Mealybug Wilt Of Pineapple Research Articles

Economically Imperative Ananas comosus Diseases, Status, and Its Control Measures Documented in Producing Countries

Ananas comosus, commonly known as pineapple, is a fruit with a large potential market as a commodity and commercial fruit. Numerous pests and diseases affect pineapple, directly or indirectly, by lowering the quality and quantity. The fungal causative agents, namely Fusarium ananatum and Thalaromyces stolii (previously named Penicillium funiculosum), cause fruitlet core rot (FCR) and fusariosis by Fusarium guttiforme. Bacteria heart rot (BHR) is an infection by Erwinia chrysanthemi, newly known as Dickeya zeae. Nevertheless, the mealybug wilt of pineapple (MWP) is another pineapple treat to susceptible pineapple varieties caused by pineapple mealybug wilt-associated viruses (PMWaVs). Other diseases include destruction caused by pathogenic nematodes. This review discusses the status of these diseases and the control measures that greatly affect the economy of pineapple-producing countries due to the economic significance of these crops. Growers need up-to-date information on the identity of the diseases that affect pineapple crops in the various countries that produce them to effectively manage the diseases in the field.

Ecologically Based Management of Pineapple Mealybug Wilt: Controlling Dysmicoccus brevipes Mealybug Populations with Salicylic Acid Analogs and Plant Extracts

Mealybug wilt of pineapple (MWP) is a destructive disease worldwide caused by a parasitic complex that includes Pineapple Mealybug Wilt-associated Viruses (PMWaVs) and mealybugs (Dysmicoccus brevipes), which concurrently act as vectors for these viruses. Reducing the mealybug population is key to managing MWP, which is achieved in intensive production systems through the use of insecticides. SA (salicylic acid), ASM (acibenzolar-S-methyl), BABA (β-aminobutyric acid), and MeSA (methyl salicylate) are key components of systemic acquired resistance (SAR), the defense mechanism of plants against biotrophic agents such as mealybugs. In this study, these compounds were applied either as pure chemicals and/or as a major constituent of plant extracts. Both the Hawaiian hybrid MD-2 and Queen Victoria tissue culture plants, as well as suckers used for vegetative propagation, were treated with these compounds by direct application on the soil of pineapple pots. Subsequently, five mealybugs were released on each plant or each daughter plant in case of a transgenerational experiment; then, after 45 days, the number of mealybugs was counted. Exogenous SA, ASM, and MeSA reduced the population of mealybugs by a minimum of 50% and up to 80%. These SAR-inducing treatments could be an interesting alternative for controlling mealybugs and are already used in other pathosystems. The SAR mechanisms behind this effect are yet to be confirmed by molecular and enzymatic markers. ASM and MeSA are promising treatments for pineapples using tissue culture plants or traditional shoots.

Determination of Mealybug Population Density for Transmission of Pineapple Mealybug Wilt Disease in Central Uganda

Pineapple mealybug wilt disease (PMWD) is a complex and most destructive viral disease constraining pineapple production world over. Pineapple mealybug wilt disease is transmitted by mealybugs (Dysmicoccus species). Currently, in Uganda, the population of Dysmicoccus brevipes that can transmit PMWD is not known. Yet, closing this knowledge gap would provide a better understanding of PMWD etiology and development of sound management strategies. Experiment was laid out in a completely randomized design (CRD) with four replications in the screenhouse at the Faculty of Agriculture, Kyambogo University during the period 2017 and 2018. Pineapple variety Smooth Cayenne was inoculated with five levels of viruliferous mealybugs including one (1), five (5), ten (10), fifteen (15), and a control (uninoculated). Data collection commenced on symptoms appearance and continued on a 15-day interval for a period of two months. Data were collected on the incidence and severity of PMWD. All the data collected were analysed using Genstat computer programme. Results showed that the number of mealybugs significantly (p<0.05) affected the incidence and severity of PMWD during both trials. Although one viruliferous mealybug was able to transmit PMWD virus, the efficacy of transmission was recorded with the highest number of mealybugs per plant. It was, therefore, concluded that the higher the number of viruliferous mealybugs colonising a pineapple plant, the higher the incidence and severity of PMWD. The result of this study, therefore, adds to the pool of knowledge on the understanding the population density of mealybugs transmitting PMWD as well as provide insights to improvement of mealybug vector monitoring as a key component of integrated PMWD management.

