Genetics of resistance to five strains of turnip mosaic virus in Chinese cabbage   总被引：4，自引：0，他引：4  

S. K. Suh  S. K. Green  H. G. Park 《Euphytica》1995,81(1):71-77

Summary Inheritance of resistance to turnip mosaic virus (TuMV) strains C1, C2, C3, C4, and C5 in Chinese cabbage (Brassica campestris subsp. pekinensis) was evaluated using monoclonal antibodies. Crosses were made between a resistant line, 0–2, and four susceptible line. Seoul (SE),SSD31 (SS), Cheongbang (CH), and Yaki 1 ho (YA), to determine the inheritance of resistance of 0–2 in different genetic backgrounds. Resistance to TuMV was controlled by a single dominant gene or double dominant genes depending on the strain and cross. The resistance genes of 0–2 were modified by susceptible parents such that a single dominant gene was involved in the SS×0–2 combination, but double dominant genes in the SE×0–2 against TuMV-C3 or TuMV-C5. ELISA tests using inoculated and noninoculated leaves in the same plant suggested that the dominant resistance genes inhibit virus movement rather than virus multiplication.  相似文献   

Types and components of resistance to Fusarium head blight of wheat   总被引：18，自引：2，他引：18  

A. Mesterházy 《Plant Breeding》1995,114(5):377-386

Resistance of wheat to Fusarium head blight caused by Fusarium graminearum and F. culmorum was identified in natural epidemics in 1985 and 1987 as well after artificial inoculations (1983–1988 and 1984–1987). Out of 25 genotypes tested, five were identified with no significant difference in head blight scores, but differing significantly in yield after artificial inoculation, i.e. tolerance differences were detected at different resistance levels. Some genotypes that were similar in yield or head blight scores differed in seed infection severity. Genotypes with awns were more susceptible to head blight when tested under natural epidemic condition in the field; but this trait did not influence head blight severity in artificial inoculations. Dwarf genotypes were more severely infected by head blight than tall genotypes under natural conditions, but genotypes of different plant height classes were similarly susceptible after artificial inoculations. In the early generations of a breeding programme resistance measured by visual evaluation of artificial inoculation is the most important way to screen. If selection of dwarf and awned genotypes cannot be avoided, the higher susceptibility caused by awns and dwarfness under natural epidemic conditions can be decreased by a higher level of physiological resistance, as variability in physiological resistance is available. In later generations, traits like percentage of seed infection or tolerance can be identified by additionally measuring yield reduction. Stability of disease reaction appears to be connected with resistance level, the most resistant genotypes are the most stable, and the most susceptible ones tend to have more unstable reactions in different epidemic conditions.  相似文献   

甘蔗品种抗旱性光合生理指标及其综合评价   总被引：26，自引：0，他引：26  

高三基  罗俊  陈如凯  张木清  潘大仁 《作物学报》2002,28(1):94-98

利用相关、主成分、聚类和判别分析, 研究有关生理生化指标与甘蔗抗旱性关系. 结果表明: (1)中度水分胁迫下, MDA含量和PMP有不同程度地提高, 而Fv/Fm、 Fv/Fo、ΔFv/Fo、ΔFv/Ft和T1/2 有不同程度地降低, 变化的幅度因供试品种基因型而异. (2)PMP与MDA含量呈极显著正相关, 而与Fv/Fm、 Fv/Fo及ΔFv/Fo呈显著负相关; Fv/Fm与F  相似文献   

Research on Crack Resistance of the Roller Compacted Concrete     

《保鲜与加工》2002,(5):71-75

  相似文献   

播期对玉米早代自交系田间抗病性的影响   总被引：7，自引：0，他引：7  

张新  王振华  汪红 《华北农学报》2002,17(2):49-52

对1998－2000年4月中下旬（春播）和6月上旬（夏播）种植的1607份玉米早代系进行田间自然抗性鉴定表明：播期对玉米早代系田间抗病性具有很大的影响，玉米早代自交系大斑病和粗缩病以春播发生较重，而小斑病和茎基腐病以夏播发病较充分。因此，在鉴定玉米早代系田间抗性时应根据鉴定病害对象安排在不同播期进行。  相似文献   

Inheritance of tree and fruit characters in progenies from crosses of sweet cherry (Prunus avium L.) cultivars     

