Adaptation Of Seed (Fruit) Morphological Structures And Germination Characteristics Of Main Desert Plants In Alxa

Study and observation on morphological structure of 53 desert plants and germination character, water character, hot and dry treatment, seed-coat structure of part plants. The results indicated that:(1)the morphological structure of seeds (fruits) of deserts plants are abundant and diversity. The main morphology are kidney-shape, egg shape, oblong, oval, crescentiform, spherical shape and so on,which all like roundness. Main color are brown, gray, which are delicate colors(77.4%), emblazonry on surface are stripe(30.2%), hair on surface(13.2%), cave(9.4%), brain mark(7.6%). part of furits have appurtenance,which are propitious to spread by wind.(2) the rates and periods of germination of 6 plants were different, except Thermopsis lanceolata,the other's germination rate were high, above 35%. The periods of germination were short, germination of 6 plant seeds spent about 7-8 days. And in the process of germination, Thermopsis lanceolata, Nitraria roborowskii and Nitraria tangutorum are lower sensitive to water, Peganum harmalal var. multisectum, Haloxylon ammodendron and Peganum harmalal are higher sensitive to water.(3) the desert plant seeds have high heat-resisting quantity. Haloxylon ammodendron can endure 70℃, Peganum harmalal, Peganum harmalal var. multisectum can endure 80℃, and Thermopsis lanceolata can endure 90℃. And high temperature can increase the rate of germination, cut down the time of germination, increase the rate of absorbing. Through hot and dry treatment, the rate of absorbing of Thermopsis lanceolata, Haloxylon ammodendron, Peganum harmalal, Peganum harmalal var. multisectum, Nitraria roborowskii, Nitraria tangutorum were bigger than no treatment, and difference were remarkable.(4) seed-coat structures of 6 desert plant were different. The seed-coat of Thermopsis lanceolata was thickening and thicker, Haloxylon ammodendron was membrane, Peganum harmalal, Peganum harmalal var. multisectum were thicker but liable to drop, Nitraria roborowskii, Nitraria tangutorum had hard inner peel.(5) Of seeds or fruits of desert plants, the characters of morphological and structural diversity, heat-resisting, high germination rate, short germination periods, and high sensitivity to water are long-term adaptive strategy to drought, percipitation confined to warm season (June–September period), high temperature of the earth's surface, remarkable difference in temperatue between day and night in desert area, which fully incarnate adaptive diversity of morphological structure and germination character in seeds or fruits of desert plants to desert habitat.