• Title/Summary/Keyword: agricultural pests

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A Duplex PCR Assay for Rapid Detection of Phytophthora nicotianae and Thielaviopsis basicola

  • Liu, Na;Jiang, Shijun;Feng, Songli;Shang, Wenyan;Xing, Guozhen;Qiu, Rui;Li, Chengjun;Li, Shujun;Zheng, Wenming
    • The Plant Pathology Journal
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    • v.35 no.2
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    • pp.172-177
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    • 2019
  • A duplex PCR method was developed for simultaneous detection and identification of tobacco root rot pathogens Phytophthora nicotianae and Thielaviopsis basicola. The specific primers for P. nicotianae were developed based on its internal transcribed spacer (ITS) regions of ribosomal gene, ras gene and hgd gene, while the specific primers for T. basicola were designed based on its ITS regions and ${\beta}$-tubulin gene. The specificity of the primers was determined using isolates of P. nicotianae, T. basicola and control samples. The results showed that the target pathogens could be detected from diseased tobacco plants by a combination of the specific primers. The sensitivity limitation was $100fg/{\mu}l$ of pure genomic DNA of the pathogens. This new assay can be applied to screen out target pathogens rapidly and reliably in one PCR and will be an important tool for the identification and precise early prediction of these two destructive diseases of tobacco.

Identification of a pr 1-like Gene of Entomopathogenic Fungus, Beauveria bassiana F-101 Isolated from Thecodiplosis japonensis

  • Shin Sang Chul;Roh Jong Yul;Shim Hee Jin;Kim Soon Kee;Kim Chul Su;Park Il Kwon;Jeon Mun Jang;Je Yeon Ho
    • International Journal of Industrial Entomology and Biomaterials
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    • v.10 no.2
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    • pp.131-136
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    • 2005
  • Beauveria bassiana F-101, which has high toxicity toward Acantholyda parki as well as Thecodiplosis japonensis, was an isolate to develop an alternative control system against the major forest pests. Up to now, in B. bassiana, only one pr1 gene has been isolated and characterized. Therefore, we here reported the identification of a pr1-like gene, which would be a factor of toxicity from B. bassiana F-101. The oligonucleotides for the amplification of the pr1-like gene, were chosen based on the conserved regions of the subtilisin family enzymes, pr1 genes of B. bassiana and Metarhizium anisopliae, and proteinase K of Tritirachium album. The cloned PCR fragment had 1111 bp including 52 bp intron. The deduced Pr1-like peptide showed a low identity with Pr1s of entomopathogenic fungi such as B. bassiana Pr1 (BbPr1) and M. anisopliae Pr1 (MaPr1) as well as the proteinase K of T. album (TaPrK). Instead, the deduced peptide had a substantially high amino acid sequence identity $(>65\%)$ with the serine proteases of Magnaporthe grisea (MgSPM1) and Podospora anserina (PaPspA). These results, therefore, appear to suggest that the putative Pr1-like peptide of B. bassiana F-101 belongs to the subtilisin-like serine protease family and may be a novel gene.

Study of Major Insect Pests on Rice and Corn in Four Provinces in Red River Delta of Vietnam During 2018- 2022

  • Thuy Linh Pham;Ohseok Kwon
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • v.5 no.1
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    • pp.21-27
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    • 2024
  • Harmful pet insects, if not controlled, can negatively affect people, plants and their surrounding environment. In Vietnam, all crops are regularly impacted by pest insects. In serious cases, crops can be totally destroyed by insect pests. Harmful insects that damage crops often grow fast and increase rapidly. Therefore, research on insects is crucial for managing pests, protecting crops, and forecasting pest situation in the following years. This study aimed to collect data regarding changes of pests on rice and corn as two main crops in four provinces in Red River Delta of Vietnam, including Thai Binh, Nam Dinh, Ha Nam, and Hung Yen, from 2018 to 2022. Primary data were collected from reports of government agencies and official statistics. Based on these data, this study evaluated changes of pest insects in five years, discussed reasons for such changes and response methods, and forecasted pest's behavior in the following years. Significant findings of this study include the fact that Vietnam has to face many difficulties to develop its agricultural sector. For insect management, an essential action is to do ground surveys to gather all related data including weather data, pesticide data, crop yield, and product quality. This information is meaningful for finding out causes of changes, understanding relationships between insects and surrounding factors, and predicting the situation in the following years.

