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1.
黄瓜感染白粉病菌后的生理变化 总被引:8,自引:1,他引:7
抗性不同的黄瓜品种接种白粉病菌后,对与抗性有关的光合作用、呼吸强度及叶绿素、可溶性糖、可溶性蛋白质的含量进行了测定。结果表明:抗病品种呼吸强度比对照明显升高,感病品种则低于对照;抗、中抗品种光合速率先升高,5~6 d后开始下降,而感病品种的光合速率基本上低于对照,这与呼吸强度的变化相一致;无论抗病品种还是感病品种叶绿素含量均有增加,抗病品种增加幅度更大,说明黄瓜抗白粉病的能力与叶绿素含量呈正相关;接种后各品种糖含量的变化趋势基本一致,即降低-升高-再降低-再提高,而且均在第5 d出现第1个峰值,第7 d则出现最大幅度下降,可溶性糖含量明显低于对照,说明病菌的侵染消耗植株体内的糖,但并不能说明糖含量的降低与品种的抗病性密切相关;各黄瓜品种叶片可溶性蛋白质含量均高于对照,但感病品种比抗、中抗品种的峰值出现的要早,说明感病品种对病菌的侵染更敏感,品种的抗病性与对病菌侵染的反应呈负相关。 相似文献
2.
Impact of resistant melon cultivars on Sphaerotheca fuliginea 总被引:1,自引:0,他引:1
Effects of the resistant cultivars of melon on the powdery mildew fungus, Sphaerotheca fuliginea, were investigated in a melon‐growing area of Japan. Powdery mildew fungi were isolated from four melon cultivars (‘HN21’, ‘Quincy’, ‘Earl's Knight Natsu 2’ and ‘Earl's Miyabi Natsu 2′) which are resistant to different races of S. fuliginea.‘HN21’is resistant to races 1 and N1,‘Quincy’ and ‘Earl's Knight Natsu 2’are resistant to races 1 and N2, and ‘Earl's Miyabi Natsu 2’is resistant to races 1, N1 and N2. All 155 strains isolated from ‘HN21’were identified as race N2. Seventy out of 81 strains isolated from ‘Quincy’ and ‘Earl's Knight Natsu 2’were identified as race N1, while other strains were identified as races 1, 2US, N2 and N3. Nineteen out of 29 strains isolated from ‘Earl's Miyabi Natsu 2’were identified as race N3, while other strains were identified as races 10, 2US, N1 and N4. These results suggest that, although the resistant cultivars are extremely effective for protecting the plants from their respective races, a race succession rapidly takes place, even in a small area, and other minor races become predominant. 相似文献
3.
A study was conducted to investigate the expression of four components of partial resistance to Sphaerotheca fuliginea race 1 in selected melon (Cucumis melo L.) lines viz. infection frequency, latent period, spore production, and disease-severity score. Those components were evaluated at two developmental stages of the host: the cotyledon stage and the stage of the first two true leaves. Detached plant parts (disks of cotyledons and true leaves) were inoculated using a vacuum-operated settling tower. All four components showed significant variation among genotypes, and correlations between components at both developmental stages were large and significant. The line ‘CNPH 83–095’ (without any major resistance gene to powdery mildew) presented the highest level of partial resistance in both vegetative stages for almost all components evaluated. The lines ‘W-6’ (Pm1Pm1, Pm2Pm2), ‘Cinco’ (Pm1Pm1, Pm2Pm2), and CNPH ‘84–147’ (Pm1Pm1), even though carrying the major gene Pm1 for complete resistance to race 1 of the fungus, showed slight but significant differences for quantitative components of partial resistance at the cotyledonal stage. Different levels of partial resistance may be expressed, even in lines with a major race-specific resistance gene to powdery mildew, in specific developmental stages of the melon plants. 相似文献
4.
