Interactions of the stripe rust pathogen (Puccinia striiformis f. sp responses. Among various genes involved in the plant-pathogen related (PR) protein genes determine different defense responses tritici) with wh...Interactions of the stripe rust pathogen (Puccinia striiformis f. sp responses. Among various genes involved in the plant-pathogen related (PR) protein genes determine different defense responses tritici) with wheat plants activate a w^ae range OT nost nteractions, the expressions of particular pathogenesis-Different types of resistance have been recognized and utilized for developing wheat cultivars for resistance to stripe rust. All-stage resistance can be detected in seedling stage and remains at high levels throughout the plant growth stages. This type of resistance is race-specific and not durable. In contrast, plants with only high-temperature adult-plant (HTAP) resistance are susceptible in seedling stage, but become resistant when plants grow older and the weather becomes warmer. HTAP resistance controlled by a single gene is partial, but usually non-race specific and durable. The objective of this study was to analyze the expression of PR protein genes involved in different types of wheat resistance to stripe rust. The expression levels of 8 PR protein genes (PR1, PRI.2, PR2, PR3, PR4, PR5, PR9 and PRIO) were quantitatively evaluated at 0, 1, 2, 7 and 14 days after inoculation in single resistance gene lines of wheat with all-stage resistance genes YrTrl, Yr76, YrSP and YrExp2 and lines carrying HTAP resistance genes Yr52, Yr59, Yr62 and Yr7B. Races PSTv-4 and PSTv-37 for compatible and incompatible interactions were used in evaluation of PR protein gene expression in wheat lines carrying all-stage resistance genes in the seedling- stage experiment while PSTv-37 was used in the HTAP experiment. Analysis of quantitative real-time polymerase chain reaction (qRT-PCR) revealed that all of the PR protein genes were involved in the different types of resistance controlled by different Yr genes. However, these genes were upregulated at different time points and at different levels during the infection process among the wheat lines with different Yr genes for either all-stage resistance or HTAP resistance. Some of the genes were also induced in compatible interactions, but the levels were almost always higher in the incompatible interaction than in the compatible interaction at the same time point for each Yr gene. These results indicate that both salicylic acid and jasmonate signaling pathways are involved in both race-specific all-stage resistance and non-race specific HTAP resistance. Although expressing at different stages of infection and at different levels, these PR protein genes work in concert for contribution to different types of resistance controlled by different Yr genes.展开更多
Pest damage is a significant factor that cuts agricultural production, and cultivation of pest-resistant varieties is the most economic and effective approach of controlling pest damage. Plant pest resistance includes...Pest damage is a significant factor that cuts agricultural production, and cultivation of pest-resistant varieties is the most economic and effective approach of controlling pest damage. Plant pest resistance includes antixenosis, antibiosis, and tolerance. Current popular methods for the genetic improvement of crop pest resistance are traditional breeding method, transgenic breeding, and molecular mark-assisted breeding. This paper introduced major mechanisms and genetic bases of plant pest resistance, "and reviewed research progress of domestic and international genetic improvement of plant pest resistance, analyzed the problems and its de- velopment prospects.展开更多
Background Cotton(Gossypium hirsutum L.)is one of the most significant fibre and cash crops and plays an important role in Indian industrial and agricultural economies.However,over the years quantity and quality have ...Background Cotton(Gossypium hirsutum L.)is one of the most significant fibre and cash crops and plays an important role in Indian industrial and agricultural economies.However,over the years quantity and quality have been hampered by the pest leafhopper.Leafhopper alone has been shown to cause yield losses of up to 40%.In this study,screening and evaluation were performed to identify and categorize 100 cotton genotypes along with 5 checks as resistant,moderately resistant,sensitive and highly sensitive to leafhoppers.Results A total of hundred genotypes were evaluated along with five checks for leafhopper resistance.Based on the screening results,a total of 19 genotypes were resistant to leafhoppers,which was on par with the findings of the check KC 3.The contents of total soluble sugar,total soluble protein,and total free amino acids were significantly positively correlated with the mean grade,whereas total phenols content and trichome density were significantly negatively correlated with the susceptibility grade.However,based on screening and biochemical analysis,the genotypes KC 2,JR-23,Samaru-26-T,D 4,TCH 1728,RS 253,and B-61-1862 exhibited high resistance to leafhopper.Conclusion According to the findings of this study,choosing genotypes with high total phenolics content together with high trichome density and low contents of total soluble sugar,total soluble protein,and free amino acids may aid in the development of resistant genotypes.展开更多
Plants have evolved complex mechanisms to defend themselves against pathogens. It has been shown that several defense responses are influenced by light, and the red/far-red light photoreceptor phytochromes (PHY) mod...Plants have evolved complex mechanisms to defend themselves against pathogens. It has been shown that several defense responses are influenced by light, and the red/far-red light photoreceptor phytochromes (PHY) modulate plant defense responses in Arabidopsis. Blue light receptor cryptochromes (CRY) work together with PHY to regulate many light-controlled responses, including photomorphogenesis, floral induction, and entrainment of the circadian clock. We report here that the Arabidopsis blue light photoreceptor CRY1 positively regulates inducible resistance to Pseudomonas syringae under continuous light conditions. By challenging plants with R syringae pv. tomato (Pst.) DC3000 carrying avrRpt2, we demonstrate that effector-triggered local resistance is down-regulated in the cry1 mutant, leading to more pathogen multiplication. In plants overexpressing CRY1 (CRYl-ovx), however, local resistance is significantly up-regulated. We also show that systemic acquired resistance (SAR) is positively regulated by CRY1, and that salicylic acid (SA)-induced pathogenesis-related gene PR-1 expression is reduced in the cry1 mutant, but enhanced in CRYl-ovx plants. However, our results in- dicate that CRY1 only modestly influences SA accumulation and has no effect on hypersensitive cell death. These results suggest that CRY1 may positively regulate R protein-mediated resistance to P. syringae with increased PR gene expression.展开更多
