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1.
Assessing progenies of potato for resistance to skin spot (Polyscytalum pustulans) in the glasshouse
Summary Crosses were made between six parents differing in susceptibility to skin spot and glasshouse-grown tubers from true seedlings
of the nine resulting progenies assessed for resistance to the disease. The assessment was evaluated by a two-year comparison
with the behaviour of field-grown tubers of the progenies and their parents. The correlations between progenies in the glasshouse
and field were r=0.911 and 0.753 and those between the mid-parental values and the progeny means were high (r>0.864), indicating
that parental differences were heritable. It is concluded that correlations were sufficient for glasshouse-grown tubers to
be used for assessing large numbers of progenies in genetical studies and for eliminating highly susceptible progenies at
an early stage in a breeding programme.
R.L. Wastie died 16.01.96. 相似文献
2.
Summary A technique is described which enables potato clones to be screened for resistance to both species of potato cyst nematode
(Globodera rostochiensis andG. pallida) and to blight (Phytophthora infestans) in the foliage during the winter and first spring following harvest of seedlings grown from true seed.
A container test, used to assess resistance to both species ofGlobodera in a mixed inoculum, is followed by an assessment of resistance to foliage blight, using the same plants in the glasshouse.
This screen can be completed in time for duplicate tubers of the resistant clones to be planted for multiplication in the
second growing season.
The close correlation between results obtained using this system and those predicted from the known inheritance of the characters
selected and the gain in efficiency achieved in breeding, are illustrated by examples.
In Kartoffelzuchtprogrammen müssen viele Eigenschaften berücksichtigt werden. Die Reihenfolge ihrer Selektion kann grossen
Einfluss auf die gesamte Arbeitsleistung haben. Dort wo die Aufspaltung der Nachkommenschaft bedeutsam ist, kann eine frühe
Selektion leicht erkennbarer Eigenschaften, wie Resistenz gegenüber Sch?dlingen und Krankheiten, die Populationsgr?sse wirkungsvoll
verringern. Dies k?nnte den starken Selektionsdruck auf Knolleneigenschaften als erste Hauptprüfung in Kartoffelzuchtprogrammen
ersetzen.
In dieser Arbeit wird eine Technik zur Prüfung auf kombinierte Resistenz gegenüber Kartoffelnematoden und Krautf?ule beschrieben,
und es werden die Ergebnisse für Nachkommen aus typischen Kreuzungen mitgeteilt (Tabelle 1). Die Nematodenresistenz wurde
mit Hilfe eines Gef?sstestes ermittelt, bei dem ein Inokulumgemisch aus Larven vonGlobodera rostochiensis undG. pallida verwendet wurde. Dies ergab die in Tabelle 2 dargestellten Befunde und eine Verteilung der Zystenproduktion, wie sie in den
Abbildungen 1A und 1B gezeigt wird. Diese Ergebnisse best?tigten, dass die nicht wiederholten Tests Reaktionen ergaben, wie
sie von der bekannten Vererbung der Eigenschaften erwartet wurden, und ein Chi-Quadrat-Test (Tabelle 2) ergab bei drei von
vier Familien, dass keine Abweichung von den erwarteten Verh?ltnissen für H1, von dem sich dieG. rostochiensis-Resistenz herleitet, vorlag. Eine vorkommende Abweichung (Tabelle 2, Familie 4) liess sich mit der ungenügenden Unterscheidung
der unreifen Zysten von beidenGlobodera-Arten erkl?ren. Bei der Selektion auf Resistenz gegenüber den beiden Arten ist diese Fehlerquelle unbedeutend.