Robert Theiler-Hedtrich 《Euphytica》1994,77(1-2):37-44

Summary Approximately 1000 seedlings from 20 combinations crossed in 1979, 1980 and 1981 (Theiler-Hedtrich 1985a) were tested for several characters: fruit set (yield), fruit size, fruit colour, formation of abscission layer and bleeding after fruit removal from fruit stalks, bacterial canker resistance, flowering and harvesting time. From progeny of crosses with Stella as pollinator, 56% (Vittoria × Stella) and 46% (Schüttler × Stella) of the seedlings were self-compatible, of which 14 were high yielding with good fruit size and quality. From the data recorded it can be concluded:fruit set is a recessive character; only 5 to 20% of very good yielding seedlings were obtained in different progeny, even if the parental plants were both very good croppers.Fruit juice and skin colour was in most progenies ‘black’ even if they were from combinations with ‘white’ varieties, e.g., Merton Glory or Schüttler. Only from the combination Schiittler (‘white’) × Stella (‘black’), 50% of the seedlings were ‘white’; Stella therefore is heterozygous for the character of fruit juice and skin colour.Fruit size is evenly distributed in progeny with respect to the fruit size of their parent plants.Abscission layer formation and non-bleeding is a genetically complex character. In combinations where both parent plants formed fruits with complete abscission layers and which were not bleeding after fruit removal from the stalk, this character was inherited only to 50% (Vittoria × Schüttler) or 85% (Vittoria × Frühe von der Weid) in the progeny. For the genetical control of this character further studies are necessary.Bacterial canker susceptibility was evenly distributed in seedlings from all combinations even if the highly resistant cv. Vittoria was used as one parent plant, thereby not confirming the expected results of a higher proportion of resistant seedlings from combinations with Vittoria.Flowering and harvest time of the seedlings from different combinations was within the range of the parent plants. Only in the combination of Vittoria × Stella (mid-to late-ripening season) one seedling out of 99 was found to form ripe fruits two weeks earlier than the parental plants. From the seedlings tested 40 have been chosen for further evaluation or genetical studies.  相似文献   

Genetical relationships between reactions to bacterial leaf spot,yellow mosaic and Cercospora leaf spot diseases in mungbean (Vigna radiata)     

R. P. Thakur  P. N. Patel  J. P. Verma 《Euphytica》1977,26(3):765-774

Summary Studies on the inheritance pattern of bacterial leaf spot (BLS), yellow mosaic (YM) and Cercospora leaf spot (CLS) reactions in crosses of BLS and YM resistant/tolerant but CLS susceptible × CLS resistant but BLS and YM susceptible parents indicated that resistances to BLS and CLS were governed by single dominant genes, whereas YM tolerance was a monogenic recessive character. The studies also indicated that these three genes were inherited independently. The simple inheritance pattern and independent assortment of the genes governing resistance/tolerance to these diseases suggest that the usual breeding methods will be adequate to develop multi-disease resistant mungbean cultivars.Paper XII in the series Studies on resistance in crops to bacterial diseases in India.  相似文献   

Evaluation of a simple technique for characterizing rice root systems in relation to drought resistance   总被引：1，自引：0，他引：1  

J. C. O'Toole  Soemartono 《Euphytica》1981,30(2):283-290

Summary Drought is a constraint to rice yields in much of Asia's rainfed rice crop. Although genotypic variation for root system characteristics is well documented in this semiaquatic species, little improvement of rice for drought resistance has been attempted. No simple method to evaluate root systems exists. In this paper we report the development and testing of a simple device to measure the pulling force required to uproot rice seedlings. The force required to pull rice seedlings from the paddy soil was correlated with root weight, root branching and thick root number. The capability to separate rice cultivars by this technique and relationship of the root pulling force to other drought screening methods are illustrated.  相似文献   

Differential reaction of wheat cultivars to hot environments   总被引：3，自引：0，他引：3  

L. Shpiler  A. Blum 《Euphytica》1986,35(2):483-492

Summary Ten to 20 spring wheat (Triticum aestivum L.) cultivars of Israeli origin were grown in three winter (normal) and two summer (abnormal) growing seasons. During the period of emergence to anthesis mean daily temperature was on the average 12°C higher and photoperiod was about 3 h longer in the summer than in the winter. Data was collected on the durations of the periods from emergence to double-ridge (GS1), double ridge to anthesis (GS2) and anthesis to grain maturation (GS3), as well as on yield and yield components.The duration of all developmental stages was reduced by high temperature. While the duration of GS2 was the most thermo-sensitive, it may also have been reduced by the longer summer photoperiod. The effect of photoperiod on GS2 could not be isolated, but the results were interpreted to show that the effect of photoperiod on the duration of GS2 was relatively small.The most heat-affected yield component was number of grains per spikelet and the least affected component was the number of spikes per plant. High temperature reduced grain weight via reduced grain growth duration and not grain growth rate. A general linear regression model of yield on its components revealed that while variation for number of spikes per plant had the greatest effect on yield variation among cultivars in the winter, variation for number of grains per spikelet and spikelets per spike were by far the most important in the summer. Grain weight was the least important component, in this respect, in all seasons. Varieties which sustained the highest yield in hot environments were able to maintain the longest duration of GS2 and the highest number of grain per spike.  相似文献   

Genetics of resistance to ascochyta blight in chickpea (Cicer arietinum L.)     

S. K. Tewari  M. P. Pandey 《Euphytica》1986,35(1):211-215

Summary Six chickpea lines resistant to Ascochyta rabiei (Pass.) Lab. were crossed to four susceptible cultivars. The hybrids were resistant in all the crosses except the crosses where resistant line BRG 8 was involved. Segregation pattern for diseases reaction in F₂, BCP₁, BCP₂ and F₃ generations in field and glasshouse conditions revealed that resistance to Ascochyta blight is under the control of a single dominant gene in EC 26446, PG 82-1, P 919, P 1252-1 and NEC 2451 while a recessive gene is responsible in BRG 8. Allelic tests indicated the presence of three independently segregating genes for resistance; one dominant gene in P 1215-1 and one in EC 26446 and PG 82-1, and a recessive one in BRG 8.Research paper No. 3600  相似文献