Chlorantraniliprole seed treatments in rice provide effective suppression of rice water weevil populations in the United States; however, heavy reliance on prophylac- tic insecticide treatments as a sole strategy coul...Chlorantraniliprole seed treatments in rice provide effective suppression of rice water weevil populations in the United States; however, heavy reliance on prophylac- tic insecticide treatments as a sole strategy could destabilize management programs for this insect. The present research evaluated the compatibility of seed treatments with two other potential management tactics--plant resistance and shallow flooding-by conducting two split-plot experiments in 2009 and 2011. In both experiments, no substantial antago- nism was found among the 3 different tactics. Statistical interactions in these experiments arose from the strong and persistent effects of chlorantraniliprole on larval densities rather than incompatibility of tactics. In 2009, weevil densities differed among varieties and were significantly lower on the cultivar "Jefferson." In 2011, weevil densities were reduced sig- nificantly in shallow-flooded plots compared to deep-flooded plots. Significant reductions in weevil numbers by chlorantraniliprole seed treatments, even at application rates 5 fold lower than commercially recommended rates, demonstrated the potential to reduce appli- cation rates of this highly potent larvicide. These latter results suggest that future studies on the relationship between chlorantraniliprole seed treatment rate and weevil fitness are warranted.展开更多
Environmental stresses caused by climate change have severely affected agriculture in the present century;Salinity and drought have challenged most forecasts for increased agricultural production in the past few decad...Environmental stresses caused by climate change have severely affected agriculture in the present century;Salinity and drought have challenged most forecasts for increased agricultural production in the past few decades,there-fore,different methods that reduce the effect of these stresses on plants have attracted scientists’attention.The effect of beneficial soil microorganisms on soil health and increasing plants’resistance to stresses is one of the solutions that researchers have paid attention to.This study investigated how Trichoderma species can be affected by the molecular and morphophysiological mechanisms of plants and improve their salt and drought resistance.This study also studied the different Trichoderma species’functions to get a better understanding of how they reduce salt and drought stresses.Furthermore,thefindings of this study provide a clear path for future research to focus on the unknown aspects of Trichoderma species andfind effective ways to boost crop production under environmental stresses.展开更多
Background:Sucking insect pests cause severe damage to cotton crop production.The development of insect resistant cotton cultivars is one of the most effective measures in curtailing the yield losses.Considering the r...Background:Sucking insect pests cause severe damage to cotton crop production.The development of insect resistant cotton cultivars is one of the most effective measures in curtailing the yield losses.Considering the role of morphological and biochemical host plant resista nee(HPR)traits in plant defense,12 cotton genotypes/varieties were evaluated for leaf area,leaf glanding,total soluble sugars,total soluble proteins,total phenolics,tannin and total flavonoids against fluctuating populations of whitefly,thrips and jassid under field conditions.Results:The population of these insects fluctuated during the growing seas on and remained above threshold level(whitefly>5,thrips>(8-10)f or jassid>1 per leaf)during late June and early July.Strong and negative association of whitefly(r=-0.825)and jassid(r=-0.929)with seed cotton yield was observed.Mean population of insects were the highest in Glandless-1 followed by NIA-82 and NIA-M30.NIAB-Kiran followed by NI AB-878 and Sadori were the most resistant,with the mean population of 1.41,1.60,1.66(whitefly);2.24,232,2.53(thrips)and 037,0.31,036(jassid),respectively.The resistant variety NIAB-Kiran showed less soluble sugars(8.54 mg.g^(-1)),soluble proteins(27.11 mg.g^(-1))and more phenolic(36.56 mg.g^(-1))and flavonoids(13.10mg.g^(-1))as compared with the susceptible check Glandless-1.Moreover,all insect populations were positively correlated with total soluble sugars and proteins.Whitefly populations exhibited negative response to leaf gossypol glands,total phenolics,tannins and flavonoids.The thrips and jassid populations had a significant and negative correlation with these four biochemical HPR traits.Conclusion:The ide ntified resistant resources and HPR traits can be deployed against sucking in sect pests'complex in future breeding programs of developing insect resistant cotton varieties.展开更多
World crop production requires highly-productive varieties of agricultural crops,which are resistant to pest organisms.Such varieties are also of great importance for the Uzbekistan.Their
In order to investigate the resistance of tea plant to tea aphid, the feeding behavior of tea aphids on six different tea cultivars was monitored by (EPG) technique. The result showed that the duration of El, E2 as ...In order to investigate the resistance of tea plant to tea aphid, the feeding behavior of tea aphids on six different tea cultivars was monitored by (EPG) technique. The result showed that the duration of El, E2 as well as (E I+E2) which was feeding waveforrns of Toxoptera aurantii (Boyer) in tea phloem was significantly different by variance analysis (P〈0.05) and so did the duration of the probing of T. aurantii in all the tea tissues. And the six tea cultivars were classified into three groups with cluster analysis, based on the six major parameters which were durations of np, C, El, E2, F, and G waveforms, then the six major parameters of these three groups were detected by variance analysis, and the rank of six different tea cultivars' resistance to T. aurantii from strong to weak was Zhongcha 108, Sucha 1, Anjibaicha, Longjing 43, Xicha 5, and Sucha 120. As this result was in accord with the investigation into the tea field, we concluded that EPG technique was one of the most important means to examine tea plant resistance to T. aurantii and the durations of waveform El, E2 and (El+E2) were important parameters for evaluating resistance of tea plants to tea aphids.展开更多
