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甜菜抗丛根病基因(Rz1)ISSR分子标记的初步研究 总被引：3，自引：1，他引：3
利用ISSR(简单重复间序列)技术对感病甜菜品种KVS3418及3个以KWS3418为轮回亲本的甜菜抗丛根病近等基因系进行分析，综合RAPD、SSR两种分子标记技术，经过多次重复，在一套ISSR引物中，筛选到与抗病性状相连锁的3个RAPD标记：Boya940、Boya800、Boya770。筛选到一个引物BA0061，在甜菜抗丛根病基因系间表现多态性。当用这个引物对已知的3个抗病材料及其它不舍此基因的感病材料进行检测时，多态性标记BA0061-1200，可从3个含抗丛根病基因的抗病材料中检测到1条12001bp的多态性带，而在其它感病材料中未出现。此标记可用于甜菜的分子育种。 相似文献
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甜菜抗丛根病机理研究初探 总被引：2，自引：1，他引：1
研究结果表明：甜菜抗丛根病类型品种与感病类型品种在发育的前、中、后期传毒介体多粘菌的含量差异均达极豆著水平（t〉0．01），而在同一抗性类型的品种间，甜菜在同一或不同的发育阶段，多粘菌的含量差异均不显著，多粘菌的含量与甜菜抗丛根病性呈极显著的负相关。初步认为：通过对甜菜多粘菌含量的分析，可以作为甜菜抗丛根病特性鉴定和品种选育的指标。 相似文献
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利用症状反应和RT-PCR技术对12个采自新疆不同地区的甜菜坏死黄脉病毒(BNYVV)分离物进行比较研究,结果表明:12个BNYVV分离物在甜菜、番杏和昆诺阿藜上的症状反应无明显区别,均以黄斑为主;利用RT-PCR进行的核酸组分分析却有一定差异,不同地区的BNYVV分离物含有不同的RNA组分,塔城地区、奇台地区及石河子145团的BNYVV分离物核酸组分为RNA1、RNA2、RNA3和RNA4;库尔勒地区的BNYVV分离物核酸组分还含有RNA5;石河子有些地区的BNYVV分离物核酸组分只有RNA1和RNA2。 相似文献
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为了更加准确地检测患有丛根病的甜莱植株中BNYVV病毒的含量。实验采用了RT-PCR的方法分别从26株待测甜菜的根中扩增获得了324bp的BNYVV病毒基因片断。通过调整反转录cDNA模板的浓度,研究发现,当cDNA模板稀释到100倍时．能更加精准地检测到不同丛根病染病植株中BNYVV病毒含量的差异。同时．半定量PCR的统计结果进一步表明．当待测植株中BNYVV病毒的相对含量低于阳性对照的一半时,甜菜丛根病病症并不明显;而当其相对含量超过阳性对照的1．3倍时,甜菜受害严重,有些几乎死亡。本检测方法为更加及时、快捷、准确和系统地检测甜菜植株的染病程度打下了良好的基础． 相似文献
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利用dsRNA介导的抗病性获得抗马铃薯Y病毒（PVY）的转基因烟草 总被引：1，自引：0，他引：1
为了获得抗马铃薯Y病毒(PVY)转基因烟草,分别扩增PVY HC-Pro基因3’端正、反向片段,构建反向重复植物表达载体.利用农杆菌介导法转化普通烟草(Nicotiana tabacum)云烟85,经抗性筛选及抗病性鉴定,获得T0代转基因抗病烟草株系.繁殖T0代抗病株系,抗病性鉴定发现,部分抗病株系的T1代烟株发生了一定比例的抗感分离.Real-time PCR检测发生抗感分离的T1代烟株,发现抗病烟株中PVY HC-Pro基因RNA积累水平显著低于感病烟株,说明抗病烟株中HC-Pro基因发生了RNA沉默.利用dsRNA技术沉默HC-Pro基因,获得了烟草品种云烟85的T1代转基因抗PVY株系. 相似文献
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Ourania I. PavliPiergiorgio Stevanato Enrico BiancardiGeorge N. Skaracis 《Field Crops Research》2011,122(3):165-172
Economic viability of a sugar beet crop largely depends on its successful protection against rhizomania, a most devastating disease that causes severe losses in root yield, sucrose content and quality. Rhizomania disease is caused by Beet necrotic yellow vein virus (BNYVV), a virus present in most sugar beet growing regions being vectored by the widely spread soil borne protoctist Polymyxa betae Keskin. The only practical means to control the disease is the use of genetically resistant varieties and, to date, such resistance is mainly based on a dominant gene (Rz1) that when present confers a sufficiently high level of protection against BNYVV. However, the emergence of virus strains capable of compromising the resistance employed in commercial varieties as well as a possible spread of more pathogenic isolates threatens crop's protection efficiency in the future. All these point to the necessity for exploiting new and more effective genetic sources of rhizomania resistance, both by classical and molecular breeding approaches, a practice that is being pursued by the relevant breeding firms. This article critically reviews the various issues related to the disease and its management and particularly to the ones pertaining to pathogen genetic diversity, types of genetic resistance currently employed, as well as to novel biotechnological approaches aiming at the development of better resisting cultivars. 相似文献
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Two potato breeding selections were released by the United States Department of Agriculture, Agricultural Research Service on November 14, 1996, as germplasm that is highly resistant to current populations ofPhytophthora infestans (Mont.) deBary, the causal organism of potato late blight: B0718-3 and B0767-2. These two clones have been evaluated for their reaction toP. infestans in replicated plots at Presque Isle, Maine since 1990. B0718-3 is a netted white-skinned selection with good yields but low specific gravity. It is both male and female fertile and crosses readily with tetraploid Tuberosum. B0767-2 is a russet-skinned selection that is low yielding and low in specific gravity. It has not been successfully crossed; however, it may have some potential use in somatic hybridizations. Neither B0718-3 nor B0767-2 process into acceptable colored chips. Genetic material of this release has been deposited in the National Plant Germplasm System where it is available for research purposes, including development and commercialization of new cultivars. 相似文献
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Glandular trichomes: Enzymic browning assays for improved selection of resistance to the green peach aphid 总被引：1，自引：0，他引：1
