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1.
不同温度对沙棘种子萌发的影响 总被引：11，自引：1，他引：11
本文在水、气、基质等适宜,8h光照条件下,主要研究了恒温分别在20℃、25℃、30℃,变温为20～30℃的不同温度处理条件对沙棘种子萌发和发芽率的影响,并采用胚根生长量和发芽指数对沙棘种子发芽效果进行了评价,提出了沙棘种子发芽的最适温度.在不同温度下,沙棘种子萌发率和胚根生长速度明显不同,认为沙棘种子最适萌发温度为20～30℃的变温.就根生长量来看,沙棘种子表现为喜温.在一定温度条件下范围内,随温度的升高,胚根生长量较大. 相似文献
2.
通过种子萌发试验,研究了温度、光照、赤霉素以及储藏对灰岩皱叶报春种子萌发的影响.结果表明,灰岩皱叶报春种子为光敏种子;最适萌发温度为20℃,变温(15℃12h,25℃12h)可提高种子对高温的耐受能力,加快了种子的萌发速度;赤霉素处理提高了种子萌发速率和萌发势,缩短种子的萌发持续时间,能打破黑暗对种子萌发的抑制;4℃储藏有利于保持种子的品质. 相似文献
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高温胁迫对芹菜种子萌发和幼苗生长以及叶绿素荧光参数的影响 总被引：1，自引：0，他引：1
以耐热性不同的4个芹菜品种(韩育黄芹,3号,黄心芹,申香芹)为材料,在15,25,30,35℃不同温度条件下(以20℃为对照),通过对不同耐热品种的比较分析,研究高温胁迫对芹菜种子萌发以及幼苗生长的影响.结果表明:与对照相比,在30℃高温条件下芹菜种子发芽率、发芽指数、发芽势和活力指数显著降低,且品种耐热性越强,受抑制程度越低.高温对幼苗的根系有显著抑制作用,但对株高影响不明显.同时,在35℃高温处理下,不同耐热性芹菜品种植株相对生长量表现差异显著,叶片的叶绿素含量和叶绿素荧光参数Fv/Fm,YⅡ和qP都有不同程度下降,且表现为芹菜品种耐热性越差,下降趋势越明显,NPQ则呈现相反的趋势.进一步模拟38℃高温,调查热害指数发现72 h高温处理后各品种芹菜差异最显著,且与田间观察结果一致. 相似文献
5.
以4个唐山秋瓜品系为试验材料,在种子萌发期进行不同温度的高温处理,研究高温对其种子萌发的影响,并通过对不同温度下各品系的发芽率、发芽势、发芽指数、活力指数进行分析,比较不同品系间种子萌发的耐热差异,从而筛选出唐山秋瓜种子发芽期耐热性鉴定的温度指标.试验结果表明:26~32℃是唐山秋瓜种子萌发的适宜温度.当温度达到35℃以上,4个品系的种子发芽率、发芽势、发芽指数、活力指数均呈递减趋势,38℃处理对4个品系发芽指标的抑制作用显著高于35℃处理,且同一处理温度下不同品系对高温胁迫的反应不同.通过对各项指标进行综合比较分析,认为38℃是唐山秋瓜种子萌发期耐热性鉴定的适宜温度,适宜鉴定指标为种子活力指数.不同胁迫温度下唐山秋瓜各品系间的发芽能力存在明显差异,4个品系中LB在高温下发芽能力最强,其次为XL,A5和S5发芽期耐热性较差. 相似文献
6.
《种子》2018,(10)
为探明勐腊毛麝香种子的萌发特性,为大规模生产种植提供理论依据,设置了7个恒温处理(5,15,20,25,30,35,40℃)和3个变温处理(20℃/10℃、25℃/10℃、30℃/20℃),对来自3个不同居群的勐腊毛麝香种子的萌发特性进行了深入研究。结果显示,勐腊毛麝香种子的最低萌发温度为20℃,最高萌发温度为40℃;最适萌发温度为30℃,在该温度下,种子的发芽率、发芽势和发芽指数均达最大,萌发时滞和萌发历时最短,小苗的根最长,冠根长度比最大;变温处理的效果远不及恒温处理。此外,西双版纳曼么生产的种子质量较其它两个地方的好,可作为种源,而该地可作为勐腊毛麝香种子的繁殖地。 相似文献
7.
温度对紫椴种子萌发及萌发过程中物质转化的影响 总被引：2，自引：1，他引：1
为研究经层积处理解除休眠的紫椴种子适宜萌发的温度条件,及不同温度条件下种子萌发过程中储藏物质的动态变化,开展了紫椴在5种恒温和4种变温下种子的发芽率和发芽指数的研究,并选择萌发最适与最差温度重新进行发芽试验,探讨2种温度对种子萌发过程中储藏物质的转化的影响。结果表明：紫椴种子适宜萌发的恒温条件为10℃和变温条件为15℃/10℃,温度高于20℃时,温度越高,萌发率越低。不同温度下储藏物质转化研究表明,高温下,淀粉酶活性在一定程度上受到抑制,导致种子中的淀粉分解缓慢,可溶性糖和蛋白代谢也受到不同程度的抑制,从而导致种子不能正常萌发。 相似文献
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通过人工气候箱设置不同的温度条件,探讨了不同温度对车前属3种植物种子萌发的影响。结果表明,小车前和车前种子在恒温条件下发芽起始时间较相对应的变温条件快,变温15℃/25℃,25℃/35℃显著延迟萌发起始时间。小车前、车前和大车前种子萌发最适宜的变温环境为20℃/30℃,萌发率分别为83.60%、100.00%和98.80%,车前和大车前种子呈爆发型萌发方式,萌发率超过98%所需时间平均为4 d;恒温培养条件为25℃,且该温度下小车前种子全部萌发仅需3 d;高温均不利于种子萌发。3种车前属植物种子发芽势、发芽指数表现出与萌发率相一致的变化规律,表明3种车前属植物发芽势和发芽指数对温度的响应不同。 相似文献
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
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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
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
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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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[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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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