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1.
The intercellular peroxidase and chitinase activities of three wheat cultivars [Triticum aestivum L. cvs `Tugela DN', `Molopo DN' (Gariep) and `Betta DN'] containing the Dn-1 gene for resistance to the Russian wheat aphid (RWA) Diuraphis noxia (Mordvilko) and the corresponding near-isogenic susceptible cultivars (`Tugela', `Molopo' and `Betta') were studied under
conditions of infestation and non-infestation. The aim was to gain information on the mechanism of resistance. The resistance
response was induced by RWA infestation. Infestation rapidly induced the activities of both enzymes selectively in resistant
wheat to levels of magnitudes higher than those in susceptible wheat. The genetic background in which the Dn-1 resistance gene is bred played a role and the level of activity corresponded to the level of resistance. Immunologic studies
confirmed that the induction of enzyme activities was due to the induction of higher protein levels. These results indicate
that peroxidase and chitinase may have a role in insect resistance.
Received: 20 June 1997 / Revision received: 9 April 1998 / Accepted: 5 June 1998 相似文献
2.
The reactive oxygen species are involved in resistance responses of wheat to the Russian wheat aphid 总被引:2,自引:0,他引:2
The effect of Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko), infestation on the hydrogen peroxide (H(2)O(2)) content and NADPH oxidase (EC 1.6.3.1) activity was studied in the resistant (cv. Tugela DN) and near-isogenic susceptible (cv. Tugela) wheat (Triticum aestivum L.). The objective of this study was to investigate the involvement of the reactive oxygen species (ROS) during the resistance responses against the RWA. Infestation significantly induced an early accumulation of the H(2)O(2) and increase of NADPH oxidase activity to higher levels in the resistant than susceptible plants. Results of inhibitory studies using diphenylene iodonium (DPI), a suicide inhibitor of NADPH oxidase, strongly suggested a possible signalling role for H(2)O(2) during RWA resistance response by activation of downstream defence enzymes [intercellular peroxidase (EC 1.11.1.7) and beta-1,3-glucanase (EC 3.2.1.39)]. 相似文献
3.
Lintle M van der Westhuizen AJ 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(9-10):867-873
Elicitors are molecules which can induce the activation of plant defence responses. Elicitor activity of intercellular wash fluid from Russian wheat aphid, Diuraphis noxia (Mordvilko) infested resistant (cv Tugela DN), and susceptible (cv Tugela), wheat (Triticum aestivum L.), was investigated. Known Russian wheat aphid resistance related responses such as peroxidase and beta-1,3-glucanase activities were used as parameters of elicitor activity. The intercellular wash fluid from infested resistant plants contains high elicitor activity while that from infested susceptible plants contains no or very little elicitor activity. After applying C-18 reverse phase and concanavalin A Sepharose chromatography, elicitor active glycoproteins were isolated from the intercellular wash fluid of Russian wheat aphid infested resistant wheat. The elicitor-active glycoproteins separated into three polypeptides during sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isolated glycoproteins elicited peroxidase activity to higher levels in resistant than in susceptible cultivars. It was evident that the glycoproteins were probably a general elicitor of plant origin. Information gained from these studies is valuable for the development of plant activators to enhance the defence responses of plants. 相似文献
4.
Vesselina S. Anguelova Amie J. van der Westhuizen & Zacharias A. Pretorius 《Physiologia plantarum》1999,106(4):393-401
To investigate biochemical aspects of resistance conferred by the Lr35 gene for adult-plant resistance in wheat ( Triticum aestivum L.) to leaf rust, pathogen development was related to intercellular protein composition and β -1,3-glucanase (EC 3.2.1.39) activities at three growth stages in infected and uninfected resistant (RL6082 [Thatcher/ Lr35 ]) and susceptible (Thatcher) plants. Leaf rust symptoms produced by pathotype UVPrt9 of Puccinia recondita f. sp. tritici showed that resistance conferred by Lr35 was most effective at the flag leaf stage. Furthermore, fluorescence microscopy indicated that resistance was strongly associated with hypersensitive cell death of invaded tissue. According to polypeptide profiles, intercellular proteins with molecular masses of 35, 33, 31 and 26 kDa were constitutively present at higher levels in resistant than in susceptible plants at the flag leaf stage. Four intercellular proteins (35, 33, 32 and 31 kDa) serologically related to β -1,3-glucanase were present in resistant and susceptible genotypes during all stages of plant growth. Resistance was associated with high constitutive levels of β -1,3-glucanase activity. Susceptibility on the other hand was associated with low constitutive levels of β -1,3-glucanase, while high levels were induced by infection during more advanced stages of colonization. Our results suggest that β -1,3-glucanase is involved in the defense response controlled by the Lr35 gene. 相似文献
5.
