1
|
Massé D, Candresse T, Filloux D, Massart S, Cassam N, Hostachy B, Marais A, Fernandez E, Roumagnac P, Verdin E, Teycheney PY, Lett JM, Lefeuvre P. Characterization of Six Ampeloviruses Infecting Pineapple in Reunion Island Using a Combination of High-Throughput Sequencing Approaches. Viruses 2024; 16:1146. [PMID: 39066307 PMCID: PMC11281624 DOI: 10.3390/v16071146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Revised: 07/09/2024] [Accepted: 07/09/2024] [Indexed: 07/28/2024] Open
Abstract
The cultivation of pineapple (Ananas comosus) is threatened worldwide by mealybug wilt disease of pineapple (MWP), whose etiology is not yet fully elucidated. In this study, we characterized pineapple mealybug wilt-associated ampeloviruses (PMWaVs, family Closteroviridae) from a diseased pineapple plant collected from Reunion Island, using a high-throughput sequencing approach combining Illumina short reads and Nanopore long reads. Reads co-assembly resulted in complete or near-complete genomes for six distinct ampeloviruses, including the first complete genome of pineapple mealybug wilt-associated virus 5 (PMWaV5) and that of a new species tentatively named pineapple mealybug wilt-associated virus 7 (PMWaV7). Short reads data provided high genome coverage and sequencing depths for all six viral genomes, contrary to long reads data. The 5' and 3' ends of the genome for most of the six ampeloviruses could be recovered from long reads, providing an alternative to RACE-PCRs. Phylogenetic analyses did not unveil any geographic structuring of the diversity of PMWaV1, PMWaV2 and PMWaV3 isolates, supporting the current hypothesis that PMWaVs were mainly spread by human activity and vegetative propagation.
Collapse
Affiliation(s)
- Delphine Massé
- ANSES—LSV RAPT, F-97410 St. Pierre, La Réunion, France; (N.C.); (B.H.)
- UMR PVBMT, Université de La Réunion, F-97410 St. Pierre, La Réunion, France
| | - Thierry Candresse
- INRAe, UMR 1332 Biologie du Fruit et Pathologie, Université Bordeaux, CS20032, F-33882 Villenave d’Ornon, France; (T.C.); (A.M.)
| | - Denis Filloux
- CIRAD, UMR PHIM, F-34090 Montpellier, France; (D.F.); (E.F.); (P.R.)
- PHIM Plant Health Institute, Université Montpellier, CIRAD, INRAE, Institut Agro, IRD, F-34090 Montpellier, France
| | - Sébastien Massart
- Plant Pathology Laboratory, Gembloux Agro-Bio Tech, University of Liège, 5030 Gembloux, Belgium;
| | - Nathalie Cassam
- ANSES—LSV RAPT, F-97410 St. Pierre, La Réunion, France; (N.C.); (B.H.)
| | - Bruno Hostachy
- ANSES—LSV RAPT, F-97410 St. Pierre, La Réunion, France; (N.C.); (B.H.)
| | - Armelle Marais
- INRAe, UMR 1332 Biologie du Fruit et Pathologie, Université Bordeaux, CS20032, F-33882 Villenave d’Ornon, France; (T.C.); (A.M.)
| | - Emmanuel Fernandez
- CIRAD, UMR PHIM, F-34090 Montpellier, France; (D.F.); (E.F.); (P.R.)
- PHIM Plant Health Institute, Université Montpellier, CIRAD, INRAE, Institut Agro, IRD, F-34090 Montpellier, France
| | - Philippe Roumagnac
- CIRAD, UMR PHIM, F-34090 Montpellier, France; (D.F.); (E.F.); (P.R.)