22种植物提取物对黄瓜白粉病菌的抑制作用 总被引:2,自引:0,他引:2
采用小株子叶法测试了22种植物提取物对黄瓜白粉病菌的抑制作用。其中水蓼、川黄柏、连翘等8种植物提取物对黄瓜白粉病菌具有较好抑制作用,EC50值均小于0.5%,除茵陈和马齿苋外,其他6种植物提取物对黄瓜白粉病的保护效果均高于治疗效果。8种植物提取物在1.25%浓度下对黄瓜白粉病的保护效果均高于化学药剂三唑酮100μg/mL(74.42%);1.25%的川黄柏、广藿香、马齿苋、蛇床子、南五味子提取物对黄瓜白粉病的治疗效果达到82%以上,高于三唑酮100μg/mL(78.89%),说明在黄瓜白粉病发生之前或初期使用这8种植物提取物能够达到较好的防治效果。 相似文献
5.
Race identification in powdery mildew (Sphaerotheca fuliginea) on melon (Cucumis melo) in Japan 总被引:1,自引:0,他引:1
Powdery mildew fungi isolated from single lesions on leaves of susceptible melon genotypes during semi-forcing and late-raising cultivation in Japan were tested. All 80 of the isolated strains were identified as Sphaerotheca fuliginea. The dominant fungus races found during semiforcing cultivation were race 5 in March (100%) and race 1 in May (100%), and race 1 (80%) during late-raising cultivation. Although the frequencies were quite low (13% in late August, but no isolation earlier in the season), two new races of S. fuliginea, which could not be identified by the differential genotypes, appeared during late-raising cultivation. These results suggest that the resistance gene to races 1 and 5 of S. fuliginea should be introduced into the breeding materials in Japan. 相似文献
6.
Summary The inheritance of resistance of three melon lines to Sphaerotheca fuliginea race 1 has been studied. Negro possesses one dominant gene for resistance. Resistance in Amarillo is mainly controlled by one gene, and resistance in Moscatel Grande seems to be controlled by two genes. These four genes are different from each other and allelism tests showed that the gene present in Negro is different from those described before in PMR5, PI 124111 and PI 124112. The main gene present in Amarillo is different from those carried by PMR5 and PI 124111 and the two genes carried by Moscatel Grande are different from the one present in PMR5. 相似文献
7.
几种化学诱导物对黄瓜白粉病抗性的诱导作用 总被引:17,自引:0,他引:17
在建立简单、有效、准确的叶圆片检测黄瓜白粉病抗性的基础上,系统地比较了7种化学诱导物及其组合对黄瓜白粉病抗性的诱导作用。结果表明,草酸、水杨酸、苦参碱、苯基硫脲、复合磷均能显著诱导黄瓜对白粉病的抗性。其诱导效果为草酸〉水杨酸〉苦参碱〉苯基硫脲〉复合磷,氯化钾和硫酸锰的诱导效果不明显。当苯基硫脲、苦参碱与硫酸锰、氯化钾和复合磷分别组合时与单一诱导物相比,诱导效果明显增强;而当水杨酸、草酸与之组合时诱导效果明显减弱,这可能与离子间相互作用有关。 相似文献
8.
Summary Among the genes for resistance against Sphaerotheca fuliginea, the gene s for resistance of the hypocotyl is linked to or identical with gene p for resistance to Pseudoperonospora cubensis. This gene s is present in the cultivars Ashley, Poinsett, Natsufushinari, Pixie, Taipei and in accessions PI 179676. PI 212233 and PI 234517.Although gene s initially brings about some resistance of the true leaf, it appears that when s is present. other genes are necessary for complete resistance to S. fuliginea. 相似文献
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10.
西葫芦胚囊再生植株倍性鉴定方法研究 总被引:7,自引:0,他引:7
利用根尖细胞染色体压片和叶片保卫细胞叶绿体压片方法对西葫芦胚囊再生植株进行了倍性鉴定,结果表明,单倍体、二倍体和四倍体植株叶片表皮保卫细胞叶绿体数的均值分别为(4.15±0.37),(8.05±0.76)和(16.05±0.69),其比例约为1:2:4,说明叶片保卫细胞叶绿体压片方法能有效用于倍性鉴定;单倍体、双单倍体和四倍体叶片表皮保卫细胞的长度分别为(20.31±3.38)μm、(30.80±2.19)μm和(41.78±1.03)μm,其比例约为1:1.5:2,在胚囊再生植株倍性鉴定时也可以参照。 相似文献
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13.
