Kirk, A. A., Lacey, L. A., Brown, J. K., Ciomperlik, M. A., Goolsby, J. A., Vacek, D. C., Wendel, L. E., & Napompeth, B. (2000). Variation in the Bemisia tabaci s. 1. species complex (Hemiptera: Aleyrodidae) and its natural enemies leading to successful biological control of Bemisia biotype B in the USA. Bulletin of Entomological Research, 90(4), 317-327.
PMID: 11020790;Abstract:
Parasitoids of the Bemisia tabaci (Gennadius) species complex collected in Spain and Thailand were evaluated as biological control agents of B. tabaci biotype B in cole crops in Texas, USA. Parasitoids were identified by morphological and RAPD-PCR analyses. The most abundant parasitoid from Spain was Eretmocerus mundus Mercet with apparent field parasitism of 39-44%. In Thailand, Encarsia formosa Gahan, E. transvena Timberlake, E. adrianae Lopez-Avila, Eretmocerus sp. 1 and sp. 2 emerged, with apparent field parasitism of 1-65%. Identification and molecular classification of B. tabaci associated with parasitoid collections and in the release site in Texas were accomplished using morphological traits and nucleotide sequence comparison of the mitochondrial cytochrome oxidase I gene (COI) (700-720 bp). Collections of B. tabaci from Thailand grouped separately from B types from Arizona and Florida and the target B type from Texas, USA, a cluster from India, and other New World B. tabaci. The Spanish B. tabaci host of E. mundus which was laboratory and field-tested to achieve biological control of the B type was most closely related to non-B type B. tabaci populations from Spain and Sudan, the latter which formed a second group within the larger clade that also contained the B type cluster. Laboratory tests indicated that E. mundus from Spain parasitized more B. tabaci type B than did Eretmocerus spp. native to Texas and other exotic parasitoids evaluated. Eretmocerus mundus from Spain also successfully parasitized B, tabaci type B when field-released in a 0.94 million ha test area in Texas, and has significantly enhanced control of B. tabaci type B in California, USA. In contrast, parasitoids from Thailand failed to establish in the field in Texas, collectively suggesting a positive correlation between the centres of diversity of compatible parasitoid-host complexes.
Brown, J. K. (2017). Engineered disease resistance in cotton using RNA-interference to knock down Cotton leaf curl Kokhran virus-Burewala and Cotton leaf curl Multan betasatellite expression. Viruses, 9(9), 257.
Briddon, R. W., Brown, J. K., Moriones, E., Stanley, J., Zerbini, M., Zhou, X., & Fauquet, C. M. (2008). Recommendations for the classification and nomenclature of the DNA-β satellites of begomoviruses. Archives of Virology, 153(4), 763-781.
PMID: 18247103;Abstract:
The symptom-modulating, single-stranded DNA satellites (known as DNA-β) associated with begomoviruses (family Geminiviridae) have proven to be widespread and important components of a large number of plant diseases across the Old World. Since they were first identified in 2000, over 260 full-length sequences (∼1,360 nucleotides) have been deposited with databases, and this number increases daily. This has highlighted the need for a standardised, concise and unambiguous nomenclature for these components, as well as a meaningful and robust classification system. Pairwise comparisons of all available full-length DNA-β sequences indicate that the minimum numbers of pairs occur at a sequence identity of 78%, which we propose as the species demarcation threshold for a distinct DNA-β. This threshold value divides the presently known DNA-β sequences into 51 distinct satellite species. In addition, we propose a naming convention for the satellites that is based upon the system already in use for geminiviruses. This maintains, whenever possible, the association with the helper begomovirus, the disease symptoms and the host plant and provides a logical and consistent system for referring to already recognised and newly identified satellites. © 2008 Springer-Verlag.
Brown, J. K. (2013). A genome-wide pairwise-identity-based proposalfor the classification of viruses in the genus, Mastrevirus (family, Geminiviridae).. Archives of Virology, 158:(1411-1424).
Muhire, B., D.P. Martin, J.K. Brown, J. Navas-Castillo, E. Moriones, F.M. Zerbini, R. Rivera-Bustamante,
V. G. Malathi, R. W. Briddon, and A. Varsani. 2013. A genome-wide pairwise-identity-based proposal for the classification of viruses in the genus, Mastrevirus (family, Geminiviridae). Arch Virol. 158:1411-1424.
Brown, J. K. (1998). Global diversity and distribution of whitefly-transmitted geminiviruses of cotton. Proceedings of the 1998 beltwide cotton conferences, San Diego, CA, USA, January 5-9 1999, 155-161.
Abstract:
Geminivrus diseases of cotton are on the rise, worldwide, yet few have been studied in adequate detail to permit the implementation of rational approaches to disease control. The rising costs of managing the whitefly vector, coupled to substantial losses caused by geminivirus-incited diseases now hinder cotton production by requiring inputs that are beyond economic feasibility. The requirement for geminivirus disease resistance in numerous cotton cultivars and multiple, diverse geographic cotton production areas of the world presents a new and unique challenge. To meet this need, baseline information concerning the identity, the distribution, and the relevant characteristics of cotton-infecting geminiviruses and virus strains, thereof, are now required. This study addresses this problem by attaining and applying molecular sequence analysis to key regions of the genomes of cotton-infecting geminivirus collected from cotton growing regions of the world. Specifically, we are examining the sequence similarities of the conserved the coat protein or AV1 gene, and the similarities and particular features associated with diagnostic nucleotides found in the LIR/CR that are involved in regulating essential aspects of the disease cycle. This effort represents the first cataloging and mapping of geminivirus identity and distribution, and the first investigation of the breadth of germiniviral relationships, or the 'diversity' of geminiviruses of cotton, worldwide. It seeks to understand relationships between cotton-infecting geminiviruses and of these viruses and other well-characterized or 'reference' geminiviruses from diverse crop and weed species. This data base of molecular and biotic information will serve as the cornerstone for the rational selection of virus species and strains toward developing cotton cultivars with resistance customized to protect against disease caused by geminiviruses relevant to the production area. This approach will also permit the first precise evaluation of the breadth of disease resistance in a cultivar by permitting challenge-inoculation with narrowly and broadly divergent virus genotypes, thereby providing both a predictive capacity for sustainability of disease resistance and a safeguard to achieve long term protection against indigenous and introduced, exotic geminiviruses of cotton.