- PHIM Plant Health Institute, Université Montpellier, CIRAD, INRAE, Institut Agro, IRD, F-34090 Montpellier, France
| | - Eric Verdin
- INRAe, UR407 Unité de Pathologie Végétale, CS 60094, F-84140 Montfavet, France;
| | - Pierre-Yves Teycheney
- CIRAD, UMR PVBMT, F-97410 St. Pierre, La Réunion, France; (P.-Y.T.); (J.-M.L.); (P.L.)
| | - Jean-Michel Lett
- CIRAD, UMR PVBMT, F-97410 St. Pierre, La Réunion, France; (P.-Y.T.); (J.-M.L.); (P.L.)
| | - Pierre Lefeuvre
- CIRAD, UMR PVBMT, F-97410 St. Pierre, La Réunion, France; (P.-Y.T.); (J.-M.L.); (P.L.)
| |
Collapse
|
2
|
Genetic Diversity of Viral Populations Associated with Ananas Germplasm and Improvement of Virus Diagnostic Protocols. Pathogens 2022; 11:pathogens11121470. [PMID: 36558805 PMCID: PMC9787488 DOI: 10.3390/pathogens11121470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/24/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022] Open
Abstract
Pineapple (Ananas comosus L. [Merr.]) accessions from the U.S. Tropical Plant Genetic Resources and Disease Research (TPGRDR) in Hilo, Hawaii were subjected to RNA-sequencing to study the occurrence of viral populations associated with this vegetatively propagated crop. Analysis of high-throughput sequencing data obtained from 24 germplasm accessions and public domain transcriptome shotgun assembly (TSA) data identified two novel sadwaviruses, putatively named "pineapple secovirus C" (PSV-C) and "pineapple secovirus D" (PSV-D). They shared low amino acid sequence identity (from 34.8 to 41.3%) compared with their homologs in the Pro-pol region of the previously reported PSV-A and PSV-B. The complete genome (7485 bp) corresponding to a previously reported partial sequence of the badnavirus, pineapple bacilliform ER virus (PBERV), was retrieved from one of the datasets. Overall, we discovered a total of 69 viral sequences representing ten members within the Ampelovirus, Sadwavirus, and Badnavirus genera. Genetic diversity and recombination events were found in members of the pineapple mealybug wilt-associated virus (PMWaV) complex as well as PSVs. PMWaV-1, -3, and -6 presented recombination events across the quintuple gene block, while no recombination events were found for PMWaV-2. High recombination frequency of the RNA1 and RNA2 molecules from PSV-A and PSV-B were congruent with the diversity found by phylogenetic analyses. Here, we also report the development and improvement of RT-PCR diagnostic protocols for the specific identification and detection of viruses infecting pineapple based on the diverse viral populations characterized in this study. Given the high occurrence of recombination events, diversity, and discovery of viruses found in Ananas germplasm, the reported and validated RT-PCR assays represent an important advance for surveillance of viral infections of pineapple.
Collapse
|
3
|
Kwibuka Y, Bisimwa E, Blouin AG, Bragard C, Candresse T, Faure C, Filloux D, Lett JM, Maclot F, Marais A, Ravelomanantsoa S, Shakir S, Vanderschuren H, Massart S. Novel Ampeloviruses Infecting Cassava in Central Africa and the South-West Indian Ocean Islands. Viruses 2021; 13:v13061030. [PMID: 34072594 PMCID: PMC8226816 DOI: 10.3390/v13061030] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/24/2021] [Accepted: 05/25/2021] [Indexed: 11/30/2022] Open
Abstract
Cassava is one of the most important staple crops in Africa and its production is seriously damaged by viral diseases. In this study, we identify for the first time and characterize the genome organization of novel ampeloviruses infecting cassava plants in diverse geographical locations using three high-throughput sequencing protocols [Virion-Associated Nucleotide Acid (VANA), dsRNA and total RNA], and we provide a first analysis of the diversity of these agents and of the evolutionary forces acting on them. Thirteen new Closteroviridae isolates were characterized in field-grown cassava plants from the Democratic Republic of Congo (DR Congo), Madagascar, Mayotte, and Reunion islands. The analysis of the sequences of the corresponding contigs (ranging between 10,417 and 13,752 nucleotides in length) revealed seven open reading frames. The replication-associated polyproteins have three expected functional domains: methyltransferase, helicase, and RNA-dependent RNA polymerase (RdRp). Additional open reading frames code for a small transmembrane protein, a heat-shock protein 70 homolog (HSP70h), a heat shock protein 90 homolog (HSP90h), and a major and a minor coat protein (CP and CPd respectively). Defective genomic variants were also identified in some cassava accessions originating from Madagascar and Reunion. The isolates were found to belong to two species tentatively named Manihot esculenta-associated virus 1 and 2 (MEaV-1 and MEaV-2). Phylogenetic analyses showed that MEaV-1 and MEaV-2 belong to the genus Ampelovirus, in particular to its subgroup II. MEaV-1 was found in all of the countries of study, while MEaV-2 was only detected in Madagascar and Mayotte. Recombination analysis provided evidence of intraspecies recombination occurring between the isolates from Madagascar and Mayotte. No clear association with visual symptoms in the cassava host could be identified.
