The potato rot nematode(Ditylenchus destructor) is a very economically important nematode in agronomic and horticultural plants worldwide. In this study, 43 populations of D. destructor were collected from different h...The potato rot nematode(Ditylenchus destructor) is a very economically important nematode in agronomic and horticultural plants worldwide. In this study, 43 populations of D. destructor were collected from different hosts across China, including 37 populations from Chinese herbal medicine plants. Obtained sequences of ITS-rDNA and D2–D3of 28S-rDNA genes of D. destructor were compared and analyzed. Nine types of significant length variations in ITS sequences were observed among all populations. The differences in ITS1 length were mainly caused by the presence of repetitive elements with substantial base substitutions. Reconstructions of ITS1 secondary structures showed that the minisatellites formed a stem structure. Ten haplotypes were observed in all populations based on mutations and variations of helix H9. Among them, 3 known haplotypes(A–C) were found in 7 populations isolated from potato,sweet potato, and Codonopsis pilosula, and 7 unique haplotypes were found in other 36 populations collected from C. pilosula and Angelica sinensis compared with 7 haplotypes(A–G) according to Subbotin' system. These unique haplotypes were different from haplotypes A–G, and we named them as haplotypes H–N. The present results showed that a total of 14 haplotypes(A–N) of ITS-rDNA have been found in D. destructor. Phylogenetic analyses of ITSrDNA and D2–D3 showed that all populations of D. destructor were clustered into two major clades: one clade only containing haplotype A from sweet potato and the other containing haplotypes B–N from other plants. For further verification, PCR-ITS-RFLP profiles were conducted on 7 new haplotypes. Collectively, our study suggests that D. destructor populations on Chinese medicinal materials are very different from those on other hosts and this work provides a paradigm for relevant researches.展开更多
Potato rot nematode Ditylenchus destructor is one of the most damaging pests in potato-producing regions and causes severe yield losses worldwide.However,D.destructor has been rarely reported in potato crops in China....Potato rot nematode Ditylenchus destructor is one of the most damaging pests in potato-producing regions and causes severe yield losses worldwide.However,D.destructor has been rarely reported in potato crops in China.We collected 542 samples from 17 Chinese provinces during 2016-2020 for the detection of D.destructor using species-specific primers and universal primers targeting ribosomal internal transcribed spacer(ITS)or 28S ribosomal RNA(rRNA)sequences.D.destructor was detected in 14.94%of total samples,primarily in Inner Mongolia Autonomous Region(43 sites),Jilin Province(12 sites),and Shaanxi Province(9 sites).The nematode was for the first time detected in Guizhou Province and Ningxia Hui Autonomous Region.Phylogenetic analysis of 33 ITS sequences along with the prediction of the secondary structure of the helix H9 of ITS1 sequences revealed that haplotypes A,B,and C accounted for 6.06%,9.09%,and 69.70%of our detections,respectively,while 15.15%were comprised of haplotypes H-L,and extensive genetic diversity of ITS sequences was detected in samples from Gansu Province.Using RNAfold software,we analyzed the haplotypes of 124 Chinese D.destructor populations based on their ITS sequences,and the results showed that haplotypes A,B,C,E,F,and new haplotypes M-P accounted for 49.19%,12.10%,15.32%,3.23%,1.61%,and 18.55%of the total sequences,respectively.Infection tests on the potato cultivar‘Helan 15’showed significant difference in infection capacity among different D.destructor populations.The information obtained in this study on spatial patterns of D.destructor haplotypes in China provides valuable insights into the development of an integrated approach for the management of this plant-parasitic nematode.展开更多
基金supported by the National Natural Science Foundation of China (31760507)the National Key R&D Program of China (2018YFC1706301)。
文摘The potato rot nematode(Ditylenchus destructor) is a very economically important nematode in agronomic and horticultural plants worldwide. In this study, 43 populations of D. destructor were collected from different hosts across China, including 37 populations from Chinese herbal medicine plants. Obtained sequences of ITS-rDNA and D2–D3of 28S-rDNA genes of D. destructor were compared and analyzed. Nine types of significant length variations in ITS sequences were observed among all populations. The differences in ITS1 length were mainly caused by the presence of repetitive elements with substantial base substitutions. Reconstructions of ITS1 secondary structures showed that the minisatellites formed a stem structure. Ten haplotypes were observed in all populations based on mutations and variations of helix H9. Among them, 3 known haplotypes(A–C) were found in 7 populations isolated from potato,sweet potato, and Codonopsis pilosula, and 7 unique haplotypes were found in other 36 populations collected from C. pilosula and Angelica sinensis compared with 7 haplotypes(A–G) according to Subbotin' system. These unique haplotypes were different from haplotypes A–G, and we named them as haplotypes H–N. The present results showed that a total of 14 haplotypes(A–N) of ITS-rDNA have been found in D. destructor. Phylogenetic analyses of ITSrDNA and D2–D3 showed that all populations of D. destructor were clustered into two major clades: one clade only containing haplotype A from sweet potato and the other containing haplotypes B–N from other plants. For further verification, PCR-ITS-RFLP profiles were conducted on 7 new haplotypes. Collectively, our study suggests that D. destructor populations on Chinese medicinal materials are very different from those on other hosts and this work provides a paradigm for relevant researches.
基金supported by the National Natural Science Foundation of China(32072398)the Key Project of Shaanxi Academy of Sciences(2020K-04)the Agricultural Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences,China(ASTIP-02-IPP-04).
文摘Potato rot nematode Ditylenchus destructor is one of the most damaging pests in potato-producing regions and causes severe yield losses worldwide.However,D.destructor has been rarely reported in potato crops in China.We collected 542 samples from 17 Chinese provinces during 2016-2020 for the detection of D.destructor using species-specific primers and universal primers targeting ribosomal internal transcribed spacer(ITS)or 28S ribosomal RNA(rRNA)sequences.D.destructor was detected in 14.94%of total samples,primarily in Inner Mongolia Autonomous Region(43 sites),Jilin Province(12 sites),and Shaanxi Province(9 sites).The nematode was for the first time detected in Guizhou Province and Ningxia Hui Autonomous Region.Phylogenetic analysis of 33 ITS sequences along with the prediction of the secondary structure of the helix H9 of ITS1 sequences revealed that haplotypes A,B,and C accounted for 6.06%,9.09%,and 69.70%of our detections,respectively,while 15.15%were comprised of haplotypes H-L,and extensive genetic diversity of ITS sequences was detected in samples from Gansu Province.Using RNAfold software,we analyzed the haplotypes of 124 Chinese D.destructor populations based on their ITS sequences,and the results showed that haplotypes A,B,C,E,F,and new haplotypes M-P accounted for 49.19%,12.10%,15.32%,3.23%,1.61%,and 18.55%of the total sequences,respectively.Infection tests on the potato cultivar‘Helan 15’showed significant difference in infection capacity among different D.destructor populations.The information obtained in this study on spatial patterns of D.destructor haplotypes in China provides valuable insights into the development of an integrated approach for the management of this plant-parasitic nematode.
