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1.
Fusarium head blight (FHB) caused by Fusarium spp. is one of the most important fungal diseases of wheat (Triticum aestivum L.) in regions with wet climatic conditions. Improvement of the FHB resistance by developing new varieties requires sound knowledge on the inheritance of resistance. An 8 × 8 diallel analysis was performed to estimate general (GCA) and specific (SCA) combining ability of resistance to FHB. The F1s and parental lines were evaluated under artificial inoculation at the experimental field of IFA-Tulln, Austria during 2001 and 2002. Disease severity was evaluated by repeated scoring of the percentage of infected spikelets and calculating an area under the disease progress curve (AUDPC). The analysis of combining ability across two years showed highly significant GCA and non-significant SCA effects indicating the importance of additive genetic components in controlling FHB resistance. The significant GCA-by-year interaction presented the role of environmental factors in influencing the FHB reaction of wheat lines. The comparison of the crosses with low FHB infection and GCA effects of their parents showed that such crosses involved at least one parent with high or average negative GCA effect. The results revealed that it is feasible to use highly or moderately resistant genotypes and conventional breeding methods to achieve genetic improvement of FHB resistance in spring wheat. 相似文献
2.
Summary
Fusarium oxysporum causes the most serious fungus disease in tulip. Breeding for resistant cultivars may considerably contribute to a solution of the problem.Bulbs of various cultivars planted in contaminated soil showed important and significant differences in resistance. Inoculation trials in the field and in the glasshouse have led to recommendations for the screening of juvenile and adult bulbs. 相似文献
3.
Summary Head blight caused by Fusarium culmorum and F. graminearum is damaging in all winter rye (Secale cereale L.) growing areas. For hybrid breeding, the relative magnitude of general (GCA) and specific combining ability (SCA) is a crucial parameter for developing appropriate selection procedures. Forty single-cross hybrids were produced by crossing six and seven inbred lines of the Petkus and Carsten gene pool, respectively, in a factorial design. Hybrids were evaluated in two years with artificial F. culmorum inoculation. Resistance traits were head blight rating and grain weight relative to the non-inoculated control. Both resistance traits were closely correlated across both years (r-0.8, P=0.01). Significant genotypic variation was found for both traits with medium to high estimates of heritability (h2=0.6-0.8). Components of variance for GCA were, across years, 10 and 6 times larger than those for SCA for head blight rating and relative grain weight, respectively. Significant SCA effects were found for 15 to 20% of all cross combinations across both traits in each year. SCA effects were, however, inconsistent over years leading to a high SCA-year interaction. In conclusion, resistance to Fusarium head blight among the interpool hybrids tested was conditioned mainly by additive gene action that could be utilized by recurrent selection in multi-environment trials.Abbreviations GCA
general combining ability
- SCA
specific combining ability 相似文献
4.
M. I. E. Arabi 《Euphytica》2005,145(1-2):161-170
Barley breeders in Syria attempting to develop barley (Hordeum vulgare L.) cultivars resistant to barley leaf stripe (BLS) disease caused by Pyrenophora graminea Ito & Kuribayashi [anamorph Drechslera graminea (Rabenh. Ex. Schlech. Shoem.)]. Information on the combining ability for BLS resistance in Syria is not available. This study
was conducted to evaluate, in 10 genetically diverse barley parents, general combining ability (GCA) and specific combining
ability (SCA) effects towards the determination of the genetic basis of disease resistance and to estimate genetic variability
for yield components and its modification by BLS. Ten parental genotypes varying in their reactions to BLS were crossed in
a half-diallel mating design to generate 45 full-sib families. The families and the parents were inoculated with P. graminea and evaluated for resistance in replicated field tests (three inoculated and three non-inoculated plots). The parents chosen
showed wide variations for resistance to BLS. Genetic component analysis showed significant effects for both GCA and SCA for
resistance to BLS, suggesting that additive as well as non-additive genetic mechanisms were involved in the expression of
resistance in these parents. GCA effects were more important than SCA effects. Resistant parents exhibited high negative GCA
indicating that additive gene effects were more predominant, and suggesting their prime suitability for use in barley breeding
programs to improve resistance to BLS. Narrow-sense heritability was 58% and broad-sense heritability was 99% indicating that
selection for BLS resistance should be effective in these crosses. A high genetic variability for the agronomic traits studied
was observed. Yield components decreased significantly in inoculated plants and more pronounced in diseased plants. Significant
GCA was observed for all traits. Values for GCA were, in some cases, significantly modified by BLS. This indicates that attention
must be paid to the danger of drawing conclusion in quantitative genetics studies dealing with both diseased and healthy plants.