Pleiotropic drug resistance(PDR) transporters are widely distributed membrane proteins catalyzing the export or import of a diverse array of molecules, and are involved in many plant responses to biotic and abiotic st...Pleiotropic drug resistance(PDR) transporters are widely distributed membrane proteins catalyzing the export or import of a diverse array of molecules, and are involved in many plant responses to biotic and abiotic stresses. However, it is unclear whether PDRs are involved in Nicotiana attenuata resistance to the necrotic fungal pathogen Alternaria alternata. In this study, transcriptional levels of both NaPDR1 and NaPDR1-like were highly induced in N. attenuata leaves after A. alternata inoculation. Interestingly,silencing NaPDR1 or NaPDR1-like individually had little effect on N. attenuata resistance to A. alternata;however, when both genes were co-silenced plants became highly susceptible to the fungus, which was associated with elevated JA and ethylene responses. Neither NaPDR1 nor NaPDR1-like was significantly elicited by exogenous treatment with methyl jasmonate(MeJA), whereas both were highly induced by ethylene. The elicitation levels of both genes by A. alternata were significantly reduced in plants with impaired JA or ethylene signaling pathways. Thus, we conclude that both NaPDR1 and NaPDR1-like function redundantly to confer resistance against A. alternata in N. attenuata, and the elicitation of the transcripts of both genes by the fungus is partially dependent on ethylene and jasmonate signaling.展开更多
Cigar line Beinhart 1000-1 has effective durable resistance to black shank(BS) and is considered one of the most resistant sources in tobacco(Nicotiana tabacum L.). To investigate the inheritance and identification of...Cigar line Beinhart 1000-1 has effective durable resistance to black shank(BS) and is considered one of the most resistant sources in tobacco(Nicotiana tabacum L.). To investigate the inheritance and identification of stable quantitative trait loci(QTL) for BS response, F2,BC1 F2 individuals and BC1 F2:3 lines were produced from a cross between Beinhart 1000-1 and Xiaohuangjin 1025. Two major quantitative trait loci(M-QTL) named qBS7 and qBS17 were repeatedly detected under different conditions. QTL qBS7 was mapped to the region between PT30174 and PT60621 and explained 17.40%–25.60% of the phenotypic variance under different conditions. The other QTL qBS17 in interval PT61564–PT61538 of linkage group 17 was detected in a BC1 F2 population in the field and in BC1 F2:3 in both the field and at the seedling stage, explaining 6.90% to 11.60% of the phenotypic variance. The results improve our understanding of the inheritance of resistance to BS and provide information that can be used in marker-assisted breeding.展开更多
Plant viruses are a group of intracellular pathogens that persistently threaten global food security.Significant advances in plant virology have been achieved by Chinese scientists over the last 20 years,including bas...Plant viruses are a group of intracellular pathogens that persistently threaten global food security.Significant advances in plant virology have been achieved by Chinese scientists over the last 20 years,including basic research and technologies for preventing and controlling plant viral diseases.Here,we review these milestones and advances,including the identification of new crop-infecting viruses,dissection of pathogenic mechanisms of multiple viruses,examination of multilayered interactions among viruses,their host plants,and virus-transmitting arthropod vectors,and in-depth interrogation of plantencoded resistance and susceptibility determinants.Notably,various plant virus-based vectors have also been successfully developed for gene function studies and target gene expression in plants.We also recommend future plant virology studies in China.展开更多
The plant apoplast,which serves as the frontline battleground for long-term host–pathogen interactions,harbors a wealth of disease resistance resources.However,the identification of the disease resistance proteins in...The plant apoplast,which serves as the frontline battleground for long-term host–pathogen interactions,harbors a wealth of disease resistance resources.However,the identification of the disease resistance proteins in the apoplast is relatively lacking.In this study,we identified and characterized the rice secretory protein OsSSP1(Oryza sativa secretory small protein 1).OsSSP1 can be secreted into the plant apoplast,and either in vitro treatment of recombinant OsSSP1 or overexpression of OsSSP1 in rice could trigger plant immune response.The expression of OsSSP1 is suppressed significantly during Magnaporthe oryzae infection in the susceptible rice variety Taibei 309,and OsSSP1-overexpressing lines all show strong resistance to M.oryzae.Combining the knockout and overexpression results,we found that OsSSP1 positively regulates plant immunity in response to fungal infection.Moreover,the recognition and immune response triggered by OsSSP1 depend on an uncharacterized transmembrane OsSSR1(secretory small protein receptor 1)and the key co-receptor OsBAK1,since most of the induced immune response and resistance are lost in the absence of OsSSR1 or OsBAK1.Intriguingly,the OsSSP1 protein is relatively stable and can still induce plant resistance after 1 week of storage in the open environment,and exogenous OsSSP1 treatment for a 2-week period did not affect rice yield.Collectively,our study reveals that OsSSP1 can be secreted into the apoplast and percepted by OsSSR1 and OsBAK1 during fungal infection,thereby triggering the immune response to enhance plant resistance to M.oryzae.These findings provide novel resources and potential strategies for crop breeding and disease control.展开更多
The regulation of stomatal aperture opening and closure represents an evolutionary battle between plants and pathogens,characterized by adaptive strategies that influence both plant resistance and pathogen virulence.T...The regulation of stomatal aperture opening and closure represents an evolutionary battle between plants and pathogens,characterized by adaptive strategies that influence both plant resistance and pathogen virulence.The ongoing climate change introduces further complexity,affecting pathogen invasion and host immunity.This review delves into recent advances on our understanding of the mechanisms governing immunity-related stomatal movement and patterning with an emphasis on the regulation of stomatal opening and closure dynamics by pathogen patterns and host phytocytokines.In addition,the review explores how climate changes impact plant–pathogen interactions by modulating stomatal behavior.In light of the pressing challenges associated with food security and the unpredictable nature of climate changes,future research in this field,which includes the investigation of spatiotemporal regulation and engineering of stomatal immunity,emerges as a promising avenue for enhancing crop resilience and contributing to climate control strategies.展开更多