Expression and Synergistic Effect of Bacillus thuringiensis CrylAc in Lepidopteran Toxic Strain to Plutella xylostella

  • Kang, Joong-Nam;Roh, Jong-Yul;Shin, Sang-Chul;Ko, Sang-Hyun;Chung, Yeong-Jin;Kim, Yang-Su;Wang, Yong;Choi, Hee-Kyu;Li, Ming-Shun;Choi, Jae-Young;Je, Yeon-Ho
    • International Journal of Industrial Entomology and Biomaterials
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    • v.14 no.1
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    • pp.33-36
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    • 2007
  • To improve insecticidal activity of B. thuringiensis 2385-1 (Bt 2385-1), a recombinant plasmid, pHT1K-1Ac, was introduced into lepidopteran toxic Bt 2385-1 by electroporation. The presence of the recombinant plasmid in Bt 2385-1 after electroporation was confirmed by PCR. Bt 2385-1 transformant was named as Bt pHT1K-1Ac/2385-1 (1K-1Ac/2385-1). The 1K-1Ac/2385-1 transformant produced bipyramidal-shaped parasporal inclusion as like the wild-type strain, Bt 2385-1, and showed an 130 kDa band of Cry1Ac protein. The insecticidal activity of 1K-lAc/2385-1 against S. exigua was similar to that of Bt 2385-1 but the $LC_{50}$ value of transformant against P. xylostella was 1.8 times lower. Through these bioassay results, it was confirmed that toxicity of Bt 2385-1 transformant showed synergistic effect by introducing Cry1Ac. These results suggested that the multiple expressions of Cry proteins in a promising Bt strain may interact synergistically in insect midgut, resulting in increase of toxicity and expansion of host spectrum.

Development and evaluation of a model for management of plant pests in organic cucumber cultivation

  • Ko, S.J.;Kang, B.R.;Kim, D.I.;Choi, D.S.;Kim, S.G.;Kim, H.K.;Kim, H.J.;Choi, K.J.;Kim, Y.C.
    • Korean Journal of Organic Agriculture
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    • v.19 no.spc
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    • pp.263-266
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    • 2011
  • Crop protection strategies in organic horticulture aim to prevent insect pest and plant disease problems through utilization of non-chemical based control means. In order to develop a model for management of plant diseases and insects in organic cucumber cultivation, we compared efficacies between chemical pesticide spraying system and biological control means in semi-forcing and retarding cucumber cultivation during 2005 and 2006. Conventional chemical spray program using various chemical pesticides was applied 5 - 10 days intervals, while two different non-chemical pesticide application programs using two formulated biopesticides Topseed$^{TM}$ and Q-fect$^{TM}$, Suncho$^{TM}$, and Sangsungje$^{TM}$ (biocontrol agents 1) and using egg-yolk and cooking oil(EYCO), Bordeaux mixture, Suncho$^{TM}$, and Sangsungje$^{TM}$ (biocontrol agents 2) were applied 5 - 7 days intervals during entire cucumber cultivation period. Efficacy of both biocontrol agents programs was effective to comparable to conventional chemical pesitice spray program to control plant diseases such as powdery mildew and downy mildew as well as insect pests such as aphids and thrips which are known as major threats in cucumber organic cultivation. In this study, we established and evaluated an effective and economic crop protection strategy using various biological resources can be used to control plant diseases and pests simultaneously in organic cucumber cultivation field.

Question Similarity Measurement of Chinese Crop Diseases and Insect Pests Based on Mixed Information Extraction

  • Zhou, Han;Guo, Xuchao;Liu, Chengqi;Tang, Zhan;Lu, Shuhan;Li, Lin
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.11
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    • pp.3991-4010
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    • 2021
  • The Question Similarity Measurement of Chinese Crop Diseases and Insect Pests (QSM-CCD&IP) aims to judge the user's tendency to ask questions regarding input problems. The measurement is the basis of the Agricultural Knowledge Question and Answering (Q & A) system, information retrieval, and other tasks. However, the corpus and measurement methods available in this field have some deficiencies. In addition, error propagation may occur when the word boundary features and local context information are ignored when the general method embeds sentences. Hence, these factors make the task challenging. To solve the above problems and tackle the Question Similarity Measurement task in this work, a corpus on Chinese crop diseases and insect pests(CCDIP), which contains 13 categories, was established. Then, taking the CCDIP as the research object, this study proposes a Chinese agricultural text similarity matching model, namely, the AgrCQS. This model is based on mixed information extraction. Specifically, the hybrid embedding layer can enrich character information and improve the recognition ability of the model on the word boundary. The multi-scale local information can be extracted by multi-core convolutional neural network based on multi-weight (MM-CNN). The self-attention mechanism can enhance the fusion ability of the model on global information. In this research, the performance of the AgrCQS on the CCDIP is verified, and three benchmark datasets, namely, AFQMC, LCQMC, and BQ, are used. The accuracy rates are 93.92%, 74.42%, 86.35%, and 83.05%, respectively, which are higher than that of baseline systems without using any external knowledge. Additionally, the proposed method module can be extracted separately and applied to other models, thus providing reference for related research.