A crucial function of antioxidative enzymes is to remove excess reactive oxygen species (ROS), which can be toxic to plant cells. The effect of Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko), infestation on the activities of antioxidative enzymes was investigated in the resistant (cv. Tugela DN) and the near-isogenic susceptible (cv. Tugela) wheat (Triticum aestivum L.). RWA infestation significantly induced the activity of superoxide dismutase, glutathione reductase and ascorbate peroxidase to higher levels in the resistant than in susceptible plants. These findings suggest the involvement of antioxidative enzymes in the RWA-wheat resistance response, which was accompanied by an early oxidative burst. The results are consistent with the role of ROS in the resistance response and the control of their levels to minimise toxic effects. 相似文献
6.
7.
Inoculation of different bean cultivars with Colletotrichum lindemuthianum race β results in a marked increase of β-1,3-glucanase and chitinase activities. The increase is much faster in incompatible than in compatible interactions. Induced β-1,3-glucanase (pI 9,5) differs from the constitutive β-1,3-glucanase (pI 4,5) of healthy plants. The induced enzyme can partly degrade, in vitro, the cell walls of C. lindemutianum. The possible role of these hydrolytic enzymes inplants defence is discussed. 相似文献
8.
M. Alagar S. Suresh D. Saravanakumar R. Samiyappan 《Journal of Applied Entomology》2010,134(2):123-131
Six rice genotypes showing susceptible and resistant reactions to brown planthopper (BPH), Nilaparvata lugens were studied for feeding‐induced changes in defence enzymes and pathogenesis‐related (PR) proteins. The high resistant genotypes PTB 33, ADT 45 and ASD 7 and moderately resistant genotypes CO 43 and KAU 1661 recorded the greater expression of defence enzymes peroxidase, polyphenol oxidase, phenylalanine ammonia lyase, total phenol and β‐1,3 glucanase in response to N. lugens feeding at 1 day after infestation (DAI) compared with susceptible genotype TN1. The greater activity of chitinase was observed in resistant cultivars at 3 DAI and the activity was sustained for more than 1 week compared with susceptible TN1. In conclusion, the current study revealed that these defence enzymes and PR proteins might attribute to the resistance mechanisms in rice plants against BPH infestation. 相似文献
9.
Microsatellite-based molecular diversity of bread wheat germplasm and association mapping of wheat resistance to the Russian wheat aphid 总被引:1,自引:0,他引:1
Genetic diversity of a set of 71 wheat accessions, including 53 biotype 2 Russian wheat aphid (RWA2)-resistant landraces and
18 RWA2 susceptible accessions, was assessed by examining molecular variation at multiple microsatellite (SSR) loci. Fifty-one
wheat SSR primer pairs were used, 81 SSR loci were determined, and 545 SSR alleles were detected. These SSR loci covered all
the three genomes, 21 chromosomes, and at least 41 of the 42 chromosome arms. Diversity values averaged over SSR loci were
high with mean number of SSR alleles/locus = 6.7, mean Shannon’s index (H) = 1.291, and mean Nei’s gene diversity (He) = 0.609. The three wheat genomes ranked as A > D > B and the homoeologous groups ranked as 7 > 3 > 1 > 2 > 6 > 5 > 4 based
on the number of alleles per locus. Xgwm136 on chromosome arm 1AS is the most polymorphic SSR locus with the largest number of observed and effective alleles and the
highest H and He. Among all 2485 pairs of wheat accessions, genetic distance (GD) ranged from 0.054 to 1.933 and averaged 0.9832. A dendrogram
based on GD matrix showed that all the wheat accessions could be grouped into distinct clusters. Most of the susceptible cultivars
(13/18) were clustered into groups that contains all or mostly susceptible accessions. Most of the U.S. cultivars belong to
a group that is distinguishable from all the different RWA2 resistant groups. Diversity analysis was also conducted separately
for subgroups containing 53 RWA2-resistant accessions and 18 RWA2-susceptible accessions. Association mapping revealed 28
SSR loci significantly associated with leaf chlorosis, and 8 with leaf rolling. New chromosome regions associated with RWA2
resistance were detected, and indicated existence of new RWA resistance genes located on chromosomes of all other homoeologous
groups in addition to the groups 1 and 7 in bread wheat. This information is helpful for development of mapping populations
for RWA2 resistance genes from different phylogenetic groups, and for wise utilization of the RWA-resistant germplasm in wheat
breeding programs. 相似文献
10.