Rice is one of the most important staple foods for the world population,but it is attacked by a number of destructive pests.While evidence from greenhouse and laboratory tests has shown that silicon(Si)amendment can...Rice is one of the most important staple foods for the world population,but it is attacked by a number of destructive pests.While evidence from greenhouse and laboratory tests has shown that silicon(Si)amendment can confer enhanced resistance to pests in rice,few studies have directly demonstrated the Si-mediated protection from pests in a field situation.In this study,field plots with silicon amendments at 0,75,150 and 300 kg SiO2 ha-1 in early-and late-season rice were employed to evaluate the effects of silicon amendment on the occurrence of major insect pests and diseases and rice yield.Compared with the control plots without silicon amendment,plant damage by stem borer and leaf folder and population size of planthopper were significantly lower in three to five of the seven monitoring observations in each season in the plots amended with 300 kg SiO2 ha-1.The disease index of rice blast in the early-season rice was lower in the plots amended with Si at 300 kg SiO2 ha-1 than in the control plots,while Si protection from rice blast in the late-season rice and from rice sheath blight in the early-season rice were not apparent.An insignificant increase of rice yield by 16.4%(604 kg ha-1)was observed in the plots amended with 300 kg SiO2 ha-1 over the control plots.Our results indicate that Si amendment at 300kg SiO2 ha-1 can provide substantial protection from some of the rice pests under field conditions.These findings support the recommendation of silicon amendment as a key component of integrated management of rice pests.展开更多
In this study, a transgenic Bt maize hybrid (event MON 810 from Monsanto Company) expressing Cry1Ab protein derived from Bacillus thuringiensis (Bt) and its negative isoline hybrid were evaluated for control of the As...In this study, a transgenic Bt maize hybrid (event MON 810 from Monsanto Company) expressing Cry1Ab protein derived from Bacillus thuringiensis (Bt) and its negative isoline hybrid were evaluated for control of the Asian corn borer, Ostrinia furnacalis (Guenée) (Lepidoptera: Pyralidae), in a field trial. Maize plants were artificially infested with neonate larvae of Asian corn borer at the mid-whorl (first-generation), pre-tassel (first- and/or second-generation), and silk (second-generation) growth stages. The transgenic Bt maize hybrid sustained significantly less leaf feeding damage (rating 1.0±0.0) than its negative isoline control (rating 7.3±0.1). With the Bt maize, 1.36.8% of plants were damaged by corn borer tunneling with <0.5 cm tunneling per stalk under different levels of infestation, compared with 100% of plants damaged with 9.325.0 cm tunneling per stalk for the negative isoline control. On average, transgenic Bt maize hybrids had only 0.010.05 tunnels per stalk and no stems were broken. In contrast, the negative isoline control had 3.118.36 tunnels per stalk and 31.273.9% of stems broken. Yields were significantly higher in transgenic Bt maize than in the control. These results demonstrate that transgenic Bt maize can significantly minimize yield losses caused by the Asian corn borer through resistance to the first- and second-generation larvae.展开更多
In this research, supercritical carbon dioxide extraction (SFE) showed better extraction etlect when compared with Solid- liquid extraction (SLE), Soxhlet extraction (SEt and Ultrasonic extraction (UE), not onl...In this research, supercritical carbon dioxide extraction (SFE) showed better extraction etlect when compared with Solid- liquid extraction (SLE), Soxhlet extraction (SEt and Ultrasonic extraction (UE), not only in the rate but also the time. The comparison among these three extraction modifiers, including acetone, ethanol and methanol demonstrated that ethanol was preferred to SFE due to its high extraction effect and low toxicology. In addition, parameter of SFE, influence of temperature and pressure were investigated, and the best extraction effect was achieved at the optima conditions, temperature of 40℃ and the pressure of 35 MPa. Thus, SFE is a highly effective method for flavonols extraction, requiring minimum energy and producing non-toxic byproduct. SFE-GC system is applied for the evaluation on flavonols that plays a key role in plant resistance to heavy metal, with its content and synthetase gene expression significantly increasing in plant when threatened by heavy metal. Besides, results indicated that flavonols can improve plant resistance to oxidative stress by quenching the redundant ROS in matrix.展开更多
The aim of this study was to determine the allelopathic effects of <i><span style="font-family:Verdana;">Azadirachta indica</span></i><span style="font-family:Verdana;"&g...The aim of this study was to determine the allelopathic effects of <i><span style="font-family:Verdana;">Azadirachta indica</span></i><span style="font-family:Verdana;"> oil and aqueous extracts of </span><i><span style="font-family:Verdana;">Tithonia diversifolia</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Thevetia peruviana</span></i><span style="font-family:Verdana;"> on the growth and stimulation of metabolites involved in tomato plant resistance. Randomized in blocks within a shaded area, the different treatments prepared at 10% and 15% (v/v and w/v) in water were subsequently applied on tomatoes seeds to monitor the effect on germination, and on tomatoes leaves to monitor the effect on growth and resilience of the plants. The result showed that in stressful conditions all the treatment</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> significantly inhibit (p < 0.05) the germination capacity of the seeds from 21.22% to 92.61%, the germination rate from 39.82% to 92.76% and the germination viability of the seedlings from 64.67% to 100%. However, the negative allelopathic effect of the treatment was significantly reduced (p < 0.05) when used for germination initiation by botanical priming. In addition, while </span><i><span style="font-family:Verdana;">T. diversifolia</span></i><span style="font-family:Verdana;"> at 10% promotes a better aerial and root growth in tomato plants, </span><i><span style="font-family:Verdana;">T. peruviana</span></i><span style="font-family:Verdana;"> at 15% induces the activation of resistance mechanisms in tomato plants by increasing protein levels to 104.5%, phenol levels to 183.33% and peroxidase enzyme activity to 586.15%. Therefore, allelopathic compound of wild plants would be a good alternative for growth promotion and resistance of tomato crops.</span></span></span></span>展开更多
Cotton (Gossypium hirsutum L.) has epidermal glands containing terpenoid aldehyde (TA) compounds that protect the plant from pests and diseases. One TA, gossypol, has two forms (+) and (-) that are present in varying ...Cotton (Gossypium hirsutum L.) has epidermal glands containing terpenoid aldehyde (TA) compounds that protect the plant from pests and diseases. One TA, gossypol, has two forms (+) and (-) that are present in varying amounts. This study evaluated the variation in roots for TA compounds and how environment affected the levels of these compounds. Similar to seed, gossypol was the predominant TA in roots. No heliocides were detected with only trace amounts of other TAs, such as hemigossypolone or hemigossypol, detected in a few lines. Among the glanded lines, there were significant differences in gossypol content. Percent plus gossypol was consistently 4% - 10% higher in roots than seed. One line, “Mac7”, had 12 - 14 ug/mg gossypol in roots and 18 ug/mg in seed as well as >90% (+) gossypol in both roots and seed. Unlike other tissues in glandless cotton, the roots of glandless lines consistently produced detectable amounts of gossypol with 77% to 82% in the (+) form. Multi-year field tests showed that although gossypol levels in the roots were more affected by insect pressure or other environmental conditions than seed, there was selectable variation in upland cotton for root gossypol content. Unlike other parts of a glandless plant, the roots retained a functioning biochemical pathway for gossypol production.展开更多
