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研究了新疆阿魏离体胚培养中,不同培养基、光照、温度、碳源、pH值及低温层积、赤霉素、6-苄氨基嘌呤处理等因素对胚萌发及生长的影响。结果表明:诱导胚萌发较理想的培养基为MS(pH值为5.5-6.0)+1mg/L GA3+0.1mg/L6-BA+3%蔗糖;光照对胚的萌发势差异不明显(P=0.334),但存在显著的温度差异(P=0.000),其中20、25、30℃较适宜;离体胚的萌发率随种子低温层积时间的延长而有所下降,推测新疆阿魏种子产生休眠效应的部位可能在胚以外的种皮或胚乳。本研究能有效克服新疆阿魏种子抑制物或种皮本身限制,萌发率可达94%。不仅为新疆阿魏人工培育奠定了基础,也为研究种子低温层积打破休眠的机制提供了新的思路。 相似文献
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海桐种子的休眠解除与萌发 总被引:1,自引:0,他引:1
观赏植物海桐(Pittosporum tobira(Thunb.)Ait.)种子的休眠和萌发特性已被进行了较充分的研究.TTC检测出新鲜海桐种子是高活力的(98%),但在5个恒温和1个变温(12 h/d的光周期)下,其萌发率仅为27%,这说明海桐种子处于休眠状态.经不同浓度(100mM和200 mM)的GA3溶液处理后,新鲜海桐种子的萌发率有所提高;在25/15℃与200 mM的处理下,其发芽率最高是41%,但仍不理想.当经过低温(5℃)处理一段时间(15、30、45、60、90d)后,海桐种子的萌发率显著提高,尤其是在25℃和25/15℃处理下,萌发率分别为87%和95%.此外,冷层积30 d和45 d的海桐种子经200 mM的GA3溶液处理后的萌发率分别达69%和94%,效果显著.可见,海桐种子的休眠是浅生理休眠,单一的GA3溶液处理不能有效地打破海桐种子的休眠,但冷层积90d或200mM GA3溶液处理冷层积45d的种子,可有效地解除其休眠;同时,温度对种子的萌发有较大影响,在适宜的萌发温度(25℃或25/15℃)与周期性(12h/d)光照下,种子的萌发率超过90%.由此推断,海桐种子在自然条件下难以萌发的原因与其生理休眠有关. 相似文献
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濒危药用植物桃儿七种子的萌发特性初探 总被引:4,自引:0,他引:4
目的:研究桃儿七种子萌发特性,探讨桃儿七种子休眠类型。方法:采用称重、测量、解剖等方法,研究种子形态结构及吸水特性,TTC法研究种子活力,通过白菜种子萌发实验,研究萌发抑制物的存在与否,清水与GA。处理相比较方法,研究种子萌发特性。结果:桃儿七种子具有完整的胚结构,能正常吸水,种子生活力高.达98.9%.种子各部分存在萌发抑制物,以胚乳中含量最高,GA,处理和低温处理可以有效提高种子萌发率。结论:桃儿七种子存在休眠现象,休眠类型为生理休眠,GA,和低温可以有效打破休眠,GA3最佳浓度为120mg/L,最佳低温层积时间为60d。 相似文献
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为明晰多籽蒜种子的休眠类型和解除休眠的方法,研究了机械处理和4种化学物质对多籽蒜种子萌发的影响.结果表明:砂纸摩擦处理种子萌发率极显著高于对照;4种化学物质在一定浓度范围内表现为低浓度促进、高浓度抑制种子萌发,最佳处理浓度分别为150 mg/L GA3、5 mg/L 6-BA、0.1 mg/L SA、300 mg/L PG;提高种子萌发率的作用由大到小依次为:6-BA>SA>GA3 >PG;多籽蒜种子的休眠是由种皮障碍和因胚尚未完成生理成熟引起的胚生理休眠共同引起的混合休眠,可以通过机械处理和一定浓度的化学物质调控后解除种子休眠,提高种子萌发率. 相似文献
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辽东楤木种子休眠原因及休眠破除研究 总被引:2,自引:0,他引:2
目的:研究辽东楤木种子休眠原因,确定打破休眠方法。方法:测定种子发芽率及种子活力,种子吸水率,解剖观察种皮结构及种胚形态,提取种内萌发抑制物质,确定种子休眠类型;用GA3丙酮溶液浸泡,再进行变温层积处理,以确定破除休眠的方法。结果:辽东楤木种子种胚的形态发育不完全,种子内部存在多种抑制萌发物质,属于综合性休眠。200 mg/L GA3丙酮溶液中浸泡12 h,再进行变温层积处理30 d(高温20~23℃12 h,低温0~4℃12 h),能有效地解除休眠,萌发率达84%。 相似文献
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Diploid, tetraploid, and hexaploid plants occurred in foreign plant introductions of P. sp. affin. P. montanum from Turkey and Iran. Within-progeny variations in polyploid levels indicate that divergent races occurred as interspersed but natural populations. One to six B-chromosomes of varying sizes in addition to the normal chromosome complement were present in some plants. Their behaviours appeared essentially similar to those recorded for other species. Certain of the plants examined exhibited cytological features similar to those observed in known hybrids. These included prophase pycnosis, stickiness, split metaphase I plates, unoriented chromosomes at M-1, and low levels of pollen stainability. These features were absent in microsporocytes of other plants. Low open-pollination seed set characterized all plants examined. This may be due to hybridity or possibly to response to ecological conditions of the new environment.Results of co-operative work of the Crops Research Division, A.R.S., U.S. Department of Agriculture, and the Wisconsin Agricultural Experiment Station, Madison, Wisconsin.Former Graduate Student, Department of Agronomy, Wisconsin Agricultural Experiment Station, and Geneticist, Crops Research Division, Agricultural Research Service, U.S. Department of Agriculture. 相似文献
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A widely-held belief is that stricter environmental regulations stifle economic growth. To determine empirically the effect of environmental conditions and policies on state-level per capita income growth, a Barro-type economic growth model was estimated for the years 1982 to 1991, which correspond to two consecutive troughs in the business cycle. States with better environmental conditions had significantly higher income growth rates during this period. At the same time, stricter environmental policies did not significantly depress income growth. Data used include recently developed, consistent measures of environmental policy and quality for individual states, as well as data from the 1980 U.S. Census and Bureau of Economic Analysis. 相似文献
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Summary An accession of Avena fatua L. subsp. fatua v. glabrata Peterm. subv. pseudo-basifixa Thell. (A. fatua L. CS Sel. No. 1), collected in Czechoslovakia in 1971, was found to be resistant to a wide range of crown rust races. Analyses of crosses of this oat with cvs. Weikuss, Leanda, Mona, Rodney A, Rodney B, Rodney M, Dodge and K 316 indicated that the resistance of A. fatua CS Sel. No. 1 is conditioned by one recessive gene which is in interaction with one partially dominant gene with additive effect. The expression of rust reaction was affected by temperature. The crown rust resistance genes of A. fatua L. CS Sel. No. 1 were non-allelic with stem rust resistance genes Pg-2 (A) and Pg-4(B). 相似文献