《Journal of Plant Interactions》2013,8(1):434-439
Pathogenesis-related (PR) proteins are induced in response to pathogen attack. In the present study, the induction of PR proteins in response to the fungal pathogen Macrophomina phaseolina was investigated in 15-day- and 1-month-old plants of Vigna aconitifolia with resistant and susceptible cultivars. Inoculation of the fungal pathogen resulted in the enzyme activity gradually increased throughout the experimental period of 168 h compared to control. However, the activation of β-1,3-glucanase and chitinase was more rapid and to a greater extent in the resistant FMM-96 cultivar as compared to susceptible RM0-40 and CZM-3 cultivars. Furthermore, the western blot analysis revealed the presence of 33- and 30-kDa bands of β-1,3-glucanase and chitinase in induced moth bean plants, respectively. The possible implications of these findings as part of the general defense response of moth bean plants against the fungal pathogen (M. phaseolina) have been discussed. 相似文献
11.
The different resistance of cotton (Gossypium hirsutum L.) cultivars to crude toxin of Verticillium dahliae (VD) was correlated with the activities of chitinase and β-1, 3-glucanase in callus cells. The activities of chitinase and β-1, 3-glucanase in the callus cells treated with the VD-toxin were increased to the higher level at earlier time point in resistant cultivars than these in the susceptible cultivars. Exogenous salicylic acid (SA) induced the accumulation of chitinase and β-1,3-glucanase, which resulted in the resistance of callus cells to the VD. toxin. Western blot using a polyclonal antibody against β-1,3-glucanase identified 28 kD protein that was induced by VD-toxin, SA, or VD-toxin plus SA. 相似文献
12.
Activation of Glycosidases as a Consequence of Infection Stress in Fusarium Wilt of Tomato 总被引:1,自引:0,他引:1
Changes of β-1,3-glucanase, chitinase, β-1,4-glucosidase and N-acetylglucosaminidase activity have been investigated in relation to the development of symptoms and colonization by the pathogen in roots, stems and leaves of susceptible (‘Improved, Pearson’) and resistant (‘Improved Pearson VF11’) tomato plants infected by Fusarium oxysporum f. sp. lycopersici. Glycosidase activities increased after inoculation to different extents depending on the plant part and cultivar. Increases were always higher in susceptible than in resistant plants. Changes in the β-1,3-glucanase activity after inoculation were particularly large in stems of infected plants. In contrast, chitinase activity increased more in roots than in stems. The β-1,3-glucosidase and chitinase activity decreased slightly from the basal to the apical third of stems. The trend of changes of the glycosidase activity generally were well related with the severity of disease symptoms and the fungal colonization of basal stem segments. There was no evidence that the increase of glycosidase activity after the infection was directly related with the resistance to Fusarium wilt in tomato. 相似文献
13.
