Rhizosphere interactions are an understudied component of citrus production. This is even more important in Florida flatwood soils, which pose significant challenges in achieving sustainable and effective fruit production due to low natural fertility and organic matter. Citrus growers apply soil amendments, including oak mulch, to ameliorate their soil conditions.
View Article and Find Full Text PDF, the tea shot-hole borer (TSHB), is an invasive ambrosia beetle that vectors several fungal pathogens that cause branch dieback in avocado trees in southern Florida. This study assessed the potential of four commercial products containing the entomopathogenic fungus () for managing adult TSHB beetles. Formulated products containing strains to which adult beetles were exposed were BioCeres WP, BotaniGard WP, BotaniGard ES, and Velifer ES.
View Article and Find Full Text PDFPicorna-like viruses of the order Picornavirales are a poorly defined group of positive-sense, single-stranded RNA viruses that include numerous pathogens known to infect plants, animals, and insects. A new picorna-like viral species was isolated from the wild lime psyllid (WLP), Leuronota fagarae, in the state of Florida, USA, and labelled: Leuronota fagarae picorna-like virus isolate FL (LfPLV-FL). The virus was found to have homology to a picorna-like virus identified in the Asian Citrus Psyllid (ACP), Diaphorina citri, collected in the state of Florida.
View Article and Find Full Text PDFThe spatial arrangement and growth pattern of root systems, defined by the root system architecture (RSA), influences plant productivity and adaptation to soil environments, playing an important role in sustainable horticulture. Florida's peach production area covers contrasting soil types, making it necessary to identify rootstocks that exhibit soil-type-specific advantageous root traits. In this sense, the wide genetic diversity of the genus allows the breeding of rootstock genotypes with contrasting root traits.
View Article and Find Full Text PDFRootstocks are fundamental for peach production, and their architectural root traits determine their performance. Root-system architecture (RSA) analysis is one of the key factors involved in rootstock selection. However, there are few RSA studies on spp.
View Article and Find Full Text PDFBackground: Huanglongbing, a devastating disease of citrus, is caused by the obligate, intracellular bacterium "Candidatus Liberibacter asiaticus" (CLas). CLas is transmitted by Diaphorina citri, the Asian citrus psyllid. Development of transmission-blocking strategies to manage huanglongbing relies on knowledge of CLas and D.
View Article and Find Full Text PDFThis study aimed to determine the inhibitive or stimulatory effects of leaf extracts from two subspecies on the hyphal growth of two well-known entomopathogenic fungi, and Extract concentrations of 50, 25, and 10% / based on leaf fresh weight were prepared from turnip ( subspecies ) and bok choy ( subspecies ) leaves. Each concentration was individually incorporated into potato dextrose agar plates for in vitro bioassays. The center of each plate was inoculated with 20 µL of a fungal suspension that was allowed 24 h to soak into the agar before sealing the plates and incubating them at 25 °C under a 14-h photophase.
View Article and Find Full Text PDFTraditionally, peach rootstocks are propagated by seeds due to their high availability, low cost, and easy storage and handling. However, stem cuttings allow the propagation of interspecific hybrids and keep the genetic uniformity of heterozygous genotypes. This study compared the effect of four different concentrations of K-IBA (indole-3-butyric acid potassium salt) on softwood cuttings of three peach backcrosses (peach × (peach × almond)) for rootstock propagation in two propagation systems: aeroponics and germination trays.
View Article and Find Full Text PDFis an obligate biotrophic fungal pathogen that causes orange rust of sugarcane, which is prevalent in many countries around the globe. In the United States, orange rust was first detected in sugarcane in Florida in 2007 and poses a persistent and economically damaging threat to the sugarcane industry in this region. Here, we generated the first genome assemblies for two isolates of (1040 and 2143) collected in Florida in 2017 from two sugarcane cultivars, CL85-1040 and CP89-2143, respectively.
View Article and Find Full Text PDFEntomopathogenic fungi can be a useful resource for controlling insect vectors of citrus plant pathogens, such as the Asian citrus psyllid () associated with huanglongbing or the citrus root weevil () associated with the spread of spp. In this study, () was investigated as a potential endophytic entomopathogenic fungus and various inoculation techniques were used to determine if it would colonize the Carrizo citrange () seeds and plants. The four inoculation methodologies evaluated were seed soaking, stem injection, foliar spray, and soil drench.
View Article and Find Full Text PDFis a fungal pathogen associated with perennial tropical fruit plants worldwide. In citrus, causes stem-end rot (Diplodia stem-end rot), a damaging postharvest disease that is aggravated when trees are also infected with the citrus greening bacteria ' Liberibacter asiaticus'. Due to the latent infection of during the preharvest stage, it becomes difficult to control the disease by chemical or physical treatment.
