[ Objective ] The paper was to establish the near isogenic lines of Huangzaosi maize with resistance against maize head smut, and to provide basis for its wide application in breeding and production. [Method] Combing ...[ Objective ] The paper was to establish the near isogenic lines of Huangzaosi maize with resistance against maize head smut, and to provide basis for its wide application in breeding and production. [Method] Combing with hybrid, backcress and self-cross method, as well as molecular markers, Huangzaosi maize was successfully introduced with head smut resistance, and its near isogenic lines were studied. The characteristics of resistant and susceptible variation and the changes of combining ability of near isogenic lines after backcrossing breeding were observed. [ Result ] The incidence rate of Huangzansi maize in control was 46% ; the incidence rates of the selected 24 near isogenic lines of resistant Huangzaosi were all lower than 10%, and the selected rate was 92.6% ; the combining ability of most near isogenic lines of resistant Huangzaosi maize had no significant difference with that of H^i maize in control; the yields of hybrids prepared by several inbred lines such as M135 and M140 were outstanding, which exceeded the control Zhengdan 958, showing a higher combining ability. [ Conclusion] The phenotype and combining ability of near isngenic lines of Huangzaosi maize with resistance against maize head smut obtained in the test were very close to Huan- gzaosi, and its resistance against maize head smut was greatly increased, thus solving the problems of Huangzaesi without resistance against maize head smut.展开更多
In order to test the control effect of 6% tebuconazole FS on maize head smut and to select its optimal dose for mixing seed, field tests were performed in 2012 and 2013. The results showed that 6% tebuconazole FS was ...In order to test the control effect of 6% tebuconazole FS on maize head smut and to select its optimal dose for mixing seed, field tests were performed in 2012 and 2013. The results showed that 6% tebuconazole FS was effective to control maize head smut, and the control effect ranged from 73.4% to 91.1%. In addition, it also improved the maize yield by 36.7%-44.1%, compared with the blank control. The optimal dose of 6% tebuconazole FS for seed dressing was 166.5 g/100 kg to control head smut on maize.展开更多
Maize head smut is a worldwide disease, widely occurred in most maize fields. The disease had occurred in large area in the late 1970s, and became a limiting factor restricting the improvement of maize yield and total...Maize head smut is a worldwide disease, widely occurred in most maize fields. The disease had occurred in large area in the late 1970s, and became a limiting factor restricting the improvement of maize yield and total yield in China. After efforts of several generations of agricultural scientific workers, the symp- toms, pathogen, infection pathway, infection conditions, infection regularity and resistance genetic law of maize head smut have been studied. This paper introduces the incidence symptoms, pathogen sources, infection pathway, infection conditions, and physiological races of maize head smut, and put forwards the corresponding prevention measures, such as crop rotation, selection of resistant varieties, seed dressing, soil treatment with fungicides, promoting seedling emergence and strengthening field management.展开更多
This study was conducted to identify resistance sources against the newly documented pathotypes (P5 and P6) of </span><i><span style="font-family:Verdana;">Sporisorium</span></i>...This study was conducted to identify resistance sources against the newly documented pathotypes (P5 and P6) of </span><i><span style="font-family:Verdana;">Sporisorium</span></i> <i><span style="font-family:Verdana;">reilianum</span></i><span style="font-family:Verdana;">, causing sorghum head smut. A subset of 67 sorghum association panel (SAP) accessions, 29 in 2017 and 38 in 2018 along with checks BTx635 (resistant) and BTx643 (susceptible) were screened in the greenhouse against P5 and P6 pathotypes in two separate experiments in both years. At 18 to 20 days after planting, accessions were inoculated by injecting the seedlings below the apical meristem with sporidial suspensions following an established inoculation procedure. Three accessions (PI656091, PI533919, and PI533821) in 2017 </span><span style="font-family:Verdana;">and 17 accessions (PI597961, PI656071, PI656048, PI576435, PI534075, PI534145,</span><span style="font-family:Verdana;"> PI656057, PI576437, PI651492, PI656014, PI656025, PI655999, PI656010, PI656082, PI534123, PI533927, PI656100) in 2018 were identified as potential resistant sources to both P5 and P6 pathotypes of </span><i><span style="font-family:Verdana;">S.</span></i> <i><span style="font-family:Verdana;">reilianum</span></i><span style="font-family:Verdana;">. These SAP accessions are new sources that can be further used to develop new breeding parental lines and hybrids and mapping populations for quantitative trait loci markers closely linked to head smut resistance.展开更多