First report of the Pineapple mealybug wilt‐associated viruses 1, 2 and 3 causing pineapple mealybug wilt disease in East Malaysia, Borneo

First report of the <i>Pineapple mealybug wilt‐associated viruses 1</i>, <i>2</i> and <i>3</i> causing pineapple mealybug wilt disease in East Malaysia, Borneo

Occurrence and distribution of pineapple mealybug wilt-associated viruses (PMWaVs) in MD2 pineapple fields in the Valle del Cauca Department, Colombia

MD2 pineapple production in the Valle del Cauca Department, Colombia, has increased in recent years due to its preference in the national and international markets. Pineapple mealybug wilt (PMW), reported in all production areas around the world, is associated with two mealybug species, Dysmicoccus brevipes and D. neobrevipes, and a group of virus species known as pineapple mealybug wilt-associated viruses (PMWaVs). In a previous study, D. brevipes was determined to be the main mealybug species associated with pineapples in the region; hence, the objective of this study was to determine the occurrence and distribution of PMWaVs in pineapple plants and specimens of D. brevipes collected in five MD2 pineapple fields in the Department of Valle del Cauca. Our results confirmed the presence of three virus species in both plant and mealybug specimens. PMWaV3 showed the highest detection frequencies (92.6% and 88.7%), followed by PMWaV1 (26.5% and 8.3%) and PMWaV2 (12.0% and 2.0%) in plant and mealybug samples, respectively. Mixed infections of PMWaVs were found also in the studied plant material. The most common virus association consisting of PMWaV1 and PMWaV3 was found in 30 plant samples (20%). The correlation analysis between each virus species found in mealybugs and their pineapple host suggests that PMWaV3 is not only transmitted through infested plant material, but that D. brevipes may also play a role in the dynamics of disease dissemination. The results of this study contribute to the understanding of PMWaV transmission in MD2 pineapple-cultivated areas in the Valle del Cauca region.

Pineapple mealybug wilt-associated viruses (pineapple mealybug wilt (PMBW))

Pineapple mealybug wilt-associated viruses (pineapple mealybug wilt (PMBW))

A novel ampelovirus associated with mealybug wilt of pineapple (Ananas comosus).

Mealybug wilt of pineapple (MWP) is the most important and complex viral disease affecting pineapple worldwide. High-throughput sequencing was conducted to characterize a new virus identified only in symptomatic pineapple plants and tentatively named pineapple mealybug wilt-associated virus 6 (PMWaV-6). Data analyses revealed a genome of 17,854 nucleotides with an organization resembling members of the genus Ampelovirus, family Closteroviridae. Encoded proteins shared sequence identity with the corresponding proteins of grapevine leafroll-associated virus 3, blackberry vein banding-associated virus, and PMWaV-2. The present study reports the discovery of PMWaV-6, a putative and distinct new member of the genus Ampelovirus, subgroup I, its potential involvement in MWP, and the development of PMWaV-6-specific RT-PCR assays to detect and monitor this virus in field samples.

Prevalence of Dysmicoccus brevipes (Cockerell, 1893) (Hemiptera: Pseudococcidae) in MD2 pineapple crop areas in Colombia

ABSTRACT Pineapple mealybug wilt has been reported as one of the most important diseases affecting pineapple crops worldwide. This study aimed to determine the prevalence of mealybugs associated with two agroclimatic zones of pineapple production in the department of Valle del Cauca, Colombia. The survey was conducted in the upper (Dagua, Restrepo, La Cumbre and Vijes) and lower (Buga and Palmira) land zones. A total of 75 MD2 pineapple plots in different development growth stages were evaluated. The mealybugs were recorded mainly in the upper land zone, with a prevalence of 32 %. Concerning the plots growth stages, the highest prevalence was observed in second-cycle plots (13.3 %), followed by third-cycle ones, including abandoned plots (9.3 %), and first-cycle plots (6.7 %), which were associated with the use of pesticides. Dysmicoccus brevipes was the only mealybug species (Pseudococcidae) found on pineapples in the study area.