Two genotypes, Banteng and Igri, had high negative GCA effects and are promising parents for enhancement of BLS resistance. 相似文献
5.
Wheat breeders in South Asia are attempting to develop wheat (Triticum aestivum L.) cultivars resistant to Helminthosporium leaf blight (HLB), which occurs mainly as a complex of spot blotch caused by Cochliobolus sativus (Ito & Kuribayashi) Drechs. ex Dastur, and tan spot caused by Pyrenophora tritici-repentis (Died.) Drechs. Information on the combining ability for HLB resistance in wheat cultivars of South Asia is not available. This study was undertaken to examine the resistance to HLB in nine genetically diverse wheat parents, and to evaluate their general combining ability (GCA) and specific combining ability (SCA) effects toward determining the genetic basis of disease resistance. Nine parents were crossed in a half-diallel mating design to produce 36 populations. The F1 and F2 progenies, and the parents were evaluated in replicated field tests at Rampur, Nepal. Multiple disease scores were recorded, and area under the disease progress curve (AUDPC) was calculated to measure disease severity over time. The combining ability analysis was performed using Griffing's Method 2, Model 1. The parents chosen showed wide variation for resistance to HLB. They and the F1 and F2 progenies differed significantly for AUDPC. GCA and SCA effects were significant in both generations suggesting that additive as well as non-additive genetic mechanisms were involved in the expression of resistance in these parents. Wheat genotypes 'SW89-5422', 'G 162', 'NL 781'and 'Chirya 7' had significantly negative GCA effects for AUDPC in both F1 and F2 generations, suggesting their prime suitability for use in wheat breeding programs to improve resistance to HLB. The estimate of narrow-sense heritability was 0.77 in both generations suggesting that selection for HLB resistance should be effective in these crosses. The results indicate a predominance of additive gene action in the inheritance of HLB resistance in spring wheat. 相似文献
6.
Summary Immature bulbs were used in two screening trials to identify daffodil genotypes resistant to basal rot disease caused by Fusarium oxysporum f. sp. narcissi. Progenies, having at least one parent with some resistance, were grown in compost infested with chlamydospores of the fungal pathogen, and survivors were recovered at final harvest. Survival rates were very low when one-year old bulbs were used; the greater survival of two-and three-year old bulbs indicates that resistance increased with bulb age. Selection pressure was influenced by inoculum concentration in the compost. Continuous variation of percentage bulb survival between progenies suggests a polygenic mode of inheritance; there was no evidence of maternal inheritance. Parental general combining ability (GCA) was highly significant and accounted for much of the difference in bulb survival between progenies, but non-additive parental effects were also apparent. GCA rankings in the two trials were similar and reflected the resistance of parental cultivars in the field. A three-dimensional graphing procedure was devised to depict goodness of fit of progeny data to the additive model. 相似文献
7.
Sweetpotato virus disease (SPVD) is due to the dual infection and synergistic interaction of Sweetpotato feathery mottle potyvirus (SPFMV) and Sweetpotato chlorotic stunt crinivirus(SPCSV), and causes up to 98% yield loss in sweetpotato in East Africa. This study was conducted to determine the inheritance
of resistance to SPVD in sweetpotato and to estimate the nature of genetic variance. Ten parental clones varying in reaction
to SPVD were crossed in a half diallel mating design to generate 45 full-sib families. The families were graft-inoculated
with SPCSV and SPFMV to induce SPVD and evaluated for resistance in a randomized complete block design at two sites in Namulonge,
Uganda during 1998–2000. In serological assays for SPFMV and SPCSV,resistance to symptom development and recovery from initial
systemic SPVD symptoms, characterised resistant genotypes. Genetic component analysis showed significant effects for both
general combining ability (GCA) and specific combining ability (SCA) for resistance to SPVD. GCA to SCA variance component
ratios were large (0.51–0.87), hence GCA effects were more important than SCA effects. Resistant parents exhibited high GCA
indicating that additive gene effects were predominant in the inheritance of resistance to SPVD and recovery. Narrow-sense
heritability (31–41%) and broad-sense heritability (73–98%) were moderate to high, indicating that rapid genetic gains for
SPVD resistance could be accomplished by mass selection breeding techniques. Two genotypes, New Kawogo and Sowola, had high
negative GCA effects and had several families in specific crosses,which exhibited rapid recovery from SPVD,and are promising
parents for enhancement of SPVD resistance and recovery.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
8.
