＞Maclura pomifera(Raf.) Schneid＞Caryopteris mongolica Bge.＞Prunus mongolica Maxim.＞Helianthemum songaricum Schrenk.＞Tetraena mongolica Maxim.＞Prunus humilis Bunge.2.Under the drought stress,the growth of five Elaeagnus angustifolia L.families is inhibited,the stem length,leading thread,SLW and total biomass show a decline with the increase of water stress, while the root shoot ratio rises.The water potential and water relative content in leaves of the five families reduced with the increase of drought stress,while the water saturated deficit increase.And,the content of proline which roles as the osmotic adjustment substance increase.3.Under the drought stress,the active oxygen scavenging system of the five families is inhibited; the MDA,relative electrical conductivity rate and Car increase,and the activity of POD and SOD is enhanced.4.Under water stress,photosynthesis ability of five Elaeagnus angustifolia L.families has been suppressed due to stomatal restriction.The results show that,fluorescent indexes:Fv/Fm,Yield and qP decrease,while qN increase;which represent that PSⅡReaction Center reduces its degree of openness and enhances its heat dissipation capacity.5.Determine the drought resistance of five Elaeagnus angustifolia L.families by principal components analysis,the results showed that 04 has the strongest drought-tolerance under the condition of T1;02 has the strongest drought-tolerance under the condition of T2 and T3.In the three water-stress gradients,01 always behaves the worst of all.From the results,we know that the 02 family of Elaeagnus angustifolia L.has the strongest drought-resistance among five families,and it could be the best choice for planting in the arid region.