|其他题名||Studies on the Limiting Factors to the Introduction and Cultivation of Several Pedicularis Species from Yunnan Province
2. 首次对马先蒿属植物的种子形态及萌发特性进行了较为系统的研究和分析。结果表明，马先蒿种子的外种皮结构特征可作为新的种间分类依据；种子萌发特性存在较大种间差异，但所有种子的萌发均不依赖寄主植物。多数种类种子萌发对光照要求不严格，但湿生马先蒿种子萌发则表现出较强的需光性。砂纸打磨种皮是一种有效的人工促萌手段，而100和500 mg L-1浓度的GA3促萌效果不明显；多数马先蒿种子具休眠特性。休眠类型为非深度生理性休眠。多数种可经自然后熟打破休眠，而有些则需经低温层积处理才能达到较高萌发率。延长低温层积或自然后熟时间可以有效提高种子萌发速率。18~25 ℃是多数马先蒿较为理想的种子萌发温度。
|其他摘要||Plants belonging to the genus Pedicularis L. have high ornamental values as well as significant biological and pharmacological research values. Unfortunately, cultivation of the genus has long been unsuccessful, which hinders their exploitation to a large extent. Experiments showed that the single-factor (i.e. host plant) cultivation model would not work successfully for the genus. In this thesis, multifactor analysis of specific species is suggested and the important roles of mycorrhizal fungi in the cultivation process of Pedicularis species are pointed out for the first time.
To gain a better understanding of the growth characteristics of Pedicularis from Yunnan Province and the limiting factors to their cultivation, a series of experiments on the survey of their parasitic habit and mycorrhizal status, the micro-observation of seed morphology, the test of seed germination and dormancy, and the multiple-factor cultivation experiments were carried out, with several species distributed in Shangrila County as main study materials. The main results are as follows:
1. Parasitic habit of some Pedicularis from Yunnan Province was examined and experimental evidence of hemiparasitism for Chinese species was obtained for the first time. Also, in this thesis, Pedicularis was systematically and quantitatively surveyed for the first time from a mycorrhizal perspective. The results showed that most examined species could be parasitic and mycorrhizal simultaneously. Three types of potentially beneficial fungi associated with roots of these species were observed, namely arbuscular mycorrhizal fungi (AMF), ectomycorrhizal fungi (EMF) and dark septate endophytic fungi (DSE), with AMF as the dominating mycorrhizal fungi. AMF showed high colonization level in most studied species, suggesting a significant ecological role of these fungi and their potential to be applied to successful cultivation of these intractable plants. Our survey results also suggested that mycorrhization might serve as another nutrient strategy for some Pedicularis species.
2. Seed morphology and germination characteristics of Pedicularis species were studied systematically for the first time. Testa ornamentation and structure of the genus Pedicularis were found to have taxonomic values. There were some significant differences in germination characteristics among the tested Pedicularis species. But all tested species seemed to be independent of host plants for germination. For most species, no strict light requirement was detected. But wet habitat species generally had positive photoblastic responses. For many species, scarification was effective to promote seed germination, but neither 100 nor 500 mg L-1 GA3 had consistent promoting effect. The majority of fresh mature Pedicularis seeds were dormant to some extent. The dormancy showed by the tested Pedicularis species was nominated non-deep physiological dormancy. For most species, seed dormancy could be overcome by after-ripening after stored at room temperature for a period of time. For other species, however, cold stratification was necessary to gain a better germination performance. Our results also showed that seed germination performance could be promoted by elongating the time of cold stratification or after-ripening at room temperature. 18-25℃ was an ideal seed germination temperature range for most tested species.
3. Multifactor cultivation experiments were conducted for several Pedicularis species for the first time. The results showed that soil nutrient level had significant effect on growth of Pedicularis and high nutrient level favored the development of plants at both early growth stage and late growth stage. Complicated variation was detected both interspecifically and growth-stage-dependently concerning the effects of host plants and AMF on plant growth and development of Pedicularis. In addition, some plant diseases and pests affected seedling establishment and growth of Pedicularis in Kunming.|
李爱荣. 几种滇产马先蒿引种栽培限制因子的研究[D]. 昆明植物研究所. 中国科学院昆明植物研究所,2007.