Comparison of shoot tip culture and cryotherapy for eradication of ampeloviruses associated with Pineapple mealybug wilt in wild varieties

The Pineapple mealybug wilt-associated virus (PMWaV) provokes a disease that causes considerable losses to pineapple growers due to the reduced leaf tissue turgescence, resulting in leaf necrosis and death in severe cases. In this work, we describe the comparison of shoot tip culture and cryotherapy methods to eradicate the pineapple wilt disease-associated ampeloviruses. Plants from the accessions Ananas comosus var. comosus (AGB-009), var. bracteatus (AGB-119), and var. parguazensis (AGB-376) were indexed by RT-PCR, confirming mixed infections of PMWaV-1, PMWaV-2, and PMWaV-3. The accessions were cultured in vitro and their shoot tips treated by cryotherapy following a droplet vitrification protocol. The regeneration rate from shoot tip culture was 93% for AGB-376 and 100% for the other two accessions. After freezing, AGB-376 had 100% regeneration subsequent to exposure to PVS2 for 45 min, followed by 95% for AGB-009, while for AGB-119 the optimal exposure time was 60 min, with plant regeneration from nearly 80% of the shoot tips. For the accessions AGB-009 and AGB-376, all the recovered plants were virus free by the two methods, while 50% of the plants from accession AGB-119 remained infected. These results indicate that shoot tip culture alone or in association with cryotherapy is a promising routine method for virus removal from pineapple plant tissues and is useful to ensure that backup reserves of pineapple germplasm, conserved by in vitro bank and cryobank, are formed with virus-free plants.

First report of Pineapple mealybug wilt associated virus‐2 infecting pineapple in Ghana

Mealybug wilt of pineapple (MWP) is a major viral disease of pineapple (Ananas comosus) worldwide, including Ghana (Sether & Hu, 2002; Sarpong et al., 2017). In Ghana, MWP causes yield loss estimated at about US$248 per hectare…

First report of Pineapple mealybug wilt‐associated virus‐1 and ‐3 in Ghanaian pineapple

Mealybug wilt of pineapple (MWP) is a destructive viral-associated disease affecting pineapple (Ananas comosus) production in many growing regions worldwide, including Ghana (Sarpong et al., 2017; Dey et al., 2018). In Hawaii, MWP…

The viral complex associated with mealybug wilt disease of pineapple in Cuba

Mealybug wilt of pineapple (MWP) disease has been associated with the infection by a complex of ampeloviruses (Pineapple mealybug wilt-associated virus 1 (PMWaV-1), PMWaV-2, PMWaV-3, PMWaV-4 and PMWaV-5)) (Closteroviridae) and badnaviruses (Pineapple bacilliform CO virus (PBCOV) and Pineapple bacilliform ER virus (PBERV) (Caulimoviridae)). In Cuba, PMWaV-1, PMWaV-2, PMWaV-3 and PBCOV are widespread in commercial pineapple fields, but the association of these viruses with the aetiology of the disease remains unknown. During 2009 to 2012, a survey to detect PMWaV-1, PMWaV-2 and PMWaV-3 by RT-PCR, and PBCOV by non-radioactive Dot Blot hybridization was carried out on samples collected from asymptomatic or MWP symptomatic pineapple plants from 24 commercial fields in 10 provinces and Isla de la Juventud. PMWaV-1, PMWaV-2, PMWaV-3, and PBCOV occurred in simple or mixed infections, whereas PMWaV-2 was the viral species most frequently detected in symptomatic plants. The positive or negative diagnostic results of the RT-PCR to detect PMWaV-2 was more reliably associated with the MWP symptomatic or asymptomatic status of the sampled plants, respectively, than those from PMWaV-1, PMWaV-3 or PBCOV detection techniques. This work discloses the correlation between the infection by PMWaV-2 and the presence of MWP symptoms in Cuba, supporting previous studies indicating the major role of this virus triggering MWP disease.