Collapse
Affiliation(s)
- Yves Kwibuka
- Plant Pathology Laboratory, TERRA-Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés, 2, 5030 Gembloux, Belgium; (A.G.B.); (F.M.)
- Faculté des Sciences Agronomiques, Université Catholique de Bukavu, BP 285 Bukavu, Democratic Republic of the Congo;
- Correspondence: (Y.K.); (S.M.)
| | - Espoir Bisimwa
- Faculté des Sciences Agronomiques, Université Catholique de Bukavu, BP 285 Bukavu, Democratic Republic of the Congo;
| | - Arnaud G. Blouin
- Plant Pathology Laboratory, TERRA-Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés, 2, 5030 Gembloux, Belgium; (A.G.B.); (F.M.)
| | - Claude Bragard
- Earth and Life Institute, Applied Microbiology-Phytopathology, UCLouvain, 1348 Louvain-la-Neuve, Belgium;
| | - Thierry Candresse
- Université Bordeaux, INRAE, UMR BFP, CS20032, CEDEX, 33882 Villenave d’Ornon, France; (T.C.); (C.F.); (A.M.)
| | - Chantal Faure
- Université Bordeaux, INRAE, UMR BFP, CS20032, CEDEX, 33882 Villenave d’Ornon, France; (T.C.); (C.F.); (A.M.)
| | - Denis Filloux
- CIRAD, UMR PHIM, 34090 Montpellier, France;
- PHIM Plant Health Institute, Université Montpellier, CIRAD, INRAE, Institut Agro, IRD, 34000 Montpellier, France
| | - Jean-Michel Lett
- CIRAD, UMR PVBMT, Pôle de Protection des Plantes, Saint-Pierre, F-97410 Ile de la Reunion, France;
| | - François Maclot
- Plant Pathology Laboratory, TERRA-Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés, 2, 5030 Gembloux, Belgium; (A.G.B.); (F.M.)
| | - Armelle Marais
- Université Bordeaux, INRAE, UMR BFP, CS20032, CEDEX, 33882 Villenave d’Ornon, France; (T.C.); (C.F.); (A.M.)
| | | | - Sara Shakir
- Plant Genetics Laboratory, TERRA-Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés, 2, 5030 Gembloux, Belgium; (S.S.); (H.V.)
| | - Hervé Vanderschuren
- Plant Genetics Laboratory, TERRA-Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés, 2, 5030 Gembloux, Belgium; (S.S.); (H.V.)
- Laboratory of Tropical Crop Improvement, Division of Crop Biotechnics, Biosystems Department, KU Leuven, 3000 Leuven, Belgium
| | - Sébastien Massart
- Plant Pathology Laboratory, TERRA-Gembloux Agro-Bio Tech, University of Liège, Passage des Déportés, 2, 5030 Gembloux, Belgium; (A.G.B.); (F.M.)