View Article and Find Full Text PDFis an obligate biotrophic oomycete that causes downy mildew (DM), one of the most destructive diseases of cultivated hop that can lead to 100% crop loss in susceptible cultivars. We used the published genome of to predict the secretome and effectorome and analyze the transcriptome variation among diverse isolates and during infection of hop leaves. Mining the predicted coding genes of the sequenced isolate OR502AA of .
View Article and Find Full Text PDFReproduction is a critical feature in the search for means to manage the Asian citrus psyllid, vector of a devastating bacterial pathogen of citrus. The importance of accuracy in functional, anatomical descriptions and interpretations for use by other disciplines, particularly molecular genetics, cannot be overstressed. The term 'sperm pump' was coined by classical authors on observational appearance of the endoskeleton of the male reproductive apparatus.
View Article and Find Full Text PDFCitrus greening, also called Huanglongbing (HLB), is one of the most destructive citrus diseases worldwide. It is caused by the fastidious gram-negative α-proteobacteria bacterium Candidatus Liberibacter asiaticus (CLas) and vectored by the Asian citrus psyllid (ACP), Diaphorina citri. Currently, there is no cure for HLB, no compounds have been successful in controlling HLB, and no sustainable management practices have been established for the disease.
View Article and Find Full Text PDFspecies hybrids have been repeatedly reported as causing damaging diseases to cultivated and wild plants. Two known hybrids, and × , are pathogens of Solanaceae and ornamentals, respectively, although the extent of their host ranges are unknown. emerged from hybridization of and an unidentified related species, whereas × emerged from and .
View Article and Find Full Text PDFBackground: Citrus Huanglongbing (HLB) is a bacterial disease with high economic significance. The associated agent Candidatus Liberibacter asiaticus is a fastidious, phloem-limited, intracellular bacterium that is transmitted by an insect vector the Asian citrus psyllid (ACP). The genome of Ca.
View Article and Find Full Text PDFThe oomycete pathogen Phytophthora cactorum causes crown rot, a major disease of cultivated strawberry. We report the draft genome of P. cactorum isolate 10300, isolated from symptomatic Fragaria x ananassa tissue.
View Article and Find Full Text PDFBackground: Outbreaks caused by asexual lineages of fungal and oomycete pathogens are a continuing threat to crops, wild animals and natural ecosystems (Fisher MC, Henk DA, Briggs CJ, Brownstein JS, Madoff LC, McCraw SL, Gurr SJ, Nature 484:186-194, 2012; Kupferschmidt K, Science 337:636-638, 2012). However, the mechanisms underlying genome evolution and phenotypic plasticity in asexual eukaryotic microbes remain poorly understood (Seidl MF, Thomma BP, BioEssays 36:335-345, 2014). Ever since the 19th century Irish famine, the oomycete Phytophthora infestans has caused recurrent outbreaks on potato and tomato crops that have been primarily caused by the successive rise and migration of pandemic asexual lineages (Goodwin SB, Cohen BA, Fry WE, Proc Natl Acad Sci USA 91:11591-11595, 1994; Yoshida K, Burbano HA, Krause J, Thines M, Weigel D, Kamoun S, PLoS Pathog 10:e1004028, 2014; Yoshida K, Schuenemann VJ, Cano LM, Pais M, Mishra B, Sharma R, Lanz C, Martin FN, Kamoun S, Krause J, et al.
View Article and Find Full Text PDFIn Hemiptera, presumptive stylets for each consecutive postembryonic instar are manufactured prior to ecdysis to replace the ecdysial stylets discarded with the exuviae. With the discovery that the bacterium "Candidatus" Liberibacter solanacearum accesses the tissues involved in the stylet replacement process of the potato psyllid, a hypothesis was formed that the bacterium could adhere to the stylets of freshly emerged instars and hence gain access to the host plant when feeding is resumed. Although unproven, it was imperative that a model for stylet replacement be built.
View Article and Find Full Text PDFBackground: Oomycetes are a group of filamentous eukaryotic microorganisms that have colonized all terrestrial and oceanic ecosystems, and they include prominent plant pathogens. The Aphanomyces genus is unique in its ability to infect both plant and animal species, and as such exemplifies oomycete versatility in adapting to different hosts and environments. Dissecting the underpinnings of oomycete diversity provides insights into their specificity and pathogenic mechanisms.
View Article and Find Full Text PDFBackground: Intraspecific variation in ploidy occurs in a wide range of species including pathogenic and nonpathogenic eukaryotes such as yeasts and oomycetes. Ploidy can be inferred indirectly - without measuring DNA content - from experiments using next-generation sequencing (NGS). We present nQuire, a statistical framework that distinguishes between diploids, triploids and tetraploids using NGS.
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