The most effective strategy to control Fusarium head blight (FHB), a devastating disease of small‐grain cereals, is breeding resistant cultivars. This resistance study of F1 crosses, F2 and backcross generations of triticale estimates heterosis, general and specific combining ability (GCA, SCA), additive and dominance effects and compares parents with segregating generations. The genetic material consisted of 10 parents with their 45 F1 crosses and of six parents with their 15 F2 progeny and backcrosses to each parent. Genotypes were grown in various environments and artificially inoculated with an aggressive isolate of F. culmorum. FHB was assessed, by visual rating, as the mean of four to five individual ratings of disease development. Heterosis for FHB was of little importance. The correlation between the FHB rating of F1 crosses and their mid‐parent performance was close. GCA was the predominant source of variation, although the significance of the SCA variance also implied non‐additive allelic interaction. The preponderance of additive gene effects is encouraging for increasing resistance by a recurrent selection programme. The relationship between the GCA effect of a parent and its per se performance was close, which gives the possibility of predicting FHB resistance in F1 crosses. Additive effects were predominant in the F2 progeny and also in the backcrosses. Transgressive segregants could not be detected. Searching for them should be postponed to the F3 or later generations. 相似文献
9.
Summary All crosses, except for reciprocals, were made among ten cultivars originating from crop improvement programs in North Africa and the Middle East. The entries varied widely in reaction to Septoria tritici. F1 and F2 progenies of the crosses were evaluated using eight S. tritici isolates from seven countries in the Mediterranean area. Thus, sixteen separate combining ability analyses were excecuted. General combining ability (GCA) was the major component of variation, although specific combining ability (SCA) was present in most cases. Additive variance thus appears to be of predominant importance. Nevertheless, non-additive variance may interfere when line selection in a breeding program is practiced. While differing greatly among cultivars, specific GCA effects for each cultivar separately were of similar magnitude for all isolates. Ranking statistics determined that cultivars were ranked in similar order for both means and specific GCA effects independent of the isolate used. Different isolates may therefore interact with similar or identical genetically controlled mechanisms in a particular cultivar. This could indicate the absence of differential gene-for-gene relationships and suggests that isolates vary in aggressiveness rather than in virulence. 相似文献
10.
This study was conducted to estimate the genetic effects on biomass yield in the interspecific hybrids between Brassica napus and B. rapa, and to evaluate the relationship between parental genetic diversity and its effect on biomass yield of interspecific hybrids.
Six cultivars and lines of oilseed B. napus and 20 cultivars of oilseed B. rapa from different regions of the world were chosen to produce interspecific hybrids using NC design II. Obvious genetic differences
between B. rapa and B. napus were detected by RFLP. In addition, Chinese B. rapa and European B. rapa were shown genetically differences. Plant biomass yield from these interspecific hybrids were measured at the end of flowering
period. Significant differences
were detected among general combining ability (GCA) effects over two years and specific combining ability (SCA) effects differences
were detected in 2000. The ratios of mean squares, (σ2
GCA(f) + σ2
GCA(m)) / (σ2
GCA(f) + σ2
GCA(m) + σ2
SCA), were 89% and 88% in 1999 and 2000, respectively. This indicates that both additive effects and non-additive effects contributed
to the biomass yield of interspecific hybrids and the former played more important role. Some European B. rapa had significant negative GCA effects while many of Chinese B. rapa had significant positive GCA effects, indicating that Chinese B. rapa may be a valuable source for transferring favorable genes of biomass yield to B. napus. Significant positive correlation between parental genetic distance and biomass yield of interspecific hybrids implies that
larger genetic distance results in higher biomass yield for the interspecific hybrids. A way to utilize interspecific heterosis
for seed yield was discussed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
11.