Die als nematodenresistent ermittelten Pflanzen wurden in T?pfen bei hoher Luftfeuchtigkeit in einem Polythen-Tunnel in Gew?chshaus
angezogen und mit einer Zoosporensuspension aus einem Isolatkomplex vonPhythophthora infestans besprüht. Die Anf?lligkeit wurde ermittelt, indem die ungef?hre Blattfl?che der entstehenden nekrotischen L?sionen bewertet
wurde. Die Ergebnisse in Tabelle 3 und die Verteilung der resistenten Klone (Abb. 1C) weisen—wie erwartet—auf die polygene
Vererbung hin. Bei den angewandten Selektionsstufen erhielt man ungef?hr 15% der Nachkommen mit hinreichender Resistenz gegenüber
den drei vorgegebenen Eigenschaften. Die Teste wurden in der Lagerzeit der Knollen, die ursprünglich von S?mplingspflanzen
stammten, abgeschlossen, so dass sie in der der Aussaat nachfolgenden Saison ausgepflanzt werden konnten.
Dans les programmes de sélection de la pomme de terre, de nombreux caractères sont pris en compte et le choix de la succession
de leurs mesures a une forte importance sur l'efficacité globale du travail. Quand il y a ségrégation pour des caractères
importants et facilement mesurables comme la résistance aux ravageurs et aux maladies, on peut réduire le travail de maintenance
du matériel en réalisant des cribles précoces pour ces caractères. Ces tests peuvent être d'abord réalisés à la place des
tests de qualité, classiquement effectués en début de programme.
Les auteurs décrivent ici une technique de tests de résistance à la fois vis-à-vis des nématodes à kyste et du mildiou. Les
résultats de tests de descendance de quatre croisements sont détaillés. La résistance aux nématodes est mesurée par des tests
en conteneours dans lesquels le substrat est infesté par un mélange de larves infestantes deGlobodera rostochiensis et deG. pallida. On trouve les résultats globaux en Tableau 2 et les distributions exprimées en valeur relative du nombre de kystes neoformés
sont représentées en figures 1A et 1B. Malgré l'absence de répétitions, ces résultats sont en accord avec ceux espérés: le
{ie67-1} (Tableau 2) ne montre pas de différence significative pour 3 familles sur 4 avec les résultats théoriques quand c'est
la résistance due au gène H1 qui est mesurée. Le cas de non concordance (Tableau 2, famille 4) est explicable par une possible
confusion des espèces à la lecture. Cependant, cette source d'erreurs est peu importante quand la sélection est dirigée en
même temps contre ces deux espèces.
Les clones jugés résistants sont alors testés vis-à-vis dePhytophthora infestans. Ils sont placés en pots et cultivés en serre sous tunnel de polyethylène pour entretenir une forte humidité relative. Une
suspension de zoospores d'un isolat complexe est pulvérisée et la sensibilité est appréciée par la surface approximative des
lésions nécrotiques du feuillage. Les résultats du Tableau 3 et la distribution relative de la fréquence des clones résistants
confirment l'hérédité polygénique de la résistance au mildiou.
Environ 15% des familles sont ainsi retenues comme ayant un bon niveau de résistance aux deux espèces deGlobodera et àP. infestans. Les tests, réalisés en hiver, sont achevés à temps pour que les duplicatats, conservés à basse température, identifiés comme
résistants puissent être plantés au champ en temps utile, l'année qui suit les semis de graines. 相似文献
3.
Daisaku Okamoto Søren V. S. Nielsen Merete Albrechtsen Bernhard Borkhardt 《Potato Research》1996,39(2):271-282
Summary Transgenic cv. Folva potato plants expressing the coat protein gene of potato virus Y strain N (PVYN) were produced usingAgrobacterium tumefaciens mediated transformation. Forty independent transformants were selected for resistance screening. Four clones showed complete
resistance to mechanical inoculation with all the five PVY isolates tested: the PVYN isolate from which the coat protein gene was derived, two PVYO isolates, and two PVYNTN isolates. Two of the fully resistant clones contained only one copy of the transgene, demonstrating that it is possible by
genetic engineering to obtain highly virus resistant potato clones that can also be useful in future breeding programmes. 相似文献
4.
