准噶尔荒漠120种植物粘液繁殖体的甄别与比较

用粘沙法对准噶尔荒漠22科81属120种植物进行了粘液繁殖体的甄别和粘沙能力比较试验,结果表明:①共有22种植物具有粘液现象,占总数的18.33%,集中于菊科、十字花科和车前科;②综合浇水2 mm和水浸20 min两种处理结果发现,分泌粘液粘沙后种子重量变化较大的植物有盐生车前、光苞独行菜、庭荠和栉叶蒿等,且对于大多数物种来说,水浸20 min处理时的粘沙量明显高于浇水2 mm处理时的粘沙量;③两种处理结果所得粘沙量大小排序稍有不同,进行平均后得到的顺序是:盐生车前>光苞独行菜>庭荠>栉叶蒿>独行菜>抱茎独行菜>条叶庭荠>条叶车前>小果亚麻荠>小车前>亚麻荠>全缘独行菜>毛果群心菜>播娘蒿>群心菜>四齿芥>油蒿>甘新念珠芥>大蒜芥>多型大蒜芥>棱果芥>山柳菊叶糖芥;④除群心菜、条叶车前、小车前外,其他19种植物的未粘沙种子单粒干重均小于1 mg;粘沙能力与种子单粒干重之间没有显著关系,而单粒干重<0.5 mg的种子其粘沙能力相对较强;⑤粘液繁殖体是某些荒漠植物降低位移、适应流沙或干旱环境的一种有效手段,但在粘沙能力和适应不同粘液溶出条件等方面表现出物种之间的差异性。

Screening and Comparison on Myxospermy of 120 Species Occurring on the Junggar Desert

Myxospermy is an effective mechanism for some plants to adapt the arid desert environment. A screening on myxospermic diaspores of 120species occurring on the Junggar Desert was conducted to: ①examine what species excrete mucilage, and ②compare the sand-holding capacity between different species which excrete mucilage. Of the 120 species examined, 22 species had myxospermic diasporas, accounting for 18.33% of the total study materials, focus on Compositae, Cruciferae and Plantaginaceae. In both treatments, i.e. watering with 2 mm rainfall and soaking for 20 min, big changes of seed weight after sand-holding happened in the species such as Plantago maritime, Lepidium latifolium, Alyssum desertorum and Neopallasia pectinata. Meanwhile, the changes of seed weight were bigger in the latter treatment than the former one. The mean amount of sand held by mucilaginous diasporas in both treatments was ordered as: Plantago maritime>Lepidium latifolium>Alyssum desertorum>Neopallasia pectinata>L. apetalum>L. perfoliatum>A. linifolium>P. lessingii>Camelina microcarp>P. minuta>C. sativa>L. ferganense>Cardaria pubescens>Dsacurainia Sophia>C. draba>Tetracme quadricornis>Artemisia ordosica>Neotorularia korolkovii>Sisymbrium altissimum>S. polymorphum>Syrenia siliculosa>Erysimum hieracifolium. For 22 species with myxospermic diasporas were small, less than 1 mg except C. draba, P. lessingii and P. minut. Mini-weight diasporas with less than 0.5 mg usually had stronger sand-holding capacity. The mean amount of sand held by mucilaginous diasporas under the first treatment was slightly negative to seed mass (rW2_(mm) = -0.043 , P>0.05), compare to relatively positive relationship under the second treatment(rS20_(min) =0.029, P>0.05). In general, there were differences in the mean amount of sands held by mucilaginous seeds and the weight increment of sand-holding seeds between different species.