基金supported by the U.S. Department of Agriculture, Agricultural Research Service (2090-22000018-00D)the Washington Grain Commission, USA (13C3061-5665)+2 种基金the Idaho Wheat Commission, USA (13C3061-5665 13C-3061-4232)The Fulbright fellowship
文摘Interactions of the stripe rust pathogen (Puccinia striiformis f. sp responses. Among various genes involved in the plant-pathogen related (PR) protein genes determine different defense responses tritici) with wheat plants activate a w^ae range OT nost nteractions, the expressions of particular pathogenesis-Different types of resistance have been recognized and utilized for developing wheat cultivars for resistance to stripe rust. All-stage resistance can be detected in seedling stage and remains at high levels throughout the plant growth stages. This type of resistance is race-specific and not durable. In contrast, plants with only high-temperature adult-plant (HTAP) resistance are susceptible in seedling stage, but become resistant when plants grow older and the weather becomes warmer. HTAP resistance controlled by a single gene is partial, but usually non-race specific and durable. The objective of this study was to analyze the expression of PR protein genes involved in different types of wheat resistance to stripe rust. The expression levels of 8 PR protein genes (PR1, PRI.2, PR2, PR3, PR4, PR5, PR9 and PRIO) were quantitatively evaluated at 0, 1, 2, 7 and 14 days after inoculation in single resistance gene lines of wheat with all-stage resistance genes YrTrl, Yr76, YrSP and YrExp2 and lines carrying HTAP resistance genes Yr52, Yr59, Yr62 and Yr7B. Races PSTv-4 and PSTv-37 for compatible and incompatible interactions were used in evaluation of PR protein gene expression in wheat lines carrying all-stage resistance genes in the seedling- stage experiment while PSTv-37 was used in the HTAP experiment. Analysis of quantitative real-time polymerase chain reaction (qRT-PCR) revealed that all of the PR protein genes were involved in the different types of resistance controlled by different Yr genes. However, these genes were upregulated at different time points and at different levels during the infection process among the wheat lines with different Yr genes for either all-stage resistance or HTAP resistance. Some of the genes were also induced in compatible interactions, but the levels were almost always higher in the incompatible interaction than in the compatible interaction at the same time point for each Yr gene. These results indicate that both salicylic acid and jasmonate signaling pathways are involved in both race-specific all-stage resistance and non-race specific HTAP resistance. Although expressing at different stages of infection and at different levels, these PR protein genes work in concert for contribution to different types of resistance controlled by different Yr genes.
基金Sponsored by Special Fund for Modern Agricultural Industry Technology System(CARS-09)Jiangsu Provincial Scientific and Technological Support Program(BE2013305)Program of Nantong Scientific and Technological Bureau(H2012014)
文摘Pest damage is a significant factor that cuts agricultural production, and cultivation of pest-resistant varieties is the most economic and effective approach of controlling pest damage. Plant pest resistance includes antixenosis, antibiosis, and tolerance. Current popular methods for the genetic improvement of crop pest resistance are traditional breeding method, transgenic breeding, and molecular mark-assisted breeding. This paper introduced major mechanisms and genetic bases of plant pest resistance, "and reviewed research progress of domestic and international genetic improvement of plant pest resistance, analyzed the problems and its de- velopment prospects.
文摘Background Cotton(Gossypium hirsutum L.)is one of the most significant fibre and cash crops and plays an important role in Indian industrial and agricultural economies.However,over the years quantity and quality have been hampered by the pest leafhopper.Leafhopper alone has been shown to cause yield losses of up to 40%.In this study,screening and evaluation were performed to identify and categorize 100 cotton genotypes along with 5 checks as resistant,moderately resistant,sensitive and highly sensitive to leafhoppers.Results A total of hundred genotypes were evaluated along with five checks for leafhopper resistance.Based on the screening results,a total of 19 genotypes were resistant to leafhoppers,which was on par with the findings of the check KC 3.The contents of total soluble sugar,total soluble protein,and total free amino acids were significantly positively correlated with the mean grade,whereas total phenols content and trichome density were significantly negatively correlated with the susceptibility grade.However,based on screening and biochemical analysis,the genotypes KC 2,JR-23,Samaru-26-T,D 4,TCH 1728,RS 253,and B-61-1862 exhibited high resistance to leafhopper.Conclusion According to the findings of this study,choosing genotypes with high total phenolics content together with high trichome density and low contents of total soluble sugar,total soluble protein,and free amino acids may aid in the development of resistant genotypes.
文摘Plants have evolved complex mechanisms to defend themselves against pathogens. It has been shown that several defense responses are influenced by light, and the red/far-red light photoreceptor phytochromes (PHY) modulate plant defense responses in Arabidopsis. Blue light receptor cryptochromes (CRY) work together with PHY to regulate many light-controlled responses, including photomorphogenesis, floral induction, and entrainment of the circadian clock. We report here that the Arabidopsis blue light photoreceptor CRY1 positively regulates inducible resistance to Pseudomonas syringae under continuous light conditions. By challenging plants with R syringae pv. tomato (Pst.) DC3000 carrying avrRpt2, we demonstrate that effector-triggered local resistance is down-regulated in the cry1 mutant, leading to more pathogen multiplication. In plants overexpressing CRY1 (CRYl-ovx), however, local resistance is significantly up-regulated. We also show that systemic acquired resistance (SAR) is positively regulated by CRY1, and that salicylic acid (SA)-induced pathogenesis-related gene PR-1 expression is reduced in the cry1 mutant, but enhanced in CRYl-ovx plants. However, our results in- dicate that CRY1 only modestly influences SA accumulation and has no effect on hypersensitive cell death. These results suggest that CRY1 may positively regulate R protein-mediated resistance to P. syringae with increased PR gene expression.