- Correspondence: (Y.K.); (S.M.)
| |
Collapse
|
4
|
Abstract
Mealybug wilt of pineapple (MWP) is a disease of pineapple that has a long history in Hawaii, but is present throughout the world where pineapples are grown in tropical regions. The disease has an interesting etiology that is poorly understood but involves an association with virus particles, mealybug vectors, and ants which spread the mealybug vectors. Several distinct pineapple mealybug wilt-associated virus (PMWaV) species have been identified thus far with potential further member species yet to be characterized. Pineapple mealybug wilt-associated viruses are member species of the Ampelovirus genus of the Closteroviridae family. Ampeloviruses are split into two subgroups, subgroup I and subgroup II. PMWaV-2 is a subgroup II member, and these have a longer and more complex genome with additional genes on the 3’ terminus of the RNA genome compared to subgroup I ampeloviruses. PMWaV-2, along with the presence of mealybug vectors, have been shown to be necessary factors in symptom development in Hawaii. Some of these extra genes in the 3’ of PMWaV-2 have recently been shown to function as silencing suppressors, and may play a role in the virulence of PMWaV-2 and symptom development. In other regions of the world, reports of symptomatic plants without PMWaV-2 infection, but with PMWaV-1, -3 or some combination, contradict the requirement of PMWaV-2 for symptom development in MWP. It is possible that further, uncharacterized PMWaVs may be present in symptomatic pineapple plants that test negative for PMWaV-2, explaining the inconsistency in symptom development. More research is necessary to explore the confusing etiology of the MWP disease, and to perhaps shed light upon the symptom development.
Collapse
|
5
|
Jarugula S, Gowda S, Dawson WO, Naidu RA. Development of infectious cDNA clones of Grapevine leafroll-associated virus 3 and analyses of the 5' non-translated region for replication and virion formation. Virology 2018; 523:89-99. [PMID: 30103103 DOI: 10.1016/j.virol.2018.07.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 07/19/2018] [Accepted: 07/21/2018] [Indexed: 01/28/2023]
Abstract
Infectious cDNA clones were developed for Grapevine leafroll-associated virus 3 (GLRaV-3, genus Ampelovirus, family Closteroviridae). In vitro RNA transcripts generated from cDNA clones showed replication via the production of 3'-coterminal subgenomic (sg) mRNAs in Nicotiana benthamiana protoplasts. The detection of sgRNAs and the recovery of progeny recombinant virions from N. benthamiana leaves agroinfiltrated with full-length cDNA clones confirmed RNA replication and virion formation. The 5' non-translated region (5' NTR) of GLRaV-3 was exchangeable between genetic variants and complement the corresponding cognate RNA functions in trans. Mutational analysis of the 5' NTR in minireplicon cDNA clones showed that the conserved 40 nucleotides at the 5'-terminus were indispensable for replication, compared to downstream variable portion of the 5' NTR. Some of the functional mutations in the 5' NTR were tolerated in full-length cDNA clones and produced sgRNAs and virions in N. benthamiana leaves, whereas other mutations affected replication and virion formation.
Collapse
Affiliation(s)
- Sridhar Jarugula
- Department of Plant Pathology, Irrigated Agriculture Research and Extension Center, Washington State University, WA 99350, United States
| | - Siddarame Gowda
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
| | - William O Dawson
- Citrus Research and Education Center, University of Florida, Lake Alfred, FL, United States
| | - Rayapati A Naidu
- Department of Plant Pathology, Irrigated Agriculture Research and Extension Center, Washington State University, WA 99350, United States.