Polyphenoloxidase (PPO) activity in the glandular trichomes of 32Solanum tuberosum ×S. berthaultii F3 hybrid clones differentially resistant to the green peach aphid,Myzus persicae (Sulzer) was determined. Within this population of segregating clones, aphid infestation levels varied 8-fold, while a 5-fold difference in glandular trichome PPO activity was observed. PPO activity and aphid resistance at three sample dates were correlated as follows: r = 0.38 (P = 0.05), r = 0.31 (P = 0.10), and r = 0.55 (P = 0.01), respectively. The total browning potential test (TBP), a modification of the PPO assay, was developed for use in screening for aphid resistance. The TBP procedure is rapid, inexpensive, and highly effective in identifying aphid resistant clones. 相似文献
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P. H. Li N. P. A. Huner M. Toivio-Kinnucan H. H. Chen J. P. Palta 《American Journal of Potato Research》1981,58(1):15-29
Breeding and selection for frost resistant potatoes with high yield and good quality is very promising. This has been demonstrated in a frost resistance breeding program conducted at the International Potato Center, Lima, Peru. Yield trials were conducted using selected frost resistant clones at various Andean locations at elevations from 3,200 to 3,900 meters (14). During the growth season, several hail storms and frosts occurred at these locations. These freezes (?3°C to ?4°C) were very useful in elimination of the undesirable clones under natural conditions. Clones with yield from 1 to 2 kg/plant have been selected. A yield of 1 to 2 kg/plant was superior to most common cultivars grown in the Andes. The difference in frost resistance between a resistant and sensitive type of potato is about 3 to 4°C.Solanum tuberosum is a sensitive type which, in most cases, can survive at about ?2.0°C. Evidence indicates that the difference in resistance to freezing injury is due to the genotype’s capability to tolerate freeze-induced dehydration and to withstand the aggregation of proteins under freezing stress. It is likely that freezing injury is caused primarily by the loss of membrane integrity and, therefore, that membrane thermal stability is paramount in the tolerance to freezing stress. 相似文献
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Pedro L. Gomez Robert L. Plaisted H. David Thurston 《American Journal of Potato Research》1983,60(5):353-360
The objectives of this study were to combine and increase the frequency of resistance to root-knot and bacterial wilt in potatoes.Solanum sparsipilum was used as the source of resistance toMeloidogyne incognita, M. javanica, M. arenaria, andPseudomonas solanacearum. Neo-tuberosum clones into which bacterial wilt resistance fromSolanum phureja had been transferred were also used. It was possible to transfer the resistance to the three species of root-knot fromS. sparsipilum to the Neo-tuberosum population. Two cycles of selection were made and the percentage of clones resistant toP. solanacearum in the last cycle was 16% over the previous cycle. All the clones resistant toM. arenaria were resistant toM. incognita andM. javanica. Two groups of selected clones were formed. Clones in both groups are resistant to root-knot and bacterial wilt. In one of them the two sources of resistance toP. solanacearum have been combined. 相似文献
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Summary This paper reports results of a 3-year evaluation of CIP advanced potato clones in a bacterial wilt-infested field (race 3)
in Peru. Clones resistant or moderately resistant to wilt were selected and all tubers harvested from each clone were tested
for latent infection byRalstonia solanacearum using a sensitive serological technique developed at CIP. A sampling strategy to estimate accurately the frequency of infected
tubers in the clones has been evaluated. This method will allow consideration of tuber latent infection as a new selection
criterion in breeding for resistance to bacterial wilt. Thirteen clones were found resistant to wilt in all three evaluations
(i.e.≤6% wilt), from which five had no wilt in all trials. However, all clones harboured latent infection in tubers averaging
30%. Analysing 30 tubers/clone provides an accurate estimation of the proportion of infected tubers with a high precision
level. 相似文献