文摘Chlorantraniliprole seed treatments in rice provide effective suppression of rice water weevil populations in the United States; however, heavy reliance on prophylac- tic insecticide treatments as a sole strategy could destabilize management programs for this insect. The present research evaluated the compatibility of seed treatments with two other potential management tactics--plant resistance and shallow flooding-by conducting two split-plot experiments in 2009 and 2011. In both experiments, no substantial antago- nism was found among the 3 different tactics. Statistical interactions in these experiments arose from the strong and persistent effects of chlorantraniliprole on larval densities rather than incompatibility of tactics. In 2009, weevil densities differed among varieties and were significantly lower on the cultivar "Jefferson." In 2011, weevil densities were reduced sig- nificantly in shallow-flooded plots compared to deep-flooded plots. Significant reductions in weevil numbers by chlorantraniliprole seed treatments, even at application rates 5 fold lower than commercially recommended rates, demonstrated the potential to reduce appli- cation rates of this highly potent larvicide. These latter results suggest that future studies on the relationship between chlorantraniliprole seed treatment rate and weevil fitness are warranted.
基金supported by the Anhui Province Large-Scale Online Open Course(MOOC)Demonstration Project(2018mooc428)the Quality Engineering Project of Suzhou University:College of Geographic Information and Energy Agriculture Modern Industry(szxy2021cyxy06)+1 种基金the Key Project of Quality Engineering in Anhui Province(2021jyxm1499)the Scientific Research Platform Project of Suzhou University:Research Center of Non-Point Source Pollution Control and Ecological Remediation(2021XJPT11).
文摘Environmental stresses caused by climate change have severely affected agriculture in the present century;Salinity and drought have challenged most forecasts for increased agricultural production in the past few decades,there-fore,different methods that reduce the effect of these stresses on plants have attracted scientists’attention.The effect of beneficial soil microorganisms on soil health and increasing plants’resistance to stresses is one of the solutions that researchers have paid attention to.This study investigated how Trichoderma species can be affected by the molecular and morphophysiological mechanisms of plants and improve their salt and drought resistance.This study also studied the different Trichoderma species’functions to get a better understanding of how they reduce salt and drought stresses.Furthermore,thefindings of this study provide a clear path for future research to focus on the unknown aspects of Trichoderma species andfind effective ways to boost crop production under environmental stresses.
文摘Background:Sucking insect pests cause severe damage to cotton crop production.The development of insect resistant cotton cultivars is one of the most effective measures in curtailing the yield losses.Considering the role of morphological and biochemical host plant resista nee(HPR)traits in plant defense,12 cotton genotypes/varieties were evaluated for leaf area,leaf glanding,total soluble sugars,total soluble proteins,total phenolics,tannin and total flavonoids against fluctuating populations of whitefly,thrips and jassid under field conditions.Results:The population of these insects fluctuated during the growing seas on and remained above threshold level(whitefly>5,thrips>(8-10)f or jassid>1 per leaf)during late June and early July.Strong and negative association of whitefly(r=-0.825)and jassid(r=-0.929)with seed cotton yield was observed.Mean population of insects were the highest in Glandless-1 followed by NIA-82 and NIA-M30.NIAB-Kiran followed by NI AB-878 and Sadori were the most resistant,with the mean population of 1.41,1.60,1.66(whitefly);2.24,232,2.53(thrips)and 037,0.31,036(jassid),respectively.The resistant variety NIAB-Kiran showed less soluble sugars(8.54 mg.g^(-1)),soluble proteins(27.11 mg.g^(-1))and more phenolic(36.56 mg.g^(-1))and flavonoids(13.10mg.g^(-1))as compared with the susceptible check Glandless-1.Moreover,all insect populations were positively correlated with total soluble sugars and proteins.Whitefly populations exhibited negative response to leaf gossypol glands,total phenolics,tannins and flavonoids.The thrips and jassid populations had a significant and negative correlation with these four biochemical HPR traits.Conclusion:The ide ntified resistant resources and HPR traits can be deployed against sucking in sect pests'complex in future breeding programs of developing insect resistant cotton varieties.
文摘World crop production requires highly-productive varieties of agricultural crops,which are resistant to pest organisms.Such varieties are also of great importance for the Uzbekistan.Their
基金supported by the National Natural Science Foundation of China(31071744)the Natural Science Foundation of Zhejiang Province, China(Y3100375)
文摘In order to investigate the resistance of tea plant to tea aphid, the feeding behavior of tea aphids on six different tea cultivars was monitored by (EPG) technique. The result showed that the duration of El, E2 as well as (E I+E2) which was feeding waveforrns of Toxoptera aurantii (Boyer) in tea phloem was significantly different by variance analysis (P〈0.05) and so did the duration of the probing of T. aurantii in all the tea tissues. And the six tea cultivars were classified into three groups with cluster analysis, based on the six major parameters which were durations of np, C, El, E2, F, and G waveforms, then the six major parameters of these three groups were detected by variance analysis, and the rank of six different tea cultivars' resistance to T. aurantii from strong to weak was Zhongcha 108, Sucha 1, Anjibaicha, Longjing 43, Xicha 5, and Sucha 120. As this result was in accord with the investigation into the tea field, we concluded that EPG technique was one of the most important means to examine tea plant resistance to T. aurantii and the durations of waveform El, E2 and (El+E2) were important parameters for evaluating resistance of tea plants to tea aphids.
基金supported by the NSFC (Grant No. 31670262)Key Project of Applied Basic Research Program of Yunnan (Grant No. 2014FA040)+2 种基金100-Oversea-Top-Talents Recruitment plan of Yunnan to jinsong WuProject of Applied Basic Research Program of Yunnan(Grant No. 2017FB048) to Lan Mafounding (Grant No. 110201603008) to Dunhuang Fang
文摘Pleiotropic drug resistance(PDR) transporters are widely distributed membrane proteins catalyzing the export or import of a diverse array of molecules, and are involved in many plant responses to biotic and abiotic stresses. However, it is unclear whether PDRs are involved in Nicotiana attenuata resistance to the necrotic fungal pathogen Alternaria alternata. In this study, transcriptional levels of both NaPDR1 and NaPDR1-like were highly induced in N. attenuata leaves after A. alternata inoculation. Interestingly,silencing NaPDR1 or NaPDR1-like individually had little effect on N. attenuata resistance to A. alternata;however, when both genes were co-silenced plants became highly susceptible to the fungus, which was associated with elevated JA and ethylene responses. Neither NaPDR1 nor NaPDR1-like was significantly elicited by exogenous treatment with methyl jasmonate(MeJA), whereas both were highly induced by ethylene. The elicitation levels of both genes by A. alternata were significantly reduced in plants with impaired JA or ethylene signaling pathways. Thus, we conclude that both NaPDR1 and NaPDR1-like function redundantly to confer resistance against A. alternata in N. attenuata, and the elicitation of the transcripts of both genes by the fungus is partially dependent on ethylene and jasmonate signaling.
