共查询到20条相似文献，搜索用时 640 毫秒
1.
塔里木盆地5种藜科植物种子休眠破除方法的研究 总被引：1，自引：0，他引：1
藜科植物是塔里木盆地野生植物中的主要类群,多生长在干旱、盐碱等极端生境中,蕴含丰富的抗逆基因,极具开发利用价值,但因其生存环境恶劣、复杂,种子多具有休眠特性。本试验以具有休眠特性的5种藜科植物种子为材料,研究其休眠破除的方法,旨在为其合理开发利用提供技术参考。结果表明:碱蓬种子打破休眠的最佳方法:150目砂纸打磨1.5min+1 500mg/L的赤霉素(GA_3)溶液浸泡24h;硬枝碱蓬、盘果碱蓬、盐角草种子打破休眠的最佳方法:150目砂纸打磨1.5min+900~1 500mg/L的GA_3溶液浸泡24h;刺藜种子打破休眠的最佳方法:150目砂纸打磨1.5min+1 200~1 500mg/L的GA_3溶液浸泡24h。采用上述方法打破休眠,碱蓬、硬枝碱蓬、盘果碱蓬、刺藜和盐角草种子的最终萌发率分别达到73.33%、92.00%、89.33%、92.00%和90.66%。 相似文献
2.
3.
北京地区乡土地被植物资源丰富,具有较高的开发利用价值.本研究对地黄、米口袋、红花锦鸡儿、白屈菜、蛇莓等乡土地被植物进行种子萌发试验,结果表明:光照促进地黄种子萌发,12h光照条件下,种子萌发率在6d后超过60％.米口袋种子萌发的关键是种皮处理,开水浸泡1晚后,在30℃/20℃条件下,萌发率在8d后超过60％.红花锦鸡儿种子较易萌发,无论光照与黑暗,25℃/15℃还是20℃/10℃条件下,萌发率在3～4d后即超过60％.白屈菜种子萌发较慢,低温有利于萌发,在20℃/10℃条件下,无论光照与黑暗,萌发率在14～17d后超过60％.蛇莓的种子在20℃/10℃和25℃/15℃条件下,萌发率在1周后超过60％,优于30℃/20℃. 相似文献
4.
5.
6.
以崖柏种子为试验材料,研究不同温度条件、光照和持续黑暗、不同浸种时间等对种子萌发的影响,探讨适宜崖柏种子萌发的环境条件。结果表明:适宜崖柏种子萌发的温度为25℃,种子发芽率为88%,20℃和30℃条件下的种子发芽率分别为77%和33%。种子萌发进程在20℃和30℃条件下比在25℃条件下开始的时间晚,萌发持续的时间长。高温会显著提高种子霉变率,30℃条件下的种子霉变率高达40%;光照不是崖柏种子萌发的必要条件。在连续黑暗条件下种子仍可萌发,且种子发芽率、发芽指数、发芽势、霉变率等无明显差别。但在光照下种子持续发芽的时间短,种子霉变率低;浸种72 h、96 h和120 h对崖柏的种子萌发没有显著影响,但浸种120 h的种子发芽率低,霉变率高。浸种72 h即可以满足崖柏种子萌发对水分的基本需求。 相似文献
7.
为探索盐爪爪对荒漠干旱盐碱环境的适应性,研究了不同温度、不同盐分浓度及光照(光暗交替和全黑暗)处理对盐爪爪种子萌发的影响。结果表明,低温或高温能显著抑制盐爪爪种子萌发,种子萌发的适宜温度为30℃/15℃;在同一温度和光照条件下,盐爪爪种子的萌发率与萌发指数随着盐胁迫浓度增加呈现下降的趋势;温度和盐分对盐爪爪种子萌发存在交互作用,低温或高温均显著降低了盐爪爪种子萌发的耐盐性;在同一温度下,光暗交替与全黑暗条件下,种子萌发率有显著差异。在适宜温度下(30℃/15℃),光暗交替与全黑暗条件下种子耐盐临界值分别为393.6 mmol/L和259.0 mmol/L,极限值分别为664.7 mmol/L和403.3 mmol/L,光照能显著提高盐爪爪种子萌发时期的耐盐性。因此,温度和盐分可作为盐爪爪种子萌发时期主要限制生态因子,同时光照也可作为重要的调控生态因子。 相似文献
8.
9.
以红果小檗种子为对象,研究了不同光照、温度、盐胁迫和PEG模拟干旱胁迫条件下,红果小檗种子的萌发特性.结果表明:1)全光照、全黑暗及12h光照/12h黑暗3种不同的光照条件下,红果小檗种子的萌发规律无显著差异,说明红果小檗种子在萌发期对光没有特殊要求,属于中光性种子;2)不同温度条件下,其萌发率、发芽指数和发芽势均呈现出随温度升高而先上升后下降的趋势,且以25℃时最高,说明25℃是红果小檗种子萌发的最佳温度,且在萌发期较耐受低温,但不耐高温;3)在不同浓度的盐胁迫下,其萌发率、发芽指数和发芽势均呈现出随盐浓度升高而逐渐下降的趋势,但低盐胁迫下与对照并无显著差异,说明红果小檗种子在萌发期对低盐有较强的耐受性,0.2 mol/L为红果小檗种子的半致死盐浓度;4)在不同干旱胁迫条件下,其萌发率、发芽指数和发芽势均呈现出随着干旱程度的增加而逐渐下降的趋势,PEG浓度达到10％时,仍有60％以上的萌发率,说明红果小檗种子在发芽期对干旱胁迫具有较强的耐受性,是一种较为耐旱的植物. 相似文献
10.
11.
Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts 总被引：7，自引：0，他引：7
Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed. 相似文献
12.
C. J. Spurr D. A. Fulton P. H. Brown R. J. Clark 《Journal of Agronomy and Crop Science》2002,188(4):275-280
Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality. 相似文献
13.
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
14.
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
15.
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
16.
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
17.
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
18.
[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
19.
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
20.
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