Head smut, caused by the fungal pathogen Sporisorium reilianum, poses a grave threat to maize(Zea mays) production worldwide. Here we report cytological and molecular evidence for maize resistance to head smut. During...Head smut, caused by the fungal pathogen Sporisorium reilianum, poses a grave threat to maize(Zea mays) production worldwide. Here we report cytological and molecular evidence for maize resistance to head smut. During early stages of root infection, S. reilianum mycelium was capable of penetrating the root epidermis of both resistant(Ji1037) and susceptible(HZ4) inbred lines. S. reilianum hyphae were observed in the root–stem junction at 6 days after inoculation. In an attempt to monitor hyphal spread within the maize plant,a highly specific and sensitive real-time PCR method was established to estimate the hyphal content in infected maize tissues. During the upward growth of endophytic S.reilianum, the extent of hyphal spread was markedly different between Ji1037 and HZ4. Very little or no pathogen was detected in aerial parts of Ji1037, whereas large amounts of pathogen accumulated in aboveground tissues, particularly inflorescences, of HZ4. Thus,maize resistance to S. reilianum was achieved mainly by inhibition of endophytic hyphal growth rather than by prevention of early-root penetration by the pathogen.展开更多
Obligate biotrophs depend on living hosts for nutrient acquisition to complete their life cycle,yet the mechanisms by which hosts restrict nutrient availability to pathogens remain largely unknown.The fungal pathogen ...Obligate biotrophs depend on living hosts for nutrient acquisition to complete their life cycle,yet the mechanisms by which hosts restrict nutrient availability to pathogens remain largely unknown.The fungal pathogen Sporisorium reilianum infects maize seedlings and causes head smut disease in inflorescences at maturity,while a cell wall-associated kinase,ZmWAK,provides quantitative resistance against it.In this study,we demonstrate that S.reilianum can rapidly activate ZmWAK kinase activity,which is sustained by the 407th threonine residue in the juxtamembrane domain,enabling it to interact with and phosphorylate ZmSnRK1a2,a conserved sucrose non-fermenting-related kinase a subunit.The activated ZmSnRK1a2 translocates from the cytoplasm to the nucleus,where it phosphorylates and destabilizes the transcription factor ZmWRKY53.The reduced ZmWRKY53 abundance leads to the downregulation of genes involved in transmembrane transport and carbohydrate metabolism,resulting in nutrient starvation for S.reilianum in the apoplast.Collectively,our study uncovers a WAK-SnRK1a2-WRKY53 signaling module in maize that conveys phosphorylation cascades from the plasma membrane to the nucleus to confer plant resistance against head smut in maize,offering new insights and potential targets for crop disease management.展开更多
文摘[ Objective ] The paper was to establish the near isogenic lines of Huangzaosi maize with resistance against maize head smut, and to provide basis for its wide application in breeding and production. [Method] Combing with hybrid, backcress and self-cross method, as well as molecular markers, Huangzaosi maize was successfully introduced with head smut resistance, and its near isogenic lines were studied. The characteristics of resistant and susceptible variation and the changes of combining ability of near isogenic lines after backcrossing breeding were observed. [ Result ] The incidence rate of Huangzansi maize in control was 46% ; the incidence rates of the selected 24 near isogenic lines of resistant Huangzaosi were all lower than 10%, and the selected rate was 92.6% ; the combining ability of most near isogenic lines of resistant Huangzaosi maize had no significant difference with that of H^i maize in control; the yields of hybrids prepared by several inbred lines such as M135 and M140 were outstanding, which exceeded the control Zhengdan 958, showing a higher combining ability. [ Conclusion] The phenotype and combining ability of near isngenic lines of Huangzaosi maize with resistance against maize head smut obtained in the test were very close to Huan- gzaosi, and its resistance against maize head smut was greatly increased, thus solving the problems of Huangzaesi without resistance against maize head smut.
文摘In order to test the control effect of 6% tebuconazole FS on maize head smut and to select its optimal dose for mixing seed, field tests were performed in 2012 and 2013. The results showed that 6% tebuconazole FS was effective to control maize head smut, and the control effect ranged from 73.4% to 91.1%. In addition, it also improved the maize yield by 36.7%-44.1%, compared with the blank control. The optimal dose of 6% tebuconazole FS for seed dressing was 166.5 g/100 kg to control head smut on maize.