| |
Collapse
|
6
|
Reynard JS, Schneeberger PHH, Frey JE, Schaerer S. Biological, Serological, and Molecular Characterization of a Highly Divergent Strain of Grapevine leafroll-associated virus 4 Causing Grapevine Leafroll Disease. PHYTOPATHOLOGY 2015; 105:1262-1269. [PMID: 25822183 DOI: 10.1094/phyto-12-14-0386-r] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The complete genome sequence of a highly divergent strain of Grapevine leafroll-associated virus 4 (GLRaV-4) was determined using 454 pyrosequencing technology. This virus, designated GLRaV-4 Ob, was detected in Vitis vinifera 'Otcha bala' from our grapevine virus collection at Agroscope. The GLRaV-4 Ob genome length and organization share similarities with members of subgroup II in the genus Ampelovirus (family Closteroviridae). Otcha bala was graft-inoculated onto indicator plants of cultivar Gamay to evaluate the biological properties of this new strain, and typical leafroll symptoms were induced. A monoclonal antibody for the rapid detection of GLRaV-4 Ob by enzyme-linked immunosorbent assay is available, thus facilitating large-scale diagnostics of this virus. Based on the relatively small size of the coat protein, the reduced amino acid identity and the distinct serological properties, our study clearly shows that GLRaV-4 Ob is a divergent strain of GLRaV-4. Furthermore, molecular and serological data revealed that the AA42 accession from which GLRaV-7 was originally reported is in fact co-infected with GLRaV-4 Ob and GLRaV-7. This finding challenges the idea that GLRaV-7 is a leafroll-causing agent.
Collapse
Affiliation(s)
- Jean-Sébastien Reynard
- First and fourth authors: Agroscope-Virology and Phytoplasmology, Nyon, Switzerland; second author: Swiss Tropical and Public Health Institute-Virology, Basel, Switzerland; and third author: Agroscope-Molecular Diagnostics, Genomics and Bioinformatics, Waedenswil, Switzerland
| | - Pierre H H Schneeberger
- First and fourth authors: Agroscope-Virology and Phytoplasmology, Nyon, Switzerland; second author: Swiss Tropical and Public Health Institute-Virology, Basel, Switzerland; and third author: Agroscope-Molecular Diagnostics, Genomics and Bioinformatics, Waedenswil, Switzerland
| | - Jürg Ernst Frey
- First and fourth authors: Agroscope-Virology and Phytoplasmology, Nyon, Switzerland; second author: Swiss Tropical and Public Health Institute-Virology, Basel, Switzerland; and third author: Agroscope-Molecular Diagnostics, Genomics and Bioinformatics, Waedenswil, Switzerland
| | - Santiago Schaerer
- First and fourth authors: Agroscope-Virology and Phytoplasmology, Nyon, Switzerland; second author: Swiss Tropical and Public Health Institute-Virology, Basel, Switzerland; and third author: Agroscope-Molecular Diagnostics, Genomics and Bioinformatics, Waedenswil, Switzerland
| |
Collapse
|
7
|
Dey KK, Lin H, Borth WB, Melzer MJ, Hu JS. A highly sensitive single-tube nested PCR assay for the detection of Pineapple mealybug wilt associated virus-2 (PMWaV-2). J Virol Methods 2012; 183:215-8. [PMID: 22484612 DOI: 10.1016/j.jviromet.2012.03.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2011] [Revised: 03/15/2012] [Accepted: 03/21/2012] [Indexed: 11/18/2022]
Abstract
An assay was developed for the detection of Pineapple mealybug wilt associated virus-2 (PMWaV-2), an important factor in the etiology of mealybug wilt of pineapple. The assay combines reverse transcription of RNA isolated from pineapple with a specific and very sensitive, single, closed-tube nested polymerase chain reaction (PCR) to amplify a segment of the coat protein gene of the PMWaV-2. The outer primers were designed to anneal at higher temperatures than the nested primers to prevent primer competition in consecutive amplification reactions. To reduce potential competition further, the outer primers were used at one-thousandth the concentration of the nested primers. The specificity and sensitivity of this assay are much greater than PCR using only a single primer-pair. A TaqMan(®) probe was also designed for use in quantitative PCR to detect and quantify the PCR amplification products directly in a single-tube assay. The advantages of the single-tube assays using both conventional and quantitative PCR are reduced handling time and prevention of cross contamination compared to regular nested PCR in which the reactions are carried out in two separate tubes.
