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61.
茶花无性繁殖实践经验小结 总被引:1,自引:0,他引:1
通过对茶花进行插穗、插叶芽、嫁接幼芽、大树嫁接换冠四种无性繁殖试验,扦插繁殖成苗率分别为80.8%、48.1%,嫁接繁殖成活率分别为85.3%、90%,表明叶芽繁殖不易控制,成苗率较低;大树嫁接换冠繁殖的成活率较高;嫁接繁殖比扦插更具优势。 相似文献
62.
雷竹鞭侧芽发育过程中核酸含量,过氧化物酶和淀粉酶同工酶的变化 总被引:4,自引:0,他引:4
雷竹鞭侧芽从潜伏芽、饱满芽发育为萌发芽、强萌发芽,核酸含量有规律地显著上升,潜伏芽与饱满芽过氧化物酶的活性和变化有相同的规律,总体活性较强,笋期后活性急剧上升,而和萌发芽、强萌发芽有显著差异;不同类型侧芽,过氧化物酶和淀粉酶同工酶明显不同,存在遗传信息顺序表达的规律,这种表达是内外环境相互作用的结果;从核酸含量、过氧化物酶的活性及其同工酶和淀粉同工酶变化看,从潜伏芽、饱满芽到(强)萌发芽,从萌发芽萌发到笋是两个较为独立的变化过程。 相似文献
63.
分离了香石竹(Dianthus caryophyllus)两个促分裂原活化蛋白质激酶(mitogen-ac-tivated
protein kinase,MAPK)基因cDNA 全长,分别命名为DcMAPK1 和DcMAPK2,其中DcMAPK1 与拟南
芥AtMAPK6 高度同源。DcMAPK1 在香石竹花瓣衰老过程表达增加,乙烯处理显著促进其表达,瞬时抑
制DcMAPK1 后切花瓶插寿命显著延长。而DcMAPK2 在花瓣衰老过程中组成型表达,乙烯处理对其表达
无显著影响,瞬时抑制DcMAPK2 对切花瓶插寿命无显著影响。 相似文献
64.
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66.
Alnus trabeculosa Hand.-Mazz. is classed as “near threatened,” and efforts should be made to conserve the species, but effective action would
require understanding of its genetic variation and structure. Therefore, the genetic variation at 12 isozyme loci was examined
in seven populations of the species in Japan. The expected heterozygosity within species (H
es=0.222) and the expected heterozygosity within populations (H
ep=0.199) were found to be slightly higher than in most other woody species. The coefficient of genetic differentiation (G
ST=0.146) was also high. The northernmost population had the lowest values for almost all measures of genetic variation, and
populations in southern Japan tended to show greater within-population variation than those in northern Japan. The level and
distribution of genetic variation in this species might be related to its life history and ecological traits, and distribution
history. 相似文献
67.
Some of the most frequently chosen approaches to forest population genetics as reflected in the present volume are discussed, and some topics possibly deserving more attention are addressed. Among the first are studies of self-fertilization as a characteristic of forest tree mating systems, gene markers as indicators of adaptive or phylogenetic differentiation, and methodological aspects of the measurement of genetic differentiation. The latter mainly concern generalizable methods of analysis and the involvement of gene markers in the determination of mating systems, detection of mechanisms of frequency dependent selection, and the incorporation of genetic profiles (characteristics of frequency distributions of genetic types) into population genetic analysis. 相似文献
68.
Kevin L. O'Hara 《New Forests》1995,9(1):53-60
Reconstruction in twenty single-cohort stands across five climax series on the eastern slope of the Washington Cascade Range found a variety of species combinations and development patterns. Western larch (Larix occidentalis Nutt.) and lodgepole pine (Pinus contorta Dougl. ex Loud) were found to be very competitive species that usually occupied a dominant position in stands in the Abies grandis, Abies lasiocarpa, and Tsuga mertensiana climax series. Interior Douglas-fir (Pseudotsuga menziesii var. glauca (Mirb.) Franco) was found in all five climax series and, although its height growth was less than that of western larch or the lodgepole pine, it was usually found in the upper stratum. These results suggest that site classification based on climax potential should be used cautiously when applied to young stand management decisions regarding seral species. For example, the difference between an Abies grandis, and a Tsuga mertensiana climax series is quite large in terms of potential productivity but in either case western larch, if present, will likely dominate these stands. 相似文献
69.
INTRODUCTIONLarlxolgcnsisisoneofthemainlyusedspeciesintl1ecastforestareaofnortheastChina.Itgrowsthstandhashighcomprehen-six'cusedvalue.So,itisdeeplylovedbypeo-ple,tl1cafforestionarcaisenlargedgraduallyyearbyycar.needsofitsseedsbecomegrcaterandgrcater.Forsccd-bearingcyclcanddal11-agcofIatclYostinproducingseedpcriod,tl1coutputisvel3'low,andseedsforaflbrcstingarcoIlcnil1sufficient.So'itisurgenttostlldycffcctoflot"tcmperatureonfemaleandmalel1otversofIarixolgcnsissotl1atmethodsofillcrcasingf… 相似文献
70.