文摘Maize head smut is a worldwide disease, widely occurred in most maize fields. The disease had occurred in large area in the late 1970s, and became a limiting factor restricting the improvement of maize yield and total yield in China. After efforts of several generations of agricultural scientific workers, the symp- toms, pathogen, infection pathway, infection conditions, infection regularity and resistance genetic law of maize head smut have been studied. This paper introduces the incidence symptoms, pathogen sources, infection pathway, infection conditions, and physiological races of maize head smut, and put forwards the corresponding prevention measures, such as crop rotation, selection of resistant varieties, seed dressing, soil treatment with fungicides, promoting seedling emergence and strengthening field management.
文摘This study was conducted to identify resistance sources against the newly documented pathotypes (P5 and P6) of </span><i><span style="font-family:Verdana;">Sporisorium</span></i> <i><span style="font-family:Verdana;">reilianum</span></i><span style="font-family:Verdana;">, causing sorghum head smut. A subset of 67 sorghum association panel (SAP) accessions, 29 in 2017 and 38 in 2018 along with checks BTx635 (resistant) and BTx643 (susceptible) were screened in the greenhouse against P5 and P6 pathotypes in two separate experiments in both years. At 18 to 20 days after planting, accessions were inoculated by injecting the seedlings below the apical meristem with sporidial suspensions following an established inoculation procedure. Three accessions (PI656091, PI533919, and PI533821) in 2017 </span><span style="font-family:Verdana;">and 17 accessions (PI597961, PI656071, PI656048, PI576435, PI534075, PI534145,</span><span style="font-family:Verdana;"> PI656057, PI576437, PI651492, PI656014, PI656025, PI655999, PI656010, PI656082, PI534123, PI533927, PI656100) in 2018 were identified as potential resistant sources to both P5 and P6 pathotypes of </span><i><span style="font-family:Verdana;">S.</span></i> <i><span style="font-family:Verdana;">reilianum</span></i><span style="font-family:Verdana;">. These SAP accessions are new sources that can be further used to develop new breeding parental lines and hybrids and mapping populations for quantitative trait loci markers closely linked to head smut resistance.
基金funded by the Ministry of Agriculture of China (2013ZX08009003-001-007)the National High Technology Research and Development Program of China (2012AA101104, 2012AA10A306)
文摘Head smut, caused by the fungal pathogen Sporisorium reilianum, poses a grave threat to maize(Zea mays) production worldwide. Here we report cytological and molecular evidence for maize resistance to head smut. During early stages of root infection, S. reilianum mycelium was capable of penetrating the root epidermis of both resistant(Ji1037) and susceptible(HZ4) inbred lines. S. reilianum hyphae were observed in the root–stem junction at 6 days after inoculation. In an attempt to monitor hyphal spread within the maize plant,a highly specific and sensitive real-time PCR method was established to estimate the hyphal content in infected maize tissues. During the upward growth of endophytic S.reilianum, the extent of hyphal spread was markedly different between Ji1037 and HZ4. Very little or no pathogen was detected in aerial parts of Ji1037, whereas large amounts of pathogen accumulated in aboveground tissues, particularly inflorescences, of HZ4. Thus,maize resistance to S. reilianum was achieved mainly by inhibition of endophytic hyphal growth rather than by prevention of early-root penetration by the pathogen.
文摘Obligate biotrophs depend on living hosts for nutrient acquisition to complete their life cycle,yet the mechanisms by which hosts restrict nutrient availability to pathogens remain largely unknown.The fungal pathogen Sporisorium reilianum infects maize seedlings and causes head smut disease in inflorescences at maturity,while a cell wall-associated kinase,ZmWAK,provides quantitative resistance against it.In this study,we demonstrate that S.reilianum can rapidly activate ZmWAK kinase activity,which is sustained by the 407th threonine residue in the juxtamembrane domain,enabling it to interact with and phosphorylate ZmSnRK1a2,a conserved sucrose non-fermenting-related kinase a subunit.The activated ZmSnRK1a2 translocates from the cytoplasm to the nucleus,where it phosphorylates and destabilizes the transcription factor ZmWRKY53.The reduced ZmWRKY53 abundance leads to the downregulation of genes involved in transmembrane transport and carbohydrate metabolism,resulting in nutrient starvation for S.reilianum in the apoplast.Collectively,our study uncovers a WAK-SnRK1a2-WRKY53 signaling module in maize that conveys phosphorylation cascades from the plasma membrane to the nucleus to confer plant resistance against head smut in maize,offering new insights and potential targets for crop disease management.