Karin Forslund Jan Pettersson Tomas Bryngelsson Lisbeth Jonsson 《Physiologia plantarum》2000,110(4):496-502
The effect of infestation by the birdcherry-oat aphid ( Rhopalosiphum padi L.), on induction of PR-proteins was investigated in barley ( Hordeum vulgare L.), using barley lines susceptible or resistant to R. padi. The PR-proteins PR-1a (unknown function), PR-5a (acidic thaumatin) and peroxidase (EC 1.11.1.7) were not affected, whereas one chitinase (EC 3.2.1.14) and 4 β -1,3-glucanases (EC 3.2.1.39) were induced by the aphid treatment. In the resistant breeding line CI 16145, but not in the susceptible cultivar Golf, accumulation of one basic chitinase and two acidic β -1,3-glucanases increased with time from 2 until 11 days after infestation, as determined by western blots, with antibodies raised against purified chitinase (PR-3a) and β -1,3-glucanase (PR-2a) from barley. By isoelectric focusing, two additional basic β -1,3-glucanases were detected, which increased after infestation in both the resistant and the susceptible barley. The basic chitinase was only detected at days 7 and 11 in the susceptible cultivar, but already at day 2 in the resistant line. The induction was localized to the infested leaf. The PR-proteins PR-3a and PR-2a were also induced by the fungal pathogen ( Blumeria [syn. Erysiphe ] graminis f. sp. hordei ), methyl salicylate and, to a lower extent, by wounding with tweezers and methyl jasmonate (MeJA). Needle wounding performed to mimic aphid stylet penetration did not induce chitinase or β -1,3-glucanase. It is concluded that the fungal pathogen and the aphid infestation induce both similar and different responses, and that the aphid induction is not due to wounding only. The different responses in resistant and susceptible lines indicate that the induced enzymes may play a role in the resistance against aphid infestation. 相似文献
14.
Overexpression of defense response genes in transgenic wheat enhances resistance to Fusarium head blight 总被引:2,自引:0,他引:2
Mackintosh CA Lewis J Radmer LE Shin S Heinen SJ Smith LA Wyckoff MN Dill-Macky R Evans CK Kravchenko S Baldridge GD Zeyen RJ Muehlbauer GJ 《Plant cell reports》2007,26(4):479-488
Fusarium head blight (FHB) of wheat, caused by Fusarium graminearum and other Fusarium species, is a major disease problem for wheat production worldwide. To combat this problem, large-scale
breeding efforts have been established. Although progress has been made through standard breeding approaches, the level of
resistance attained is insufficient to withstand epidemic conditions. Genetic engineering provides an alternative approach
to enhance the level of resistance. Many defense response genes are induced in wheat during F. graminearum infection and may play a role in reducing FHB. The objectives of this study were (1) to develop transgenic wheat overexpressing
the defense response genes α-1-purothionin, thaumatin-like protein 1 (tlp-1), and β-1,3-glucanase; and (2) to test the resultant
transgenic wheat lines against F. graminearum infection under greenhouse and field conditions. Using the wheat cultivar Bobwhite, we developed one, two, and four lines
carrying the α-1-purothionin, tlp-1, and β-1,3-glucanase transgenes, respectively, that had statistically significant reductions
in FHB severity in greenhouse evaluations. We tested these seven transgenic lines under field conditions for percent FHB disease
severity, deoxynivalenol (DON) mycotoxin accumulation, and percent visually scabby kernels (VSK). Six of the seven lines differed
from the nontransgenic parental Bobwhite line for at least one of the disease traits. A β-1,3-glucanase transgenic line had
enhanced resistance, showing lower FHB severity, DON concentration, and percent VSK compared to Bobwhite. Taken together,
the results showed that overexpression of defense response genes in wheat could enhance the FHB resistance in both greenhouse
and field conditions. 相似文献
15.
Microsatellite markers linked to six Russian wheat aphid resistance genes in wheat 总被引:14,自引:0,他引:14
X. M. Liu C. M. Smith B. S. Gill V. Tolmay 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(4):504-510
The Russian wheat aphid (RWA), Diuraphis noxia Mordvilko, is a serious economic pest of wheat and barley in North America, South America, and South Africa. Using aphid-resistant
cultivars has proven to be a viable tactic for RWA management. Several dominant resistance genes have been identified in wheat,
Triticum aestivum, including Dn1 in PI 137739, Dn2 in PI 262660, and at least three resistance genes (Dn5+) in PI 294994. The identification of RWA-resistant genes and the development of resistant cultivars may be accelerated through
the use of molecular markers. DNA of wheat from near-isogenic lines and segregating F2 populations was amplified with microsatellite primers via PCR. Results revealed that the locus for wheat microsatellite GWM111
(Xgwm111), located on wheat chromosome 7DS (short arm), is tightly linked to Dn1, Dn2 and Dn5, as well as Dnx in PI 220127. Segregation data indicate RWA resistance in wheat PI 220127 is also conferred by a single dominant resistance
gene (Dnx). These results confirm that Dn1, Dn2 and Dn5 are tightly linked to each other, and provide new information about their location, being 7DS, near the centromere, instead
of as previously reported on 7DL. Xgwm635 (near the distal end of 7DS) clearly marked the location of the previously suggested resistance gene in PI 294994, here designated
as Dn8. Xgwm642 (located on 1DL) marked and identified another new gene Dn9, which is located in a defense gene-rich region of wheat chromosome 1DL. The locations of markers and the linked genes were
confirmed by di-telosomic and nulli-tetrasomic analyses. Genetic linkage maps of the above RWA resistance genes and markers
have been constructed for wheat chromosomes 1D and 7D. These markers will be useful in marker-assisted breeding for RWA-resistant
wheat.