Collapse
Affiliation(s)
- K K Dey
- Department of Plant and Environmental Protection Sciences, University of Hawaii at Manoa, 3190 Maile Way, Honolulu, HI 96822, USA
| | | | | | | | | |
Collapse
|
8
|
Hernández L, Ramos P, Rodríguez M, Peña I, Pérez J. First report of
Pineapple mealybug wilt associated virus‐3
infecting pineapple in Cuba. ACTA ACUST UNITED AC 2010. [DOI: 10.5197/j.2044-0588.2010.022.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- L. Hernández
- Research Institute on Tropical Fruit CropsP.O. Box 11 300, 7th Ave.# 3005PlayaHavana CityCuba
| | - P.L. Ramos
- Research Institute on Tropical Fruit CropsP.O. Box 11 300, 7th Ave.# 3005PlayaHavana CityCuba
| | - M. Rodríguez
- Research Institute on Tropical Fruit CropsP.O. Box 11 300, 7th Ave.# 3005PlayaHavana CityCuba
| | - I. Peña
- Research Institute on Tropical Fruit CropsP.O. Box 11 300, 7th Ave.# 3005PlayaHavana CityCuba
| | - J.M. Pérez
- Research Institute on Tropical Fruit CropsP.O. Box 11 300, 7th Ave.# 3005PlayaHavana CityCuba
| |
Collapse
|
9
|
Ghanem-Sabanadzovic NA, Sabanadzovic S, Uyemoto JK, Golino D, Rowhani A. A putative new ampelovirus associated with grapevine leafroll disease. Arch Virol 2010; 155:1871-6. [PMID: 20703503 PMCID: PMC2970810 DOI: 10.1007/s00705-010-0773-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Accepted: 07/24/2010] [Indexed: 11/30/2022]
Abstract
A putative new ampelovirus was detected in Vitis vinifera cv. Carnelian showing mild leafroll symptoms and molecularly characterized. The complete genome consisted of 13,625 nt and had a structure similar to that of members of subgroup I in the genus Ampelovirus (fam. Closteroviridae). In-depth analyses showed that the virus from cv. Carnelian is the most distinct member of the "GLRaV-4 lineage" of ampeloviruses, which comprises GLRaV-4, -5, -6, -9, and the recently characterized GLRaV-Pr, and GLRaV-De. This virus appears to be a new member of the family Closteroviridae, for which the provisional name grapevine leafroll-associated Carnelian virus is proposed.
Collapse
|
10
|
Sether DM, Borth WB, Melzer MJ, Hu J. Spatial and Temporal Incidences of Pineapple mealybug wilt-associated viruses in Pineapple Planting Blocks. PLANT DISEASE 2010; 94:196-200. [PMID: 30754271 DOI: 10.1094/pdis-94-2-0196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A complex of Pineapple mealybug wilt-associated viruses (PMWaVs) that can infect pineapple (Ananas comosus) is correlated with reduced yields and mealybug wilt of pineapple. The incidences of PMWaV-1 and PMWaV-2 at planting, fruit harvest, the beginning of the ratoon crop, and ratoon fruit harvest were determined for end, side, and central regions of planting blocks in eight commercial fields. Differences in virus incidence for the three regions at ratoon harvest were highly significant (P = 0.0018). Central regions of planting blocks had lower virus incidences at the time of ratoon fruit harvest. Collection of propagation material from the central regions of planting blocks will help to minimize PMWaV incidence in fields planted with this material.
Collapse
Affiliation(s)
- D M Sether
- University of Hawaii at Manoa, Plant and Environmental Protection Sciences, Honolulu 96822
| | - W B Borth
- University of Hawaii at Manoa, Plant and Environmental Protection Sciences, Honolulu 96822
| | - M J Melzer
- University of Hawaii at Manoa, Plant and Environmental Protection Sciences, Honolulu 96822
| | - J Hu
- University of Hawaii at Manoa, Plant and Environmental Protection Sciences, Honolulu 96822
| |
Collapse
|