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51.
matK was conducted using 41 Trillium taxa and two out-group taxa (Veratrum maackii and Helonias bullata). A total of 1608 base pairs were analyzed and compared., and then there were 61 variable (36 informative) sites among Trillium species. Fifteen insertion/deletion events (indels) of six or fifteen base pairs were also detected. Phylogenetic analyses of the sequence data revealed that the subgenus Phyllantherum (sessile-flowered species) forms a distinct monophyletic group, whereas the subgenus Trillium (pedicellate-flowered species) does not form a monophyletic group, and is composed of three distinct groups and three basally located species in the tree: (1) the Erectum group, (2) the Grandiflorum group, and (3) the Pusillum group and (4) the three species, including T. govanianum, T. undulatum, and T. rivale. T .rivale appears to be the most basally diverged and a very specialized taxon among the ingroup members. Our matK data indicated that the closest relative of the subgenus Phyllantherum is the Grandiflorum group. The results are concordant with the results of the RFLP analysis of cpDNA and also more or less with those of the cladistic analysis of morphological characters. Received 11 September 1998/ Accepted in revised form 25 December 1998  相似文献   
52.
明确不同磷水平条件下接种丛枝菌根真菌(AMF)对桔梗质量与产量的影响.采用盆栽法,设计P0(20 mg/kg)、P1(50 mg/kg)、P2(80 mg/kg)、P3(140 mg/kg)共4个磷水平,同一磷水平分别接种摩西斗管囊霉(Funneliformis mosseae,FM)、根内根孢囊霉(Rhizophag...  相似文献   
53.
Abstract Predominant self-pollination was confirmed in mixed populations of Trillium apetalon (4x = 20, SSUU) and T. smallii (6x = 30, K1K1SSUU). In pollination tests conducted on both species from the Muroran (Mr) population, many good seeds were obtained from bagged flowers as well as open-pollinated intact flowers. In striking contrast, fruits from castrated open-pollinated flowers failed to give any good seeds. In T. smallii in the Usu (Us) population, the same results were obtained for bagged and open-pollinated intact flowers. On the other hand, fruits from castrated open-pollinated flowers yielded only a few good seeds. Although both species were experimentally cross-compatible in both directions, no interspecific hybrids have so far been found in nature. It may be possible that both species are isolated by predominant self-pollinatioin even though their flowering seasons coincide.  相似文献   
54.
空间诱变对露地栽培菊矮化性状的影响   总被引:3,自引:0,他引:3  
洪波  何淼  丁兵  张敩方 《植物研究》2000,20(2):212-214
经卫星搭载处理的露地栽培菊四品种:A,C,E,H与对照比较, SP1代株高变化除H品种外均差异不显著。诱变后的矮化变异主要出现在SP2代和SP3代。在SP2和SP3代,诱变植株还出现了10cm的超矮现象。  相似文献   
55.
Abstract The population struaures, spatial and temporal distributions of individual plants, and survivorship were investigated in four Japanese Trillium species (Liliaceae), T. kamtschaticum, T. tschonoskii, T. apetaion and T. smallii.
The stage class structures of these four species based on leaf area categories all showed similar depletion curves associated with an increase in stnge class. That is, there occurs a conspicuous decrease in early juvenile stages, subsequent leveling-off in the intermediate stages and a slight decrease again in the larger stages. The high mortality in juvenile stages was also confirmed by continuous observations in the permanent plots established on the forest floor for T. kamtschaticum and T. apetalon. Furthermore, the analysis of spatial distribution patterns for T. kamtschaticum and T. apetalon revealed successive distributional changes from under-dispersed (aggregated) to random or overdispersed with the progress of the growth stage.  相似文献   
56.
Previous studies examining the seeds of most Trillium species have reported double dormancy, a type of seed dormancy where two cold periods and one warm period are needed for complete germination. In the present paper, we describe a field study examining the federally endangered Trillium reliquum Freeman (Trilliaceae) in which moderate to high numbers of seeds germinated after one winter following seed production. Sixteen baskets with seeds were placed in four T. reliquum populations (four baskets in each population) in Georgia, USA, in June 2005. In spring 2006, all seed baskets contained seedlings. Germination percentages ranged from 33.3 to 83.3% across sites with a mean of 56.9 ± 3.9%. Trillium reliquum had higher germination percentages compared with other field‐based germination studies with other Trillium species. Our findings will inform future demographic studies of T. reliquum and suggest that double dormancy in seeds may not be as widespread as previously reported within the genus Trillium.  相似文献   
57.
Yokosuka A  Mimaki Y 《Phytochemistry》2008,69(15):2724-2730
Six steroidal glycosides, along with 14 known compounds, were isolated from the underground parts of Trillium erectum L. (Liliaceae). The structures of 1-6 were determined on the basis of extensive spectroscopic analysis, including two-dimensional (2D) NMR data, and a few chemical transformations. The isolated compounds were evaluated for their cytotoxic activity against HL-60 human promyelocytic leukemia cells.  相似文献   
58.
Previously, Narumi et al. (2005) generated chrysanthemum plants transformed with a mutated ethylene receptor gene (mDG-ERS1(etr1-4<), and showed that thein vitro plantlets of the transformants grown aseptically in a small plastic container had a reduced sensitivity to ethylene resulting in reduced leaf yellowing after exposure to exogenous ethylene. In the present study we evaluated ethylene sensitivity of the transformants using soil-grown mature plants. When the shoots detached from soil-grown plants were treated with exogenous ethylene under continuous light, leaf yellowing (senescence) was delayed in the transformants as compared with the non-transformed plants. Furthermore, when the detached shoots were kept in darkness without ethylene treatment, the transformants showed reduced senescence as compared with those of the non-transformed plants. These results demonstrated that the mutated ethylene receptor genemDG-ERS1(etr1-4) could confer reduced sensitivity to ethylene in the leaves of mature chrysanthemum plants. This gene may be useful to generate transgenicCompositae vegetables with leaves green for a longer time and thus having a longer shelf life.  相似文献   
59.
60.
以大花飞燕草‘夏季天空’切花为材料,以清水为对照,采用14种不同保鲜剂对其进行保鲜处理。结果表明,SOD活性总体变化先上升再下降;CAT活性变化与SOD类似;POD活性,6-体呈上升趋势;MDA含量呈波动上升趋势;Pro含量呈先减少后又波动增加;可溶性蛋白质含量先增后减。同时发现各保鲜剂均能不同程度延长大花飞燕草切花的瓶插寿命,提升酶促系统的综合作用,降低MDATZPro含量,减缓蛋白质降解,延缓切花衰老,提高观赏品质,其中以保鲜剂1%蔗糖+200mg·L-1 8-HQS+50mg·L-1 AgNO3+50mg·L-1 Al2(SO4)3保鲜效果最佳。  相似文献   
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