Received: 17 May 2000 / Accepted: 13 June 2000 相似文献
16.
The interactions between barley yellow dwarf virus (BYDV) and Fusarium head blight (FHB), caused by Fusarium graminearum, were studied in the two winter wheat cultivars (cvs.), Agent (susceptible to FHB) and Petrus (moderately resistant to FHB), using ultrastructural and immunocytochemical methods. Infections of wheat plants of both cvs. by BYDV increased susceptibility to FHB. BYDV infection caused numerous cytological changes in lemma tissue of both cvs. such as formation of vesicles in the cytoplasm, degradation of fine structures of chloroplasts of both cvs. and accumulation of large starch grains in the chloroplasts. Electron microscopical studies showed that the development of F. graminearum on spike surfaces was not affected in BYDV‐infected plants. After penetration and intercellular growth in lemma tissue, defence responses to Fusarium infections were markedly reduced in BYDV‐diseased plants compared to the tissue of virus‐free plants. At sites of contact of fungal cells with host tissue, depositions of cell wall material were distinctly less pronounced than in tissues of virus‐free plants of cv. Petrus. Detection of β‐1,3‐glucanases and chitinases in lemma tissue of cv. Agent revealed no appreciably increased accumulation of both defence enzymes in F. graminearum‐infected virus‐free and BYDV‐infected tissues compared to the non‐infected control tissue. On the other hand, in cv. Petrus, infection with F. graminearum induced a markedly enhanced activity of both enzymes 3 days after inoculation. The increase of both enzyme activities was less pronounced in BYDV‐infected plants than in tissue exclusively infected with F. graminearum. Cytological studies suggest that in contrast to the susceptible cv. Agent postinfectional defence responses may play still an important role in the resistance of the moderately resistant cv. Petrus to FHB. 相似文献
17.
Assessing cultivar resistance to Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae) using a phenotyping method under semi‐field conditions 下载免费PDF全文
The orange wheat blossom midge, Sitodiplosis mosellana (Géhin), can significantly reduce wheat yield. Growing resistant wheat cultivars is an effective way of managing this pest. The assessment of cultivar resistance in field trials is difficult because of unequal pressure of S. mosellana caused by differences in cultivar heading dates relative to the flight period of S. mosellana adult females and huge variations of egg laying conditions from 1 day to another. To overcome these hurdles and to expose all cultivars homogeneously to the pest, an assessment method of cultivar resistance was developed under semi‐field conditions. In 2015, the resistance of 64 winter wheat cultivars to S. mosellana was assessed. Few or no larvae developed in the ears of resistant cultivars, but in susceptible cultivars, large numbers of larvae developed. Seventeen cultivars proved to be resistant, whereas 47 were susceptible. The identification of new resistant cultivars offers more opportunities to manage S. mosellana. The phenotyping method is easy, cheap, efficient and reliable. It can be used to guide the breeding of new resistant wheat cultivars. Using specific midge populations, this method could also be used in research on new resistance mechanisms in winter wheat or in other cereal species. 相似文献
18.