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A three-year study was conducted from 1991 through 1993 to evaluate the field performance of potato clones that had been selected for resistance to wilt symptom development and stem colonization byVerticillium dahliae. The total yield, size distribution, and specific-gravity of these highly resistant clones were compared with standard cultivars and two parent clones with high Verticillium resistance and high yield, A66107-51 and A68113-4. Two groups of Verticillium resistant germplasm were selected in 1991. One group was the highly resistant progeny from a cross between A66107-51 and A68113-4. The second group consisted of hybrids between wild species accessions with high Verticillium resistance and cultivated diploid and tetraploid germplasm. Twenty-one out of 125 progeny clones from the A66107-51 × A68113-4 cross were highly resistant to Verticillium infection and were tested in yield trials for two years. Another eight selections had high Verticillium resistance but such low yield of seed tubers that they were tested only one year for yield. Eleven of the original 29 highly resistant selections were significantly lower in total yield than Russet Burbank. Only one clone was significantly higher in yield than RB, and none outyielded either of the resistant parents. Reddale and Century Russet had moderate to high Verticillium resistance, respectively. Both outyielded Russet Burbank and were comparable with the high yielding resistant parents. Of 15 interspecific hybrids tested in 1991, only four had sufficient yield to produce seed for yield trials and good wilt resistance after three successive seasons of evaluation. We concluded from this study that selecting at early stages of variety development strictly for Verticillium resistance is likely to be inefficient. Rather, selection should be for yield and other agronomic criteria in Verticillium infested fields. 相似文献
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Summary Using potato parental lines homozygous at a locus or loci controlling resistance to potato leafroll virus (PLRV) can give
advantages in the selection of resistant forms. In order to identify homozygous diploid clones their test-cross families were
evaluated. All the clones that were test-crossed expressed resistance in primarily- and secondarily-infected plants and etiolated
sprouts, and were derived from mating genotypes highly resistant to PLRV. Genotypes from test-cross families varied in resistance
to PLRV, and one family was found which had only resistant genotypes, suggesting that the resistant parent of this progeny
was homozygous at resistance loci. Evidence was gathered that resistance in some diploid clones may result from resistance
to virus multiplication as well as restricted virus transport from leaves to tubers. 相似文献
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Phytophthora pod rot (Ppr) disease caused by Phytophthora megakarya is the major constraint to cocoa production in Cameroon. The development of resistant varieties requires the use of effective resistance testing methods. The repeatability and reliability of the leaf disc and detached pod tests, as applied in selection activities in Cameroon, were studied. Repeatability of the tests was estimated by calculating the correlation (r) between resistance scores of clones, progenies and individuals within progenies in different inoculations rounds of the leaf disc and detached pod tests. Such correlations were generally significant for both tests. For the leaf disc test, as expected, correlations were lower for individuals within seedling progenies than for the average of seedling progenies or of clones. This suggests that a higher number of replicate observations are required for correct evaluation of individual seedlings than for evaluation of the average level of resistance of progenies. Observations carried out 5 or 7 days after inoculation was highly correlated, suggesting that scoring in the leaf disc test may be done only once at 5, 6 or 7 days after inoculation. In one experiment the ranking of leaf disc and detached pod inoculation test results could be compared statistically, with data being significantly correlated (r 0.78). The reliability of the tests was evaluated by the correlations between results of the tests and the level of field infection. These were generally positive and significant, for the leaf disc and detached pod test. A variation between mean scores of 5 and 8 in the detached pod test appeared to be related to a 40% difference in field infection with P. megakarya in years with medium disease pressure. However, correlations with field resistance were not always significant, suggesting the influence of uncontrolled environmental factors affecting field observations or the results in the screening tests. It is concluded that the leaf disc and detached pod tests, if applied under standardized conditions, can be of great value to speed up selection for Ppr resistance. 相似文献