Bioinformatics approach to the study of the molecular behaviour of mealybug wilt of pineapple

Mealybug wilt of pineapple (MWP) is a disease caused by the Pineapple mealybug wilt-associated virus (PMWaV) complex transmitted by Dysmicoccus brevipes and D. neobrevipes. MWP symptoms are characterized by root dessication, leaf wilting and consequent failure to produce a fruit. The molecular mechanisms involved in the pineapple-PMWaV interaction for MWP symptomatology are still unclear. In this work, mRNAs of asymptomatic and symptomatic pineapple plants were evaluated using Illumina RNA sequencing technology. From a total of 79 million reads per sample, 16,097 genes were identified using STAR aligner and HTseq for paired-end files. Differentially expressed genes (DEGs) between the evaluated groups were estimated using DESeq2 and edgeR, with an FDR cutoff of ≤0.05. A total of 207 DEGs were detected, with 61 upregulated and 146 downregulated in symptomatic plants infected by PMWaV-2. The methodologies improved by the assays presented in this article and the detected DEGs can substantiate further researches with pineapple and the MWP disease.

Mealybug Wilt of Pineapple and Associated Viruses

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.

ELIMINASI PINEAPPLE MEALYBUG WILT-ASSOCIATED-VIRUS (PMWaV) DARI TANAMAN NANAS DENGAN HOT WATER TREATMENT

[ELIMINATION OF Pineapple Mealybug Wilt-associated Virus (PMWaV) FROM PINEAPPLE PLANT BY HOT WATER TREATMENT]. Mealybug wilt of pineapple (MWP) is a devastating disease found in all the major pineapple growing regions. Closterovirus particles can be detected in both MWP symptomatic and asymptomatic pineapple. Rogue of symptomatic plants is the simplest method of controlling MWP disease, but this method is less effective as PMWaV might remains at asymptomatic plants. Use of pesticide to control mealybug and ants is not efficient and high cost. The research was conducted to develop elimination method for PMWaV-free plant by hot water treatment. PMWaV infected plant parts (leave, stem, crown) were exposed to two hot water treatments, consisting of 35 oC for 24 hour as pre-treatment and immediately followed by hot water treatment either 56 oC for 60 minute or 58 oC for 40 minute in a water bath. The infected plant without hot water treatment served as the positive control, and healthy plant without hot water treatment as the negative control. PMWaV infection could be eliminated from propagative material through hot water treatment 58 oC 40 minute in a water bath without decrease propagative material viability.

Perception of Mealybug Wilt Effect and Management among Pineapple Farmers in Ghana

Mealybug wilt of pineapple (MWP) is a major viral disease of pineapple [Ananas comosus (L) Merr.] in Ghana. Its incidence and extent of damage have not been extensively studied in the country. The study was conducted to determinepineapple farmers’ perception on the effect and management of the MWPdisease in Ghana. Structured interview schedule and questionnaires were used to solicit information from 227 pineapple farmers in the Central and Eastern regions of Ghana. Data collected were analysed using descriptive statistics into percentage, mean and standard deviation.The majority(73.1%) of the respondents aged between 31 and 50 years and were mainly Senior Secondary or Senior High School leavers (52.2%) who had been growing pineapples between 5 and 20years (82.6%). All respondents indicated that they had experienced the MWP in their pineapple farms and were able to give a vivid description of the disease symptoms. The farmers further indicated that the severity of MWP was high in Smooth cayenne (100%), sugar loaf (96.9%) and Queen Victoria (91.2%) but low in MD2 (%??) varieties of pineapple. More than two-thirds of respondents indicated that they were losing between 1% and 20% of their yield per hectare and up to GHȻ 1000.00 per hectare to the disease. The majority of the respondents manage MWP in their farms by practicing land fallowing, avoiding infected mother plots for suckers, treat soil, mother plots and suckers with insecticides, to destroy mealybug vectors and their ant symbionts.