采用细胞化学方法对小麦与条锈菌互作过程中过氧化物酶的分布及其活性大小进行了研究,结果表明:过氧化物酶主要分布于细胞壁和细胞间隙中;在未行接种的小麦叶片中,抗病品种和感病品种的过氧化物酶活性均比较低;条锈菌侵染后,诱导抗、感病品种叶片中的过氧化物酶活性升高,且抗病品种升高的幅度明显大于感病品种;感病品种中过氧化物酶活性在侵染位点附近细胞壁上表现升高,而抗病品种中该酶的活性在侵染点细胞以及远离侵染点的叶肉细胞的细胞壁和细胞间隙中均显著升高。高活性的过氧化物酶是小麦抗条锈性的生化标记和重要机制之一。 相似文献
19.
F. Qalavand M. Nasr-Esfahani J. Vatandoost D. A. Azarm 《Plant biology (Stuttgart, Germany)》2023,25(1):119-130
- In common root and crown rot (CRR), Bipolaris sorokiniana (Sace.) is one of the important in wheat, causing considerable yield losses globally. Sources of resistance can provide a feasible and effective method of control for plant disease management. However, knowledge on mechanisms of resistance is scarce.
- We screened 33 wheat genotypes against B. sorokiniana under greenhouse and field conditions. In addition, real-time quantitative PCR (qPCR) analysis using ten novel candidate gene markers, Cre3, EDS1, LTP5, PGIP, PR-1, PIEP1, TLP, UGT, Stb6 and PFT, was conducted on leaves and roots, along with changes in activity of antioxidant enzymes, peroxidase, catalase, β-1,3-glucanase, and phenolic content for their involvement in disease impact mechanisms.
- Lowest disease severity was in ‘Alvand’, followed by ‘Baharan’ and ‘Bam’ as resistant genotypes. Quantitative gene expression showed that, although the candidate defence genes were upregulated 1.24- to 3.5-fold in wheat roots and leaves inoculated with B. sorokiniana, they were highly regulated in resistant varieties ‘Alvand’, ‘Mehregan’ and ‘Bam’. Cre3, a resistance gene to cereal cyst nematode Heterodera filipjevi, was regulated in cultivars resistant to B. sorokiniana. Similar results were obtained for Stb6, a gene resistant to Septoria tritici blotch, EDS1 resistant to powdery mildew, Blumeria graminis, and the genes PR-1 and UGT resistant to leaf rust, Puccinia triticina. Antioxidant enzyme activity also showed the highest increases in resistant genotypes.
- In conclusion, the T. aestivum–B. sorokiniana interaction in resistant wheat cultivars uses defence-related genes and enzymes that protect wheat towards sustainable development. Further such studies will shed light on simultaneous resistance to other diseases in wheat cultivars.
20.
Krystyna Rybka Edward Arseniuk Janina Wiśniewska Konstancja Raczyńska-Bojanowska 《Acta Physiologiae Plantarum》1998,20(1):59-66
The activities of chitinase, β-1,3-glucanase, peroxidase and phenylalanine ammonia lyase, constitutive and induced by Stagonospora nodorum were examined in the 10 – 14 day old seedlings of three triticale and two wheat cultivars under controlled environmental
conditions and in flag leaves of two triticale cultivars in the field. Two S. nodorum isolates of different virulence were used. Both the constitutive and induced activities in triticale and wheat depended on
genotype and in triticale the effect of growth conditions was also evidenced. The constitutive activities of chitinase, β-1,3-glucanase
and peroxidase were several fold lower in flag triticale leaves in plants from the field than in the seedlings, growing under
controlled conditions, but induction in the infected flag leaves was significantly more pronounced. In triticale genotypic
differences in the response to infection were revealed only upon inoculation by S. nodorum isolate of higher virulence. The enzymatic activities increased several fold during successive days after the infection except
for phenylalanine ammonia lyase. Induction of this enzyme was only transient and the activity decreased 48 or 96 h after infection
when the activities of other enzymes were rising. In flag leaves in the field this activity was differentiated only after
infection with more a virulent strain.
A tendency appeared in triticale seedlings for association of the resistance to the pathogen with lower enzymatic constitutive
activities. This relationship became more evident in triticale infected by S. nodorum and may imply that although the investigated enzymes are certainly involved in general, non-specific defense mechanism, they
do not decide on the resistance to pathogen at least in the early stages of infection and cooperate with other factors in
the complex pathogen-plant interaction. One can also assume that the enzymatic activities are associated with severity of
infection rather than resistance to pathogen. 相似文献