内蒙古阿拉善荒漠灌木适应多样性

本文通过对内蒙古阿拉善荒漠灌木叶的形态类型、果实类型、水分生态型进行统计,并且对沙冬青(Am-mopiptanthus mongolicus)、梭梭(Haloxylon ammodendron)、红沙(Reaumuria soonorica)、阿拉善沙拐枣(Calligonum alas-chanicum)、膜果麻黄(Ephedra przewalsetina)等灌木种子萌发时的水分利用效率进行测定。结果表明:阿拉善荒漠灌木叶的形态类型以正常叶为主,占72.29%,变态叶次之,占27.74%(其中膜质叶占7.43%,肉质叶占10.81%,针刺叶占9.5%)。在11种果实类型中,以蒴果、瘦果居多,分别占17.6%和19.6%。其次为胞果、蓇葖果、浆果,分别占10.1%、9.5%、9.5%。在水分生态型中,以旱生灌木为主,占37.2%;其次为中生和强旱生灌木,分别占2.3%和16.9%。灌木种子萌发时的水分利用效率不同。沙冬青对水的响应慢,敏感程度低。梭梭对水的响应快,敏感程度高。红沙、阿拉善沙拐枣、膜果麻黄对水的敏感程度介于沙冬青和梭梭之间。由此可见,阿拉善荒漠灌木对环境的适应主要表现为:叶为膜质叶、肉质叶、针刺叶;果实以干果为主;水分生态型以旱生为主,灌木种子的水分利用效率方式多样性。

Methods of Testing Seed and Seedling Physiological Traits for the Improvement of Rapeseed Yield Stability

The presented work is based on laboratory testing of seed germination speed, emergence and seedling growth under different stress conditions simulated by subnormal water revel, extreme high and low temperatures. It allows one to eliminate the plant materials （initial breeding materials and cultivars） which do not tolerate extreme temperatures and temperature changes during germination, have low water use efficiency and is intolerant to abiotic stressors all right at the seed level. It was confirmed that these genotypes also have poor t^eld emergence and initial root growth implications for further vegetation periods, mainly for over wintering and spring regeneration which has significant influence on the yield. The method also represents the tool for screening genetic resources with the resistance to the abiotic stressors and this technology process is also acceptable for other crops. The results confirm the importance of the seed and root characteristics for crop production. The deteriorating quality of soil in recent years, increasing variability of weather and long periods of drought directly support the need to intensify activities in this research. Obtained results also show the influence of seed quality characteristics on roots and above ground parts of the plant. A relationship exists also vice versa.