基金supported by grants from the Agricultural Science and Technology Innovation Program (ASTIP-TRIC01)National Natural Science Foundation of China (31571738)
文摘Cigar line Beinhart 1000-1 has effective durable resistance to black shank(BS) and is considered one of the most resistant sources in tobacco(Nicotiana tabacum L.). To investigate the inheritance and identification of stable quantitative trait loci(QTL) for BS response, F2,BC1 F2 individuals and BC1 F2:3 lines were produced from a cross between Beinhart 1000-1 and Xiaohuangjin 1025. Two major quantitative trait loci(M-QTL) named qBS7 and qBS17 were repeatedly detected under different conditions. QTL qBS7 was mapped to the region between PT30174 and PT60621 and explained 17.40%–25.60% of the phenotypic variance under different conditions. The other QTL qBS17 in interval PT61564–PT61538 of linkage group 17 was detected in a BC1 F2 population in the field and in BC1 F2:3 in both the field and at the seedling stage, explaining 6.90% to 11.60% of the phenotypic variance. The results improve our understanding of the inheritance of resistance to BS and provide information that can be used in marker-assisted breeding.
基金the National Natural Science Foundation of China for financial support(31530062 and 32025031)。
文摘Plant viruses are a group of intracellular pathogens that persistently threaten global food security.Significant advances in plant virology have been achieved by Chinese scientists over the last 20 years,including basic research and technologies for preventing and controlling plant viral diseases.Here,we review these milestones and advances,including the identification of new crop-infecting viruses,dissection of pathogenic mechanisms of multiple viruses,examination of multilayered interactions among viruses,their host plants,and virus-transmitting arthropod vectors,and in-depth interrogation of plantencoded resistance and susceptibility determinants.Notably,various plant virus-based vectors have also been successfully developed for gene function studies and target gene expression in plants.We also recommend future plant virology studies in China.
基金supported by the National Key R&D Program of China(2022YFD1401500 and 2022YFD1402100)the Nature Science Foundation of China(32202257,32272557,and 32072500)+5 种基金the Natural Science Foundation of Shandong Province(ZR2020MC117)the China Postdoctoral Science Foundation(2021M702027)the Major Basic Research Project of Natural Science Foundation of Shandong Province(ZR2022ZD23)the Taishan Scholar Program of Shandong Province(TSTP20221117)the Shandong Modern Agricultural Industry Technology System(SDAIT-04-08)and the Key Technology Research and Development Program of Shandong(2019JZZY020608).
文摘The plant apoplast,which serves as the frontline battleground for long-term host–pathogen interactions,harbors a wealth of disease resistance resources.However,the identification of the disease resistance proteins in the apoplast is relatively lacking.In this study,we identified and characterized the rice secretory protein OsSSP1(Oryza sativa secretory small protein 1).OsSSP1 can be secreted into the plant apoplast,and either in vitro treatment of recombinant OsSSP1 or overexpression of OsSSP1 in rice could trigger plant immune response.The expression of OsSSP1 is suppressed significantly during Magnaporthe oryzae infection in the susceptible rice variety Taibei 309,and OsSSP1-overexpressing lines all show strong resistance to M.oryzae.Combining the knockout and overexpression results,we found that OsSSP1 positively regulates plant immunity in response to fungal infection.Moreover,the recognition and immune response triggered by OsSSP1 depend on an uncharacterized transmembrane OsSSR1(secretory small protein receptor 1)and the key co-receptor OsBAK1,since most of the induced immune response and resistance are lost in the absence of OsSSR1 or OsBAK1.Intriguingly,the OsSSP1 protein is relatively stable and can still induce plant resistance after 1 week of storage in the open environment,and exogenous OsSSP1 treatment for a 2-week period did not affect rice yield.Collectively,our study reveals that OsSSP1 can be secreted into the apoplast and percepted by OsSSR1 and OsBAK1 during fungal infection,thereby triggering the immune response to enhance plant resistance to M.oryzae.These findings provide novel resources and potential strategies for crop breeding and disease control.
基金supported by the National Science Foundation(NSF)(MCB-1906060)National Institutes of Health(NIH)(R35GM149197)to P.H.,the NIH(R35GM144275)+1 种基金NSF(IOS-2049642)to L.S.the Youth Innovation Technology Project of Higher School in Shandong Province(2020KJF013)to S.H.
文摘The regulation of stomatal aperture opening and closure represents an evolutionary battle between plants and pathogens,characterized by adaptive strategies that influence both plant resistance and pathogen virulence.The ongoing climate change introduces further complexity,affecting pathogen invasion and host immunity.This review delves into recent advances on our understanding of the mechanisms governing immunity-related stomatal movement and patterning with an emphasis on the regulation of stomatal opening and closure dynamics by pathogen patterns and host phytocytokines.In addition,the review explores how climate changes impact plant–pathogen interactions by modulating stomatal behavior.In light of the pressing challenges associated with food security and the unpredictable nature of climate changes,future research in this field,which includes the investigation of spatiotemporal regulation and engineering of stomatal immunity,emerges as a promising avenue for enhancing crop resilience and contributing to climate control strategies.