A Fusarium sp. root pathogen of lupin is the causal agent of the most important disease that affects the cultivation of white lupin
(Lupinus albus L.) in Egypt. The aim of our research was to investigate whether host resistance to Fusariumroot disease was available in Egyptian landraces ofLupinus albus. Five Fusarium isolates collected from white lupin samples in Egypt were tested with an Egyptian landrace and a French cultivar. The most
aggressive isolate was used to screen an additional 15 Egyptian landraces, two cultivars released in Egypt after selection
among landraces, one Polish cultivar, and two French cultivars. The assessment of host response to Fusarium was performed in a field, and under controlled conditions in a greenhouse pot experiment. Most landraces and the two Egyptian
cultivars showed better resistance with good accordance between field and pot experiment. This experiment showed that Egyptian
genetic resources of white lupin possess partial resistance to Fusarium root rot. Egyptian germplasm may be an alternative genetic source for incorporating partial resistance to Fusarium root rot into the breeding pools.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
12.
Daniel A. Presello Juliana Iglesias Grisela Botta Lana M. Reid Gladys A. Lori Guillermo H. Eyhérabide 《Euphytica》2006,147(3):403-407
Sources of resistance to Fusarium spp. are needed to develop maize hybrids resistant to the accumulation of fungal mycotoxins in the grain. In a search for
resistant germplasm in 1999 and 2000, a set of Argentinian maize populations was evaluated in Ottawa, Canada, for resistance
to ear rots after inoculation with local isolates of Fusarium verticillioides and F. graminearum. Sixteen of these populations, varying in observed resistance levels, were re-evaluated in 2003 and 2004 in Pergamino, Argentina,
using local isolates of the same fungi. Conidial suspensions of each fungal species were inoculated into the silk channel
of primary ears. Disease severity was assessed after physiological maturity using a scale based on the percentage of visibly
infected kernels. Genotype effect was more important than genotype-by-fungal species or genotype-by-fungal species-by-environment
interaction effects. In addition, disease severity levels associated with each fungal species were positively correlated (P < 0.05) (r = 0.90, r = 0.81, r = 0.87 and r = 0.53, in Ottawa 1999 and 2000, and Pergamino 2003 and 2004, respectively). Populations ARZM 01107, ARZM 07138, ARZM 10041,
ARZM 13031, ARZM 16002 and Pora INTA exhibited the highest and most stable resistance to both species. Considering that disease
resistance exhibited low specificity to the environment and to the fungal species in evaluations conducted in a wide range
of environments and with fungal isolates collected from different hemispheres, the most resistant populations are potential
sources of genes for stable resistance to these Fusarium spp. 相似文献
13.
B.I.G. Haussmann D.E. Hess I. Sissoko M. Kayentao B.V.S. Reddy H.G. Welz H.H. Geiger 《Euphytica》2001,122(1):99-104
Sooty stripe [Ramulispora sorghi (Ellis and Everhart) Olive and Lefebre] is a widespread foliar disease of sorghum [Sorghum bicolor (L.) Moench] in West Africa, responsible for grain yield losses up to 46%. We studied the inheritance of sooty stripe resistance
in a 9 × 9 sorghum F2-population diallel grown together with parent lines and checks in1996 under natural disease pressure at two locations in
Mali. The percentage of infected leaf area was determined twice over a two-week interval during the season. At the second
evaluation, the mean sooty stripe severity amounted to 13% infected leaf area at Samanko and 12% at Cinzana. The frequency
distribution of the entries was approximately normal for the mean disease severity, averaged across assessment dates and locations,
pointing to the involvement of multiple genes. With the data combined across the two locations, genetic differences among
lines and among F2 populations were highly significant. Genotype × location interaction variances were also significant but much smaller than
the genetic variances. Broad-sense heritability estimates were 0.92 for lines and 0.94 for the F2 populations, for the mean percentage infected leaf area across the two assessment dates. General combining ability effects
(GCA) determined most of the differences among the F2 populations. Specific combining ability effects (SCA), and the interactions of GCA or SCA with locations were also significant
but less important. Line performance per se was highly correlated with GCA. Because of the high heritability and predominance of additive effects, prospects are good
for the genetic improvement of resistance to sooty stripe in sorghum in Mali, using simple pedigree or recurrent selection
procedures.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
14.
