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81.
云南省保山市2006年2月引进甜柿品种大秋和阳丰接穗,在当地进行高接试种。经初步观察,大秋表现早丰产、果大、果面无纵沟,品质极上等,明显优于当地主栽品种次郎;阳丰表现生长健壮、早丰产、果面纵沟不明显,果实商品外观优于次郎,但果肉品质与次郎大致等同。 相似文献
82.
83.
秦芋32号(原代号:康0102-5)是2000年以秦芋30号作母本,89-1优系作父本,有性杂交获得实生种子,经育种圃、鉴定圃选育而成。2011年3月申报国家农作物品种审定委员会待审,2011年10月通过审定。2007~2009年参加国家级马铃薯品种中晚熟西南组繁种及区域试验;2010年国家西南组生产试验平均产量1 443 kg/667 m2,比对照米拉增产12.5%。块茎干物质含量18.5%、淀粉含量11.8%,Vc含量14.2 mg/100 g,还原糖含量0.29%,粗蛋白含量2.1%。抗病性接种鉴定:中抗PVX和PVY,抗晚疫病。 相似文献
84.
覆膜甜椒干物质积累与养分吸收分配规律的研究 总被引:2,自引:0,他引:2
地膜覆盖栽培提高了土壤的供肥能力,促进了甜椒对养分的吸收。在甜椒整个生育过程中,土壤养分含量前期较高,以后逐减,与植株养分吸收强度成负相关。覆膜甜椒前期需肥较少,吸肥高峰出现在采收至采收盛期,此间养分供需存在尖锐矛盾。对覆膜甜椒增施半腐熟有机肥,磷、钾化肥与有机肥混合栽前全层施入,结果至采收期分次适当多追氮素化肥,将有助子产量的提高。 相似文献
85.
Accessions of Australian Nicotiana species suitable as indicator hosts in the diagnosis of plant virus diseases 总被引:2,自引:0,他引:2
P. Van Dijk F. A. Van Der Meer P. G. M. Piron 《European journal of plant pathology / European Foundation for Plant Pathology》1987,93(2):73-85
When screening the genusNicotiana for sensitive and differential hosts for a group of mechanically transmissible plant viruses with narrow host ranges, development of systemic symptoms was alsmost exclusively observed in species of three closely related sections of the subgenusPetunioides. These species wereN. miersii (sectionAcuminatae),N. bigelovii andN. clevelandii (Bigelovianae) andN. benthamiana, N. cavicola, N. ingulba, N. occidentalis, N. rosulata andN. rotundifolia (Suaveolentes). Except forN. benthamiana andN. clevelandii, which are already known for their large virus ranges, they are new experimental hosts that appeared very useful for detection of viruses and for differentiation of viruses that closely resemble each other in host range. Accessions of the same species often varied largely in local and systemic viral response. EspeciallyN. benthamiana-9,N. miersii-33 andN. occidentalis-37B (code numbers given by Tobacco Research Laboratory, Oxford, N.C., USA) are recommended for routine inoculation tests. The sensitiveSuaveolentes species mentioned are native to the arid parts of Australia. Collections of these species deserve attention in studies on virus diseases of unknown etiology where experimental hosts are lacking.Samenvatting In het genusNicotiana werden vatbare, gevoelige en differentiële toetsplanten opgespoord door toetsing van vooral de collectie van het Tobacco Research Laboratory (Oxford, N.C., VS) met een aantal virussen waarvoor weinig of geen bruikbare toetsplanten bekend waren. Systemische reacties werden bijna uitsluitend in soorten van drie nauw verwante secties van het subgenusPetunioides waargenomen. Deze soorten warenN. miersii (sectieAcuminatae),N. bigelovii enN. clevelandii (Bigelovianae) enN. benthamiana, N. cavicola, N. ingulba, N. occidentalis, N. rosulata enN. rotundifolia (Suaveolentes). Behalve voor virusvermeerdering bleken deze soorten ook zeer geschikt te zijn voor differentiatie van virussen of virusstammen met een bijna gelijke waardplantenreeks.Collectienummers van één en dezelfde soort konden sterk in lokale en systemische reactie verschillen. VooralN. benthamiana-9,N. miersii-33 enN. occidentalis-37B kunnen voor routine-inoculaties worden aanbevolen. Met uitzondering vanN. benthamiana enN. clevelandii zijn de genoemde soorten of genotypen nieuwe experimentele waardplanten voor de virologie. De soorten die van de sectieSuaveolentes worden genoemd, zijn inheems in de woestijnachtige gebieden van Australië. Verzamelingen daarvan verdienen nadere aandacht bij de diagnostiek van virusziekten waarvoor nog geen experimentele waarplanten voorhanden zijn. 相似文献
86.
During the period 2000–03, local potato cultivars in Estonia, Latvia, Lithuania, Poland and Denmark were tested for foliar resistance to Phytophthora infestans (late blight) in an international field trial network. Four standard cultivars were included in the trials: Sava, Oleva, Danva and Kuras. Primary disease-assessment data were entered into a common database, and parameters from the disease progress curves were calculated and made available on interactive web pages. A regression model, using relative area under disease progress curve (RAUDPC) values for cv. Oleva as a reference, was developed for the estimation of 1–9 scale values, where 1 = most susceptible. Standard deviations for the estimated 1–9 scale values and a nonparametric rank stability analysis of RAUDPC were used to evaluate the stability of resistance of the cultivars. Overall, the results showed stability of resistance for cvs Sava, Oleva and Danva, but not for Kuras. Use of the Internet-based Web-Blight service in this study facilitated comparison of results among countries for the level and stability of resistance. The estimated 1–9 scale values were similar to, or slightly lower than, those from official cultivar lists or from the European Cultivated Potato Database, especially for the more resistant cultivars. Possible reasons for discrepancies from different sources and locations are discussed. It is concluded that RAUPDC and the derived 1–9 scale values are useful for ranking cultivars for resistance to P. infestans , but this information is not detailed enough for use in a decision support system for late blight control. 相似文献
87.