基金financially supported by the National Natural Science Foundation of China (31371951)the National Key Technology R&D Program for Grain Crops, Ministry of Science and Technology of China (2016YFD0300701)the Science and Technology Innovation Project of Hunan Academy of Agricultural Sciences, China (2017JC41)
文摘Rice is one of the most important staple foods for the world population,but it is attacked by a number of destructive pests.While evidence from greenhouse and laboratory tests has shown that silicon(Si)amendment can confer enhanced resistance to pests in rice,few studies have directly demonstrated the Si-mediated protection from pests in a field situation.In this study,field plots with silicon amendments at 0,75,150 and 300 kg SiO2 ha-1 in early-and late-season rice were employed to evaluate the effects of silicon amendment on the occurrence of major insect pests and diseases and rice yield.Compared with the control plots without silicon amendment,plant damage by stem borer and leaf folder and population size of planthopper were significantly lower in three to five of the seven monitoring observations in each season in the plots amended with 300 kg SiO2 ha-1.The disease index of rice blast in the early-season rice was lower in the plots amended with Si at 300 kg SiO2 ha-1 than in the control plots,while Si protection from rice blast in the late-season rice and from rice sheath blight in the early-season rice were not apparent.An insignificant increase of rice yield by 16.4%(604 kg ha-1)was observed in the plots amended with 300 kg SiO2 ha-1 over the control plots.Our results indicate that Si amendment at 300kg SiO2 ha-1 can provide substantial protection from some of the rice pests under field conditions.These findings support the recommendation of silicon amendment as a key component of integrated management of rice pests.
基金This research was supported in part by National 973 Program(001CB109004)National 863 Program(2002AA212161)+1 种基金National Natural Science Foundation of China(39970489)Mon-santo LLC.
文摘In this study, a transgenic Bt maize hybrid (event MON 810 from Monsanto Company) expressing Cry1Ab protein derived from Bacillus thuringiensis (Bt) and its negative isoline hybrid were evaluated for control of the Asian corn borer, Ostrinia furnacalis (Guenée) (Lepidoptera: Pyralidae), in a field trial. Maize plants were artificially infested with neonate larvae of Asian corn borer at the mid-whorl (first-generation), pre-tassel (first- and/or second-generation), and silk (second-generation) growth stages. The transgenic Bt maize hybrid sustained significantly less leaf feeding damage (rating 1.0±0.0) than its negative isoline control (rating 7.3±0.1). With the Bt maize, 1.36.8% of plants were damaged by corn borer tunneling with <0.5 cm tunneling per stalk under different levels of infestation, compared with 100% of plants damaged with 9.325.0 cm tunneling per stalk for the negative isoline control. On average, transgenic Bt maize hybrids had only 0.010.05 tunnels per stalk and no stems were broken. In contrast, the negative isoline control had 3.118.36 tunnels per stalk and 31.273.9% of stems broken. Yields were significantly higher in transgenic Bt maize than in the control. These results demonstrate that transgenic Bt maize can significantly minimize yield losses caused by the Asian corn borer through resistance to the first- and second-generation larvae.
文摘In this research, supercritical carbon dioxide extraction (SFE) showed better extraction etlect when compared with Solid- liquid extraction (SLE), Soxhlet extraction (SEt and Ultrasonic extraction (UE), not only in the rate but also the time. The comparison among these three extraction modifiers, including acetone, ethanol and methanol demonstrated that ethanol was preferred to SFE due to its high extraction effect and low toxicology. In addition, parameter of SFE, influence of temperature and pressure were investigated, and the best extraction effect was achieved at the optima conditions, temperature of 40℃ and the pressure of 35 MPa. Thus, SFE is a highly effective method for flavonols extraction, requiring minimum energy and producing non-toxic byproduct. SFE-GC system is applied for the evaluation on flavonols that plays a key role in plant resistance to heavy metal, with its content and synthetase gene expression significantly increasing in plant when threatened by heavy metal. Besides, results indicated that flavonols can improve plant resistance to oxidative stress by quenching the redundant ROS in matrix.
文摘The aim of this study was to determine the allelopathic effects of <i><span style="font-family:Verdana;">Azadirachta indica</span></i><span style="font-family:Verdana;"> oil and aqueous extracts of </span><i><span style="font-family:Verdana;">Tithonia diversifolia</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Thevetia peruviana</span></i><span style="font-family:Verdana;"> on the growth and stimulation of metabolites involved in tomato plant resistance. Randomized in blocks within a shaded area, the different treatments prepared at 10% and 15% (v/v and w/v) in water were subsequently applied on tomatoes seeds to monitor the effect on germination, and on tomatoes leaves to monitor the effect on growth and resilience of the plants. The result showed that in stressful conditions all the treatment</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> significantly inhibit (p < 0.05) the germination capacity of the seeds from 21.22% to 92.61%, the germination rate from 39.82% to 92.76% and the germination viability of the seedlings from 64.67% to 100%. However, the negative allelopathic effect of the treatment was significantly reduced (p < 0.05) when used for germination initiation by botanical priming. In addition, while </span><i><span style="font-family:Verdana;">T. diversifolia</span></i><span style="font-family:Verdana;"> at 10% promotes a better aerial and root growth in tomato plants, </span><i><span style="font-family:Verdana;">T. peruviana</span></i><span style="font-family:Verdana;"> at 15% induces the activation of resistance mechanisms in tomato plants by increasing protein levels to 104.5%, phenol levels to 183.33% and peroxidase enzyme activity to 586.15%. Therefore, allelopathic compound of wild plants would be a good alternative for growth promotion and resistance of tomato crops.</span></span></span></span>
文摘Cotton (Gossypium hirsutum L.) has epidermal glands containing terpenoid aldehyde (TA) compounds that protect the plant from pests and diseases. One TA, gossypol, has two forms (+) and (-) that are present in varying amounts. This study evaluated the variation in roots for TA compounds and how environment affected the levels of these compounds. Similar to seed, gossypol was the predominant TA in roots. No heliocides were detected with only trace amounts of other TAs, such as hemigossypolone or hemigossypol, detected in a few lines. Among the glanded lines, there were significant differences in gossypol content. Percent plus gossypol was consistently 4% - 10% higher in roots than seed. One line, “Mac7”, had 12 - 14 ug/mg gossypol in roots and 18 ug/mg in seed as well as >90% (+) gossypol in both roots and seed. Unlike other tissues in glandless cotton, the roots of glandless lines consistently produced detectable amounts of gossypol with 77% to 82% in the (+) form. Multi-year field tests showed that although gossypol levels in the roots were more affected by insect pressure or other environmental conditions than seed, there was selectable variation in upland cotton for root gossypol content. Unlike other parts of a glandless plant, the roots retained a functioning biochemical pathway for gossypol production.