Cucurbita pepo (pumpkin, squash,gourd) is an economically important species that is susceptible to the cucurbit powdery mildew fungus, Podosphaera xanthii(syn. Sphaerotheca fuliginea). ‘True French’, an open-pollinated cultivar of the Zucchini Group of C. pepo, was crossed with an unnamed powdery-mildew resistant straight neck-type accession, the resistance of which was apparently
derived from an interspecific cross with a resistant wild species of Cucurbita,and resistant plants were selected in the F2 generation. This was followed by six cycles of backcross-pedigree selection for resistance, and resulted in the development
of an accession true-breeding for resistance to powdery mildew and nearly isogenic to ‘True French’. The resistant and susceptible
near-isogenics were crossed and seeds of the filial and backcross generations were produced. Plants of the parental accessions
and their progenies were grown together in a controlled-environment chamber, exposed to the pathogenic fungus, and scored
as resistant, partially resistant, or susceptible 27–33 days after sowing. The results indicated that resistance is conferred
by a single incompletely dominant gene, designated Pm-0.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
14.
Summary The genetic relation between powdery mildew resistance and sensitivity for leaf chlorosis of glasshouse cucumber was investigated. The powdery mildew resistant, leaf chlorosis sensitive hybrid variety Profito was crossed with the powdery mildew susceptible, non chlorosis sensitive hybrid variety Corona. Forty four F6 inbred lines of this cross, produced by single seed descent, were tested for powdery mildew resistance (PMR) and leaf chlorosis sensitivity (LCS). PMR and LCS were positively correlated (r=0.59). One or more of the PMR genes probably causes LCS as a pleiotropic effect or is closely linked to LCS, but also other factors, not genetically linked to PMR can cause LCS. Five F6 lines combined a significantly higher level of PMR than Corona with a significantly lower LCS than Profito. Three of these lines could hardly be distinguished from Corona for the level of LCS.Abbreviations LCS
leaf chlorosis sensitivity
- PMR
powdery mildew resistance
- SSD
Single Seed Descent 相似文献
15.
The Lack of a Relationship between Bitterness and Resistance of Cucurbits to Red Pumpkin Beetle (Aulacophora foveicollis) 总被引:2,自引:0,他引:2
N. P. S. Dhillon 《Plant Breeding》1993,110(1):73-76
Purified cucurbitacin B and E act as feeding stimulants for the red pumpkin beetle, but on testing three pairs of isogenic bitter (Bi) and non-bitter (bi) lines of cucumber, no relationship was found to exist between the bitter gene and the degree of damage caused by this beetle. In summer squash, both resistant and susceptible lines contain cucurbitacin at the susceptible plant growth stage (cotyledon) but there was no correlation between the quantity of total phenols, free amino acids or reducing sugars in this material and resistance. Bitter gourd, which has cucurbitacin in the cotyledons, was not preferred by the beetle. 相似文献
16.
Summary Cultivars of Cucurbita pepo were analyzed for their isozyme phenotypes by horizontal starch gel electrophoresis. Considerable allozymic variation was observed between cultivars, especially in the aspartate aminotransferase and malate dehydrogenase isozyme systems. Each of the five fruit types represented in the 21 cultivars tested (zucchini, pumpkin, spaghetti, acorn, scallop and yellow straightneck) could be distinguished by specific allozymes or combination of allozymes. Cultivars within a fruit type gave very similar allozyme phenotypes and often could not be distinguished on the basis of the 6 assays used. Despite the outcrossing nature of the species, allozyme polymorphism within most cultivars was low and did not seriously interfere with the analysis. Approximately half of the hybrid lines tested gave heterozygous phenotypes at one or more loci, indicating that such loci could be used to screen for the percentage of hybrid seed obtained from crosses. 相似文献
17.