Riitta Nissinen Shaaban Kassuwi Riikka Peltola Mary C. Metzler 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(2):175-182
Clavibacter michiganensis subsp. sepedonicus, a Gram positive bacterium that causes bacterial ring rot of potato, was studied in eggplant, an alternate host, using strains that differed in phenotype. Two factors affecting virulence, the ability to induce a hypersensitive response (HR) and cellulase production, were studied. A plasmid-free isolate of C. michiganensis subsp. sepedonicus that causes HR on tobacco but is unable to produce cellulase multiplied efficiently in planta, but caused only weak symptoms. In contrast, a strain that is unable to induce HR on tobacco but produces cellulase was impaired in the ability to multiply in the host and caused no symptoms. When the two non-virulent strains were coinoculated into eggplants, typical disease symptoms developed. This enhancement was not due to formation of a new phenotype or significant increases in population density of either of the strains. Our results suggest that both cellulase production and the ability to induce HR are required for a successful infection process and disease induction by C. michiganensis subsp. sepedonicus. Our results additionally suggest that the ability to induce HR on non-host plants is required for multiplication in the host plant, whereas cellulase expression is necessary for induction of disease symptoms. 相似文献
88.
Evaluation and analysis of reduction of late blight disease in a diploid potato progeny 总被引:2,自引:0,他引:2
B. R. Trognitz † M. Orrillo L. Portal C. Román P. Ramón S. Perez G. Chacón 《Plant pathology》2001,50(3):281-291
The rate of late blight disease was analysed for individuals of a diploid Solanum phureja – Solanum tuberosum dihaploid hybrid population (PD), using three different assessment techniques, in the laboratory, screenhouse, and field. These hybrids expressed low disease rates in the field, comparable to resistance based on intact R genes. However, none of the parents of PD expressed any R genes and the pattern of segregation within the PD population was not indicative of R-gene inheritance. The foliage (or leaflet) area diseased had the largest broad-sense heritability of all criteria analysed, in all tests performed. In the field evaluations, the PD population showed intermediate levels of broad-sense heritability for foliage area diseased, relative to the much larger heritability detected for the group of controls possessing R genes. Resistance in the field of the PD hybrids had very little genotype-environment (G × E) interaction, indicating stability of its expression. All genotypes without R genes exhibited heritable, reduced rates of late blight disease in the field, but they were susceptible with low heritability in screenhouse and laboratory tests. This differential expression of disease indicates that the plants' indirect response to unknown environmental stress in the field may have been measured. The value of the PD hybrids for breeding of late blight resistant potato and the use of the disease rate data for detection of the underlying quantitative trait loci are discussed. 相似文献
89.
A 3-year field study examined the effects of 1,3-dichloropropene or oxamyl on tuber yields in four early- and five late-maturing potato cultivars. The nematicide treatments increased total tuber yield by ≈ 12% for early-maturing cultivars, but by less than 2% for the late-maturing cultivars. The treatments reduced the numbers of root lesion nematodes (primarily Pratylenchus penetrans ), which were the dominant plant parasitic nematodes at the site. Covariance analysis indicated that treatment effects on total tuber yield were no longer significant after adjusting for root lesion nematodes in soil at harvest, confirming that these nematodes had a direct effect on the host. As expected, there were significant inverse relationships ( P = 0·05) between total tuber yields and numbers of root lesion nematodes in soil and in roots. However, the application of nematicides in late-maturing cultivars was found to be of no practical value. Crop production systems designed to reduce or optimize pesticide applications can form one criterion in the development of more environmentally sensitive management strategies. The merit of utilizing chemicals for root lesion nematode control are considered with regard to cultivar maturity. 相似文献
90.
马铃薯纺锤块茎类病毒的检测和防治 总被引:5,自引:1,他引:5
马铃薯纺锤块茎类病毒病(potato spindle tuber viroid,PSTVd)是一种严重为害马铃薯生产的病害,降低产量20%—30%。防治的主要措施是应用无类病毒的种薯。由于目前还没有脱掉类病毒的有效措施,只能从未被饱和侵染的群体中鉴定筛选出未被侵染的个体,再脱掉其它病毒,作为核心繁殖材料。1987年以来,利用自制的电泳设备,以往复聚丙烯酰胺凝胶电泳法(return-polyacrylamide gel electrophoresis,R-PAGE)检测类病毒,筛选出未感病的个体,再用茎尖组织培养法脱掉其它病毒。经用马铃薯卷叶病毒等8种病毒酶标抗体鉴定筛选,获得既无类病毒也无主要马铃薯病毒的克新1、2、3和4号等主栽马铃薯品种的核心种。并已提供给省内外的良种场繁殖推广。1989和1990年抽样检测克山良种场繁殖的原种、一级和二级良种,未检测到类病毒。 相似文献