3种荒漠盐生植物根系及根毛形态特征的比较研究

在水培条件下，针对梭梭、囊果碱蓬和钠猪毛菜3种荒漠盐生植物，研究它们苗期在不同盐浓度条件下根系和根毛形态的差异。结果表明：一定浓度的盐分可以促进3种盐生植物生长，但较高浓度的盐抑制其生长，特别是对根系生长的抑制作用更大。在同样盐浓度下，钠猪毛菜的生长最快，生物量也最大。在盐分浓度较低时，3种盐生植物的主根长和总根长都有所增加，与对照相比，囊果碱蓬增加的幅度较大，但高浓度的盐会抑制根系总长度的增加，其中囊果碱蓬较梭梭和钠猪毛菜抑制的程度轻。盐分对3种植物的根系平均直径没有显著的影响，但有减小的趋势。在水培条件下，梭梭和囊果碱蓬的根系上、中、下部分布的较均匀，而钠猪毛菜的根系中部比上部和下部有显著的增加，盐分对每种植物的根系的分布没有显著的影响。3种植物的根毛与根系生长环境中的盐浓度没有明显相关性；3种植物之间，根毛的长度和密度有显著差异。从根系和根毛的形态特征可以推断：囊果碱蓬比梭梭和钠猪毛菜具有较强的抗旱性和耐极薄能力；梭梭的耐盐能力较其它2种植物差，囊果碱蓬的耐盐性最强。

The Comparisons of Root System and Root Hair Morphological Characteristics among Three Desert Halophytes

This research focused on three desert halophyte species,i.e., H. ammodendron (C.A.Mey.) Bge.,S. physophora Pall.,and S. nitraria Pall. under solution culture,and the differences of their root morphology and activity in the seedling stage under varying salt concentration conditions were studied. The results show that a certain salt concentration can promote the development of these three halophytes, but rather high salt concentration will restrain their growth,especially inhibit the roots development. Under the same salt concentration condition,S. nitraria Pall. grows fast and accumulates the largest amount of biomass. Under relatively lower salt concentration,the length of axial root and the total length of roots of these three halophyte species are all increased, comparing to the control samples,S. physophora Pall. occupies the top place of roots growth,but high salt concentration will restrain the increase of total root length, among them,the restraining intensity to S. physophora Pall. is lighter than to H. ammodendron (C.A.Mey.) Bge. and S. nitraria Pall. The salinity does not bring distinct influence on the average diameter of roots of these three plant species,but trends to reduce the size. Under the solution culture conditions,the upper, middle and lower parts of the axial root of H. ammodendron (C.A.Mey.) Bge. and S. physophora Pall. are rather equally distributed,but the middle part of S. nitraria Pall. roots is significantly increased than the upper and lower parts, salt concentration does not bring marked impact on the roots spatial distribution of each species. Differences between root hair morphological characteristics at different salt concentration were tested,but no significant differences were found. Average root length and density was found to change significantly among the three species. Our research indicates that S. physophora Pall. has the highest drought-resistant and infertile-resistant among three desert halophytes. The experimental results show that the saline tolerance capacity of H. ammodendron (C.A.Mey.) Bge. is lower than the other two species,and the capacity of S. physophora Pall. is ranked at the top place.