Occurrence of Insect Pests in Rubus coreanus Miquel (복분자딸기에서 발생하는 해충 종류 및 발생 양상)

  • Lim, Ju-Rak;Choi, Seon-U;Kim, Ju-Hee;Lee, Ki-Kwon;Cheong, Seong-Soo;Ryu, Jeong;Hwang, Chang-Yeon
    • Korean journal of applied entomology
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    • v.49 no.2
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    • pp.97-103
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    • 2010
  • In this study, 5 species (Tetranychus kanzawai Kishida, Endoclyta excrescens (Butler), leaf roller caterpillar (Adoxophyes orana Fisher), Anomis mesogona (Walker), and Aulacaspis rosae (Bouche)) were found in Rubus coreanus Miquel in Jeonbuk province, from 2006 to 2008. T. kanzawai appeared in mid-May and showed three peaks in late June, mid-July, and late August. Its density was over 10 adults per leaf. A. mesogona appeared in mid-June and showed two peaks in late July, and early October. Of the 28 insect pests in pre-harvesting, the 7 main species were T. kanzawai, T. urticae, A. orana, Lygocoris lucorum Meyer, Frankliniella intonsa (Trybom), Psylliodes punctifrons Baly and Motschulskyia serrata (Matsumura). Of the 19 insect pests in after-harvesting, the 6 main species were T. kanzawai, E. excrescens, A. mesogona, A. orana, P. punctifrons and A. rosae. Growth of R. coreanus decreased when insect pests were not managed and yields decreased approx. 7% a year. Management of insect pests in field using pesticide was not different.

Comparison of Environmental-Friendly and Chemical Spray Calendar for Controlling Diseases and Insect Pests of Strawberry during Nursery Seasons (딸기 육묘기 병해충 관리를 위한 친환경과 화학적 방제력 비교)

  • Nam, Myeong Hyeon;Kim, Hyun Sook;Kim, Tae Il;Lee, Eun Mo
    • Research in Plant Disease
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    • v.21 no.4
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    • pp.273-279
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    • 2015
  • Major diseases and insect pests in nursery season of strawberry were anthracnose, powdery mildew, Fusarium wilt, two-spotted spider mite, and aphids. Environmental-friendly and chemical application schedules can improve diseases and insect pests control with relatively fewer organic and chemical materials inputs compared with spray programs when it's occurred. Field experiments were performed in 2012 to 2013 according to calendar-based spray programs with environmental-friendly spray calendar (EFSC) and conventional chemical spray calendar (CSC) for controlling diseases and insect pests of strawberry plants cv, Seolhyang during the two nursery seasons. EFSC did reduce the incidence of diseases and insect pests as compared to the non-treated control. Incidence of anthracnose and powdery mildew by EFSC and CSC was similar in 2012 and 2013 seasons. In addition, occurrence of two-spotted spider mite in EFSC in 2013 was similar to those of CSC and was shown highly in early and mid-June both 2012 and 2013 seasons. Occurrence of aphid in EFSC was shown highly in early and mid-June both 2012 and 2013 seasons. These results suggest that EFSC program may be effective for controlling strawberry diseases and insect pests by using environmental-friendly organic materials.

Pest Lists and Their Damages on Mango, Dragon Fruit and Atemoya in Jeju, Korea (제주도에서 재배되는 망고, 용과, 아떼모야의 주요 해충과 피해)

  • Choi, Kyung San;Yang, Jin Young;Park, Young Mi;Kim, Sora;Choi, Hwalran;Lyu, Dongpyo;Kim, Dong-Soon
    • Korean journal of applied entomology
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    • v.52 no.1
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    • pp.45-51
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    • 2013
  • Tropical plants of mango(Mangefera indica), dragon fruit(Hylocereus undatus), and atemoya(Annona cherimola ${\times}$ A. squamosa) are cultivated in Jeju, Korea. A pest survey on those tropical fruits was conducted from 2008 to 2011. Major pests of Mango were thrips, aphid, mealybug, and lepidoptera species. Thrips palmi and Scirtothrips dorsalis were the most important pests in mango fields. T. palmi mainly injured the leaf but S. dorsalis injured the leaf and fruit. Lepidoptera mango pests injured leaves but some larva of Adoxophyes honmai injured fruit surface around the stem. Aphid pests, Aphis gossypii and Myzus persicae, injured the shoots and Pseudococcus kraunhiae occurred on the stem and fruit. Ant species, A. gossypii, and S. litura, were important pests on dragon fruit. Ants and aphid occurred and injured the stem, flower, and fruit. Spodoptera litura larva severely injured the stem. Among the atemoya pests, S. litura and Homona magnanima caused severe damage.

Complete Mitochondrial Genome of Brown Marmorated Stink Bug Halyomorpha halys (Hemiptera: Pentatomidae), and Phylogenetic Relationships of Hemipteran Suborders

  • Lee, Wonhoon;Kang, Joongnam;Jung, Chansik;Hoelmer, Kim;Lee, Si Hyeock;Lee, Seunghwan
    • Molecules and Cells
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    • v.28 no.3
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    • pp.155-165
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    • 2009
  • The newly sequenced complete mitochondrial genome of the brown marmorated stink bug, Halyomorpha halys($St{\aa}l$) (Hemiptera: Pentatomidae), is a circular molecule of 16,518 bp with a total A+T content of 76.4% and two extensive repeat regions in A+T rich region. Nucleotide composition and codon usage of H. halys are about average when compared with values observed in 19 other published hemipteran mitochondrial genomes. Phylogenetic analyses using these 20 hemipteran mitochondrial genomes support the currently accepted hypothesis that suborders Heteroptera and Auchenorrhyncha form a monophyletic group. The mitochondrial gene arrangements of the 20 genomes are also consistent with our results.