Prevalence De La Maladie Du Deperissement De L’ananas (Wilt) Et Perception Des Producteurs Au Benin

Pineapple [Ananas comosus (L.) Merril], cultivated in Benin for it economical importance is affected by Pineapple mealybug wilt, a viral disease. The objectives of this study were to evaluate the determining factors of its prevalence and farmers knowledge on the disease. To achieve these, a total number of 180 farmers, distributed in five communes of southern Benin have been interviewed in 2014 and 2015. In order to identify factors that influence the disease distribution, generalized linear models with the binomial and multinomial distribution family were used to explain the effect of the variables (field and plant levels) and disease severity, respectively. Only factors ‘commune’ 'and' year ' had a significant effect on the incidence at field level (69% in 2014 and 78% in 2015) while three predictors (township, year and variety) explained the severity of the disease and the interaction year -township was significant. Farmers perceive the disease and attribute five causes responsible for its expression. They use height methods to manage the disease. These findings constitute a qualitative as well as quantitative information to build on in designing methods of controlling the disease in order to boost the productivity of pineapple in Benin.

Detection of Pineapple mealybug wilt-associated virus 1 and 3 in Mexico

&lt;p&gt;In El Bajo Papaloapan, the main producing area of pineapple of Mexico, leaves with typical symptoms of viral infection consisting in chlorosis, flaccidity, reduced growth and reddening were collected. By RT-PCR with specific primers for the hsp70 gene and subsequent sequencing were detected Pineapple mealybug wilt virus associated-virus 1 (PMWaV-1) and Pineapple mealybug wilt virus associated-3 (PMWaV-3). From the sequences obtained a tree was done with sequences from different regions of the world available in GenBank in order to know their similarity. The sequence obtained from the Mexican isolate PMWaV-1 was genetically related to the sequences of isolates from Cuba, Taiwan, Thailand and Hawaii and more distant from the Australian isolate. The sequence obtained for the Mexican isolate PMWaV-3 was more related to isolates from Hawaii, Cuba, Australia and Taiwan and more distant from the Thailand isolate. This is the first report of the presence of these two viruses in Mexico.&lt;/p&gt;

Analysis of pineapple mealybug wilt associated virus -1 and -2 for potential RNA silencing suppressors and pathogenicity factors.

Higher plants use RNA silencing to defend against viral infections. As a counter defense, plant viruses have evolved proteins that suppress RNA silencing. Mealybug wilt of pineapple (MWP), an important disease of pineapple, has been associated with at least three distinct viruses, Pineapple mealybug wilt associated virus -1, -2, and -3 (PMWaV-1, -2, and -3). Selected open reading frames (ORFs) of PMWaV-1 and PMWaV-2 were screened for their local and systemic suppressor activities in Agrobacterium-mediated transient assays using green fluorescent protein (GFP) in Nicotiana benthamiana. Results indicate that PMWaV-2 utilizes a multiple-component RNA silencing suppression mechanism. Two proteins, p20 and CP, target both local and systemic silencing in N. benthamiana, while the p22 and CPd proteins target only systemic silencing. In the related virus PMWaV-1, we found that only one of the encoded proteins, p61, had only systemic suppressor activity. Of all the proteins tested from both viruses, only the PMWaV-2 p20 protein suppressed local silencing induced by double-stranded RNA (dsRNA), but only when low levels of inducing dsRNA were used. None of the proteins analyzed could interfere with the short distance spread of silencing. We examined the mechanism of systemic suppression activity by investigating the effect of PMWaV-2-encoded p20 and CP proteins on secondary siRNAs. Our results suggest that the PMWaV-2 p20 and CP proteins block the systemic silencing signal by repressing production of secondary siRNAs. We also demonstrate that the PMWaV-2 p20 and p22 proteins enhanced the pathogenicity of Potato virus X in N. benthamiana.

First report of Pineapple mealybug wilt associated virus‐1 in Ecuador

In Ecuador, where pineapple represents one of the most important export commodities, virus testing has been neglected. In July 2014, a total of twenty MD2 hybrid pineapple plants showing virus-like symptoms (Fig. 1) were collected from a…