For a better understanding of the inheritance of seed yield traits in Quinoa (Chenopodium quinoa) Willd., a half-diallelic crossing experiment with six diverse but uniform breeding lines was conducted. True hybrid plants
were detected by means of differences in panicle colour in 14 out of the 15 crosses performed. The agronomic performance of
14 F2 populations and six parental lines was evaluated in field trials on fertile clay soil. General and specific combining ability
of the lines (GCA and SCA) were estimated. Highly significant differences in GCA effects were found between the lines for
plant height at maturity, early flowering, early maturity, seed yield and thousand seed weight. Significant SCA effects were
only found for plant height at maturity. However, SCA effects were rather small and accounted for 7% of the total variance.
The finding of large GCA effects and low SCA effects suggests that best selection results could be expected from crosses between
the agronomic best performing genotypes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
15.
Summary Calluses of spring and winter wheats (Triticum aestivum L.) were selected for Fusarium resistance in vitro, using the double-layer culture technique. Potato-dextrose agar medium in vials was inoculated with mycelia of Fusarium graminearum and F. culmorum. After one week, fungal cells were killed by autoclaving and the agar medium containing the thermostable toxic metabolites was overlayered with MS callus-growing medium. Later, wheat calluses were placed on the upper medium for 4–5 weeks, and from the surviving calluses plants were regenerated. R2 seedling populations from self-fertilized R1 plants of 4 varieties were tested for Fusarium resistance by artificial infections in the greenhouse, and 3% of the regenerated R2 plants have been found to be more resistant than the original cultivars. 相似文献
16.
Summary For genetic analysis of head blight in winter rye (Secale cereale) caused by Fusarium culmorum, six homozygous inbred lines from the Petkus gene pool were crossed in all combinations to obtain 15 diallel F1 crosses and the corresponding 15 F2 crosses. These materials and 10 additional inbreds were artificially inoculated in a 2-year field experiment. The inbreds were also tested with F. graminearum in a separate sub-experiment.Single disease rating, average disease rating, and yield components (grain-weight per spike, 1000-grain weight, kernel number per spike) relative to the non-inoculated treatment were significantly affected by Fusarium head blight in all material groups. The relative grain weight per spike ranged from 26% to 88%. Significant genotypic and genotype x year interaction variances were found throughout. Heritabilities were highest for homogeneous inbreds (h2=0.6–0.8) and lowest for heterogeneous F2 crosses (h2=0.4–0.6). Disease rating and relative grain-weight per spike were highly correlated for the inbreds and F2 crosses (r0.7, P0.01), but lower for the F1 crosses (r0.6, P0.05). Inter-annual correlation coefficients for disease ratings and relative grain-weight per spike ranged from r0.7 (inbreds) to r0.5 (F2 crosses). The diallel analysis showed significant GCA effects only for relative 1000-grain weight in 1990, but significant SCA and SCAx year interaction variances for most traits. The resistances of 16 inbreds to F. culmorum and F. graminearum were tightly associated for all traits (r=0.96–0.97, P0.01).In conclusion, only slow progress can be expected from selecting for Fusarium head blight resistance in rye due to the limited amount of additive genetic variance and the great improtance of environmental factors. 相似文献
17.
Combining ability of seed vigor and seed yield in soybean 总被引：4，自引：0，他引：4
Studies have shown no consensus in relationships between seed yield and vigor in soybean [Glycine max (L.) Merrill]. The lack of information regarding the inheritance of seed vigor prompted this study to determine the types
of gene action and combining ability estimates for seed vigor and its related traits. Five high and six low seed vigor soybean
genotypes were crossed in a diallel, and selfed to produce 55 F2 progenies, which were examined, along with the parents, for seed vigor, yield, and seed weight. Significant genotype and
environment effects were found for seed vigor and yield. General combining ability (GCA) effects for seed vigor and seed yield
were significant (p≤ 0.01) and larger than specific combining ability (SCA) effects. Significant GCA and SCA effects were found for seed weight,
indicating that both additive and non additive genetic effects were involved in conditioning seed weight. The ratios of mean
square, 2GCA / (2GCA+SCA), were 0.96 for seed vigor and 0.93 for seed yield. These ratios indicated that additive gene effects
were more important than non additive gene effects for seed vigor and seed yield in these crosses. Mean seed vigor(83.8%),
as determined by accelerated aging germination, and mean seed yield (2,155 kg ha-1)in high vigor × high vigor crosses were higher than the high vigor × low vigor and low vigor × low vigor crosses. Mean percent
accelerated aging germination rates in F2 populations from diallel crosses were significantly related to mid-parent seed vigor(r2 = 0.52**) and midparent seed size (r2 = 0.31**). These results indicated that levels of seed vigor can be improved through breeding, while maintaining high yields because
of the predominance of GCA effects in both seed vigor and seed yield.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
18.