Summary Bush and vine habit accessions and their reciprocal F1s of spaghetti squash (Cucurbita pepo) were compared for various vegetative and reproductive characteristics. Bush habit was dominant to vine. Vine plants produced more leaves, longer internodes, and more male flowers than did bush and F1 plants. Pistillate flowers developed at lower nodes in bush and F1 plants than in vine plants. Vine plants produced as much or more vegetative matter than did bush and F1 plants, but bush and F1 plants produced more fruits and greater yields than did vine plants. 相似文献
18.
Summary Powdery mildew development was assessed on squash (Cucurbita pepo) plants of a susceptible cultivar, a resistant accession, their F1, and their F2 in an early summer planting in the field, covered or not covered with a shading net. Three reaction types were observed: susceptible, powdery mildew on stems and on both, the upper and lower leaf surfaces, as in the susceptible parent; resistant, no powdery mildew on leaves or stems, as in the resistant parent; and partially resistant, powdery mildew on upper leaf surfaces only, as in the F1. Disease presence on the stem was associated with susceptibility. Shading hastened the appearance of powdery mildew and increased the severity of infection on partially resistant and susceptible plants, facilitating identification of resistant individuals in the F2 population.Contribution No. 1613-E from the Agricultural Research Organization, Bet Dagan, Israel 相似文献
19.
Condensed tannins (proanthocyanidins, PAs) in the seed meal of oilseed rape can potentially have a negative impact on non-ruminant
livestock nutrition, particularly because of their ability to form indigestible, astringent or bitter-tasting complexes with
proteins. One option to overcome this problem is the breeding of oilseed rape varieties with reduced condensed tannins in
the seed coat. This might be achievable via selection of genotypes with thinner seed coats and consequently reduced condensed
tannin accumulation (seed coat structural cell mutants), or alternatively by selection of genotypes with reduced biosynthesis
of condensed tannins (flavonoid biosynthesis mutants). Both types of transparent testa (TT) mutants are well-characterised
in Arabidopsis; however the genetic basis of the yellow-seed trait in the polyploid genome of rapeseed is still not completely understood.
In this study, genetic and chemical analyses of PAs were performed in 166 doubled haploid (DH) rapeseed lines from the segregating
Brassica napus doubled haploid population YE2-DH (black seed × yellow seed). Using these analyses, the relationship between seed colour
and PA fractions in B. napus was investigated with a view to improving the rapeseed meal quality. Proanthocyanidin contents were estimated by vanillin
and HPLC assays and the obtained values were used to identify quantitative trait loci. Closely linked molecular markers that
were identified during this study for the target traits (seed colour, condensed tannins) can be valuable tools for breeding
of new oilseed rape cultivars with reduced levels of antinutritive PA compounds. 相似文献
20.
The presence of glandular trichomes may protect alfalfa (Medicago sativa L.) against certain stem-, leaf-, and fruit-eating insect pests. In order to determine appropriate breeding methods to select for this trait, this study characterized quantitative genetic parameters of erect glandular trichome density in `KS94GH6' diploid (2n=2x=16) alfalfa. Eight female and five male plants were crossed in a Design II mating to produce 40 full-sib families. Glandular trichome density was determined on these families under replicated greenhouse conditions in Las Cruces and Los Lunas, New Mexico, U.S.A. The effect of males was significant (p 0.10) across the two environments. Variation among females was not significant within either location or across locations. The dominance genetic variance (2
D = 0.210) was greater than the additive genetic variance (2
A = 0.111). The average degree of dominance exceeded a value of `1' indicating that erect glandular trichome density in KS94GH6 may be influenced by digenic epistasis, and/or repulsion phase linkage disequilibrium. The large contribution of non-additiveeffects was reflected by a low narrow-sense heritability estimate (h
2
n = 0.25). The results indicate that further improvements in erect glandular trichome density in KS94GH6 alfalfa will require replicated progeny testing. Approaches to introgress this trait into cultivated tetraploid alfalfa are discussed. 相似文献