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
5.
Summary
Phytophthora infestans isolates collected in Poland in 1987–1995 were evaluated on detached leaflets of a differential series consisting of potato
genotypes possessing resistance genes R1–R11. On the same differentials was evaluated over three years a highly virulentP. infestans isolate MP 245.
Isolate MP 245 and those from natural populations ofP. infestans were seldom or inconsistently pathogenic to R5, R8 and R9. When leaflets of the differentials were infected with MP 245 the
lesions were often small and sporulation weak. A statistically significant interaction was found between years and pathogenicity
of MP 245 to individual differentials. Attempts to train the isolate MP 245 for pathogenicity to R9 were unsuccessful.
The variation in specific resistance of potato genotypes may complicate the evaluation of their resistance toP. infestans, as well as the evaluation of the virulence spectrum of natural fungus populations. This variation may be due to changes
in specific pathogenicity of the fungus or in specific resistance of the potato. Some differentials have a possibly useful
resistance toP. infestans. 相似文献
6.
Summary In 1983 and 1984 there were reports in Norway of more severe late blight infection than usual on tubers of cv. Pimpernel,
a cultivar without R-genes known to be somewhat resistant to both haulm and tuber infection. Results from routine tests confirmed
earlier experience that cv. Pimpernel shows stable resistance to tuber late blight, although the ranking of cultivars may
vary between years.
In experiments during three harvest seasons tubers of different cultivars were inoculated with isolates ofP. infestans obtained from stocks of cv. Pimpernel with severe tuber late blight and with other isolates. In these experiments the isolates
from cv. Pimpernel caused more rot on tubers of Pimpernel than did other isolates. 相似文献
7.
Summary Field-grown tubers of 22 progenies ofSolanum tuberosum L. generated in a crossing programme involving seven parents differing in resistance toFusarium coeruleum Lib. ex Sacc. andF. sulphureum Schlect. (=F. sambucinum Fuckel, teleomorphGibberella pulicaris (Fr.) Sacc.) were wound-inoculated with a cornmeal + sand culture of each pathogen. Parental genotypes were also included.
The mean lesion size of each progeny was compared in 2 years of tests, as well as with published data on glasshouse-grown
tubers. ForF. coeruleum there was a high correlation between years as well as with the glasshouse data, but no such correlations were apparent withG. pulicaris. Furthermore, parental and GCA values, as well as progeny means and mid-parent scores, also correlated highly forF. coeruleum but not forG. pulicaris.
Glasshouse-grown tubers of 11 wildSolanum spp. were also inoculated with both pathogens. Some resistance to one or other, or both, was apparent, particularly inS. chacoense. 相似文献
8.
Summary The tolerance of and resistance toGlobodera pallida of two potato progenies which segregated for these characteristics were assessed in pots in the glasshouse. The level of
tolerance varied widely between genotypes within the progenies, with several genotypes being significantly more tolerant than
the intolerant parent. The levels of resistance and tolerance in the progenies were not significantly correlated. No indications
were obtained that the ranking of genotypes for tolerance is influenced by the density ofG. pallida in the soil. The results confirm that selection for tolerance in aG. pallida resistance breeding programme is useful and feasible. 相似文献
9.
Bogdan Flis 《Potato Research》1995,38(2):199-210
Summary Segregation for extreme resistance to PVY was evaluated in progenies derived from crossing two extremely resistant potato
clones with parents differing in resistance. Resistance was evaluated after mechanical inoculation with PVYO and PVYN, and after graft inoculation with PVYO. Biological and serological tests (ELISA) were used for virus detection. The extreme resistance is governed by a single dominant
gene, but observed segregations deviated from the expected ratios. Considerable modifying effects were detectable, depending
on the potato genotype and virus isolate, for a significant excess of susceptible genotypes was observed in some progenies.
Moreover, genotypes with non-parental types of resistance to PVY were observed. 相似文献
10.
