共查询到20条相似文献，搜索用时 62 毫秒
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在实验室条件下,对南蛇藤(Celastrus orbiculatus Thunb)种子的形态特征、千粒重、生活力、吸水速率及萌发特征进行了初步研究。结果表明:南蛇藤种子平均大小为0.413 cm×0.220 cm×0.194 cm(长×宽×厚),千粒重约8.269 g;自然条件下产出有活力种子比例为69%左右;种皮具有较好的透水性,但因其较厚、硬的外种皮束缚了种胚的生长,影响其透气性,从而引起种子休眠;破种皮与3 mmol/L的赤霉素同时处理种子可使种子的发芽率达到29.33%,而完整种子同时用赤霉素处理、完整种子不用赤霉素处理、破种皮但不用赤霉素处理3种条件下,均不萌发。种皮机械障碍和胚的生理后熟均是引起南蛇藤种子休眠的原因。 相似文献
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西南鸢尾种子萌发特性初步研究 总被引：4，自引：0，他引：4
以西南鸢尾种子为研究对象,从种皮透水性、不同光温条件下种子萌发率以及低温湿沙层积和赤霉素处理对打破种子休眠的效应等方面对西南鸢尾种子萌发特性进行了初步研究。结果表明,种皮透水性良好,在浸水2h后吸水量迅速增加,在48h后达到吸水高峰。4种恒温15、20、25、30℃和3种变温20／10、25／15、30／20℃条件下,发现种子萌发最适温度为30／20℃,同时有光条件下的种子萌发率明显高于无光条件,即西南鸢尾种子萌发具有需光性。种子在5℃湿沙层积1～6个月后,萌发率提高18.3％～48.9％。而不同浓度的赤霉素（50～600mg／L）处理24h后均没有提高种子萌发率,以上结果表明西南鸢尾具有非深度生理体眠特性。 相似文献
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伏毛铁棒锤种子休眠与破除休眠方法研究 总被引：1，自引：0，他引：1
为探讨伏毛铁棒锤种子休眠原因及破除种子休眠的方法,利用TTC法测定伏毛铁棒锤种子活性;流水冲洗种子、不同层积方式处理、赤霉素浸种处理,测定其对种子萌发的影响;测定伏毛铁棒锤种子提取物对白菜、伏毛铁棒锤种子的抑制活性。结果表明,伏毛铁棒锤种子生活力可达到90%,14 h种子吸水达到饱和,种皮透水性较好,种仁粗提物浓度为0.8 g/mL时,白菜种子发芽率仅为38.3%,说明种子含有内源性抑制物质。流水冲洗种子可以部分地去除抑制物,提高萌发率;低温层积和变温层积可以有效地打破休眠,尤其低温层积,发芽率达到79.67%;200 μg/mL赤霉素处理24 h对种子萌发效果最好,发芽率高达82%。 相似文献
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苦参种子形态特征及萌发规律研究 总被引：1，自引：0，他引：1
采用称重、测量、解剖等方法,研究苦参种子的形态结构及吸水特性,TTC染色法测定种子生活力,选取来源于岷县和成县的苦参种子,经过沙擦处理和未处理研究其萌发过程和特性。结果表明,苦参种子的硬实率高达90%以上,经测定种子生活力为78%,种子存在吸水困难。未经处理的种子萌发速度缓慢,置23℃恒温条件下的种子吸水膨胀后第5天才有胚根露出种皮,15d完成萌发过程,且萌发率低。经过沙擦处理的种子,其吸水速度加快,种子的发芽率显著高于未处理的种子,说明坚硬的种皮是阻止种子吸水和萌发的主要因素之一。 相似文献
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以锥连栎(Quercus franchetii)种子为实验材料,研究了不同温度(10,15,20,25,30,35,40℃)和去种皮与非去皮处理对种子萌发的影响.结果表明,种皮对锥连栎种子的萌发率(GP)、萌发指数(GI)和萌发速率系数(CRG)的影响极显著(p＜0.01),温度及二者的交互作用对除萌发率外的其他2个萌发参数的影响均极显著(p＜0.01).种皮对锥连栎种子的萌发具有明显的抑制作用,除去种皮后,种子的萌发率及萌发指数极显著增加(p＜0.01),且萌发进程加快.去种皮种子萌发的最适温度为25℃,最高萌发率达100％,升高或降低最适温度都会影响其萌发.有种皮种子萌发率最高仅为10％.锥连栎种皮水浸提液处理下的去种皮锥连栎和小麦种子的萌发率无显著差异(p＞0.05),表明种皮对锥连栎种子的萌发无化学他感作用,但具有明显的机械抑制作用. 相似文献
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北枳椇种子萌发特性研究 总被引：1，自引：0，他引：1
通过研究北枳椇种子的吸水特性、光照、温度、硫酸、赤霉素、低温层积等条件处理对北枳椇种子萌发的影响;测定不同保藏时间北枳椇种子的活力及发芽率和不同覆土厚度对北枳椇种子萌发的作用,探讨了北枳椇种子的萌发特性及其贮藏特性.结果表明:刚采收的北枳犋种子不存在生理休眠,生活力高达86%;北枳椇种皮坚韧,对胚具有机械限制作用,发芽周期超过100d,且发芽不整齐;光照对胚发芽无显著影响;45 d低温砂藏促进其种子萌发;0.5～4 g/L.浓度GA,的处理对其种子萌发促进作用不显著;用浓硫酸处理12 min后,在25℃温度下北枳椇种子30 d发芽势由不处理的21.67%提高到75.4%;北枳椇种子活力在常温下可以保存数年,保藏1年后的种子可能由于老化的原因,萌发时需要改进处理方法以提高发芽率;北枳椇为子叶出土型种子,育苗覆土小于0.5 cm为好. 相似文献
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Jens Jensen 《Euphytica》1979,28(1):47-56
Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans. 相似文献
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G. H. Kroon 《Euphytica》1994,76(1-2):125-125
Summary
K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes. 相似文献
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Hongyan WEI Jian ZHOU Jinguang LU Jingzheng SONG Qiongxi YU Zhihong JIANG 《Medicinal Plant》2019,(6):27-29
[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol... 相似文献
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Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed. 相似文献
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D. A. Bond G. J. Jellis G. G. Rowland J. Le Guen L. D. Robertson S. A. Khalil L. Li-Juan 《Euphytica》1993,73(1-2):151-166
Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses. 相似文献
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Chunli TANG Fengxian ZHAO Hongxia CHEN Jiabao MA Jiangcun WEI Meiyan QIU Zhen XIE 《Medicinal Plant》2019,(6):60-65
[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination... 相似文献
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E. Keep 《Euphytica》1986,35(3):843-855
Summary Cytoplasmic male sterility (cms) is described in the F1 hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf
1) and recessive for the other (Rf
2).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph
3(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf
1(one of two dominant additive genes controlling early season leafing out) indicated that Rf
1and Rf
2were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf
1, and 0.15 for Lf
1-Sph
3were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph
3.It is suggested that competitive disadvantage of lf
1-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph
3. Poor performance of lf
1- (and possibly lf
2-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off). 相似文献
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[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho... 相似文献
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Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed. 相似文献
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Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques. 相似文献