Rebecca S. Zwart Hilde Muylle Johan Van Huylenbroeck Erik Van Bockstaele Isabel Roldán-Ruiz 《Euphytica》2008,162(3):449-456
The inheritance of Fusarium head blight (FHB) resistance was investigated in eight western European wheat lines using a half-diallel
of F1 crosses. The parents and F1 crosses were point-inoculated, with a highly aggressive isolate of Fusarium graminearum, in replicated field and glasshouse trials. Type II resistance was assessed by measuring the % FHB spread and % wilted tips.
There was a good correlation between the two disease parameters, % FHB spread area under the disease progress curve (AUDPC)
and % wilted tips AUDPC (r = 0.86, P < 0.01). Correlation coefficients between the field and glasshouse environments were r = 0.46 (P < 0.01) for % FHB spread AUDPC and r = 0.40 (P < 0.05) for % wilted tips AUDPC. Both general combining ability (GCA) and specific combining ability (SCA) effects influenced
the inheritance of FHB resistance, suggesting that in this set of parents both additive and non-additive (dominance or epistatic)
effects influence the inheritance of type II FHB resistance. Highly significant GCA-by-environment (P < 0.0001) and SCA-by-environment (P < 0.005) interactions were also observed. Specific combinations of western European wheat varieties were identified with
type II FHB resistance at a level equal to or more resistant than the winter wheat variety ‘Arina’. 相似文献
19.
Diallel analysis of resistance to head blight caused by Fusarium culmorum in winter wheat 总被引：1，自引：0，他引：1
C.H.A. Snijders 《Euphytica》1990,51(1):1-9
Summary Ten homozygous winter wheat genotypes representing different levels of resistance to Fusarium head blight were crossed in all possible combinations excluding reciprocals. Parents, F1 and F2 were inoculated with one pathogenic strain of Fusarium culmorum. Data for head blight, observed 21 days after first inoculation (OBS-2), and for the area under the disease progress curve, based on observations 14, 21 and 28 days after first inoculation (AUDPC), were analyzed. The contrast between parents and F1 crosses indicated dommance effects of the resistance genes. Diallel analysis according to Griffing's Method 4, Model 1 showed significant general combining ability (GCA) effects for both F1 and F2; specific combining ability effects were not significant. With the exception of one genotype for which general performance for Fusarium resistance was not in agreement with its GCA, the resistance to F. culmorum was uniformly transmitted to all offspring, and the parents can be described in terms of GCA. It is suggested that in the progenies with one of the awned lines as parent, one resistance gene was linked with the gene coding for presence of awns, located on chromosome 4B. A single observation date, taken at the right time, was as effective in assessing resistance as the AUDPC. 相似文献
20.
J. M. Van Tuyl 《Euphytica》1982,31(3):621-628
Summary Analysis of an incomplete diallel design with 14 hyacinth cultivars and 4 wild accessions of Hyacinthus orientalis showed a significant GCA component for resistance to yellow disease. The late flowering hyacinth cultivars King of the Blues and Marconi and the early flowering Hyacinthus orientalis 70129 were found to be the best combiners for yellow disease resistance. Within a cultivar, the degree of earliness itself was not associated with the degree of resistance. Correlation coefficients of leaf characters and degree of resistance showed that hyacinths with short and/or narrow leaves are generally more resistant than those with long and/or broad leaves. Tetraploid cultivars with few, large stomata tend to be susceptible, diploid ones with many small stomata tend to be the more resistant. 相似文献