Summary Soft rot caused by Erwinia carotovora ssp. atroseptica is a major disease of stored potatoes. Since varietal resistance can
contribute to control, the work reported was designed to find new sources of resistance among related tuber-bearing Solanum
spp. True seeds were imported from two international collections and families were screened for resistance to tuber soft rot.
Forty-eight resistant clones were found in 21 out of 100 accessions. These clones will be used in breeding programmes at the
diploid or tetraploid level. 相似文献
11.
Bacillus thuringiensis cry1Ab gene confers resistance to potato againstHelicoverpa armigera (Hubner)
S. K. Chakrabarti A. D. Mandaokar A. Shukla D. Pattanayak P. S. Naik R. P. Sharma P. A. Kumar 《Potato Research》2000,43(2):143-152
Summary
Helicoverpa armigera is one of the important insect pests adversely affecting the yield of potatoes in India. A synthetic gene encoding the insecticidal
crystal protein (Cry1Ab) ofBacillus thuringiensis (Bt) has been introduced into five genotypes of potato usingAgrobacterium tumefaciens. Southern analysis of DNA from transgenic plants confirmed the integration and copy number of the transgene. Double-antibody
quantitative sandwich ELISA analysis demonstrated high levels of Cry1Ab protein expression in transgenic plants. Insect bioassays
on the leaves of transgenic plants showed considerable protection against the larvae ofH. armigera in terms of leaf area consumed and larval weight reduction. 相似文献
12.
Summary The majority of isolates ofFusarium avenaceum caused dry rot on potato tubers; many were as pathogenic asF. coeruleum. Pathogenicity ofF. avenaceum was not related to the plant species from which the isolates originated. Tubers of potato cv. Cara were more susceptible
than those of cvs Romano or Maris Piper. Temperature (5–15° C) had no effect on lesion depth but lesions tended to be slightly
wider at the lowest temperature. Two isolates (of 61) from wheat and white lupin had a moderate level of resistance to thiabendazole.
The results are discussed in relation to the control of dry rot in stored potato tubers. 相似文献
13.
A. J. Hilton H. E. Stewart S. L. Linton M. J. Nicolson A. K. Lees 《Potato Research》2000,43(3):263-271
Summary Optimum storage conditions to identify resistance to silver scurf among commercially grown potato cultivars were determined
in a series of experiments. Inoculation of field-grown tubers with a conidial suspension ofH. solani (concentration 104 conidia per ml of water) and incubation at 15°C with 95% RH for 1 month followed by 2 months at 85% RH produced the greatest
differences in disease severity between potato cultivars. Results with glasshouse-grown tubers were comparable with those
from field-grown tubers, indicating that the test could be used to identify resistance in wild species of potato and to understand
the inheritance of this resistance. 相似文献
14.
Effect of haulm treatments on the formation of microsclerotia ofVerticillium dahliae Kleb. on potato
Summary In four pot experiments, potato plants of cv. Element were artificially infected withV. dahliae. At an early and a late harvest haulms were killed chemically, by burning or by various other treatments, including cutting
them into pieces of different lengths and keeping the debris on the soil surface or covering with soil. After 4 weeks the
plant material was air-dried and the number of microsclerotia per mg was determined.
At the early harvest, in two experiments, the chemical treatment yielded more microsclerotia than the cutting treatments.
Covering colonised haulm tissue with non-sterilised soil was effective in inhibiting microsclerotia formation. Shorter haulm
pieces led to fewer microsclerotia at the later harvest if the material was kept on the soil surface. The variation in microsclerotial
yield and in treatment effects among the different experiments was large. 相似文献
15.
Summary The relationship between resistance to late blight in foliage and tuber was examined on 50 clones of each of five progenies
from crosses where one parent was resistant in both foliage and tuber and the other susceptible. Foliage resistance was assessed
in a field trial and tuber resistance in a laboratory test on glasshouse-grown tubers. The genetical and environmental components
of variance and the phenotypic and genetical correlations between foliage and tuber blight scores were determined for each
progeny. Foliage and tuber resistance were correlated, indicating either that both are determined by the same genes or by
different linked genes.
The environmental component of variation was greater for tuber blight than foliage blight. We suggest that the most effective
way of selecting for resistance to both aspects of the disease in a breeding programme is to select those resistant in the
foliage and then screen them for tuber resistance. 相似文献
16.
New isolates of the necrotic strain of potato virus Y (PVYN) found recently in Poland 总被引:4,自引:0,他引:4
M. Chrzanowska 《Potato Research》1991,34(2):179-182
Summary In comparison to the previously known isolates of potato virus YN (PVYN), some isolates found in Poland since 1984 are more infectious to potato plants, reach faster a higher concentration and
induce milder disease symptoms.
Potato cultivars resistant to the standard type of PVYN may be susceptible to the new isolates whereas those that are extremely resistant to PVY remain extremely resistant to the
new isolates. The potato cultivar Elipsa is suitable for the differentiation of PVYN isolates. 相似文献
17.
Summary Accessions of tuber-bearingSolanum spp. related toS. tuberosum subsp.tuberosum were obtained from the German-Dutch collection (Braunschweig, Germany) and the Inter-regional potato collection (Sturgeon
Bay, USA). They were screened for resistance toG. rostochiensis Rol andG. pallida Pa2/3. Among 1567 clones from 52 accessions, 135 clones (23 accessions) were resistant toG. rostochiensis. They mainly representedS. andigena, gourlayi, spegazzinii andvernei. Among 1689 clones (74 accessions), 105 clones (32 accessions) were resistant toG. pallida. They representedS. gourlayi, spegazzinii, sparsipilum andvernei. About 25 clones were resistant to both species. 相似文献
18.
Summary The influence of freeze dried potato powder derived from tubers (cvs Désirée and Epicure) exposed to light as a culture medium
on the growth, number and spore size of nine fungal pathogens was determined in vitro with particular emphasis on the role
of glycoalkaloids. Greater reductions in pathogen growth reflected increased exposure to light of tubers prior to freeze drying.
High correlations (% R2 adj) were obtained between glycoalkaloid concentration and growth rate of the majority of pathogens tested. Where spores
were produced, numbers were in general significantly less when cultured on freeze dried powder derived from tubers exposed
to light. No effects on spore size ofFusarium species were recorded, but spore length of remaining pathogens was reduced and spore width increased, with the exception
ofC. coccodes where spore length and width was increased following culture onto freeze dried powder derived from tubers exposed to light. 相似文献
19.
Summary Increasing doses of nitrogenous fertilizer increased storage rots in six potato cultivars of which cvs Kufri Sindhuri and
Kufri Lalima rotted less and were found to contain high amounts of total phenols compared to the more susceptible cultivars
Kufri Jyoti and Kufri Badshah. Nine phenolic acids were identified in the peel and the pulp of tubers and four of these and
of other phenolic extracts from tubers suppressed the growth ofErwinia carotovora ssp.carotovora.
Research Publication No. 5811, Experiment Station, G.B.P.U.A. & T., Pantnagar 263 145, India. 相似文献
20.
Summary Potatoes were stored in three insulated bins having ventilation rates of 0.0190, 0.0306 and 0.0417 m3/s·t. The results showed that in the climate of northern Italy potatoes can be stored successfully at ventilation rates of
not less than 0.0306 m3/s·t resulting in product weight loss of less than 2.0% after 100 days' storage. The incidence of diseases and of sprouting
was very low at rates of 0.0306 and 0.0417 m3/s·t, but greater at 0.019 m3/s·t because of the higher tuber temperature. Laboratory tests simulating ambient conditions confirmed the validity of a thermodynamic
model simulating air-potato heat exchange. 相似文献