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Meloidogyne incognita- and Rotylenchulus reniformis-resistant new cotton cultivars have recently become available, giving growers a new option in nematode management. The objectives of this study were: (i) to determine the yield potential of the new cultivars PHY 360 W3FE (M. incognita-resistant) and PHY 332 W3FE (R. reniformis-resistant) in nematode-infested fields and (ii) to evaluate the effects of combining the nematicides Reklemel (fluazaindolizine), Vydate C-LV (oxamyl), and the seed treatment BIOST Nematicide 100 (heat killed Burkholderia rinojenses and its non-living spent fermentation media) with resistant cotton cultivars on nematode population levels and lint yield. Field experiments in 2020 and 2021 indicated M. incognita population levels were 73% lower on PHY 360 W3FE (R) and 80% lower for R. reniformis on the PHY 332 W3FE (R) at 40 days after planting. Nematode eggs per gram of root were further reduced an average of 86% after the addition of Reklemel and Vydate C-LV when averaging both cultivars over the two years. Tests with BIOST Nematicide 100 + Reklemel + Vydate C-LV (0.56 + 2.5 L/ha) in both M. incognita and R. reniformis fields produced higher lint yields. Overall, planting PHY 360 W3FE (R) and PHY 332 W3FE (R) improved yields an average of 364 kg/ha while limiting nematode population increases. The addition of the nematicides further increased yields 152 kg/ha of the nematode-resistant cultivars.

Plant parasitic nematodes are major pests on upland cotton worldwide and in the United States. The reniform nematode, Rotylenchulus reniformis and the southern root-knot nematode Meloidogyne incognita are some of the most damaging nematodes on cotton in the United States. Current management strategies focus on reducing nematode populations with nematicides. The objective of this research was to integrate additional fertilizer and nematicide combinations into current practices to establish economical nematode management strategies while promoting cotton yield and profit. Microplot and field trials were run to evaluate fertilizer and nematicide combinations applied at the pinhead square (PHS) and first bloom (FB) plant growth stages to reduce nematode population density and promote plant growth and yield. Cost efficiency was evaluated based on profit from lint yields and chemical input costs. Data combined from 2019 and 2020 suggested a nematicide seed treatment (ST) ST + (NH4)2SO4 + Vydate® C-LV + Max-In® Sulfur was the most effective in increasing seed cotton yields in the R. reniformis microplot trials. In R. reniformis field trials, a nematicide ST + (NH4)2SO4 + Vydate® C-LV at PHS supported the largest lint yield and profit per hectare at $1176. In M. incognita field trials, a nematicide ST + 28-0-0-5 + Vydate® C-LV + Max-In® Sulfur at PHS and FB supported the largest lint yields and profit per hectare at $784. These results suggest that combinations utilizing fertilizers and nematicides applied together across the season in addition to current fertility management show potential to promote yield and profit in R. reniformis and M. incognita infested cotton fields.

Plant parasitic nematodes (PPN) are microscopic soil herbivores that cause damage to many economic crops. For the last century, it has been proposed that chemotaxis is the primary means by which PPN locate host plant roots. The identities and modes of action of chemoattractants that deliver host-specific messages to PPN, however, are still elusive. In this study, a unique multidimensional agar-based motility assay was developed to assess the impacts of root exudates on the short-range motility and orientation of PPN. Three PPN (Rotylenchulus reniformis, Meloidogyne incognita and Heterodera glycines) and root exudates from their respective host and non-host plants (cotton, soybean, and peanut) were used to validate the assay. As predicted, R. reniformis and M. incognita were attracted to root exudates of cotton and soybean (hosts), but not to the exudates of peanut (non-host). Likewise, H. glycines was attracted to soybean (host) root exudates. These results underpinned the intrinsic roles of root exudates in conveying the host specificity of PPN. In particular, PPN selectively identified and targeted to hydrophilic, but not hydrophobic, fractions of root exudates, indicating that groundwater should be an effective matrix for chemotaxis associated with PPN and their host plant interactions.

The goal of this research is to determine the mechanism of action of two Bacillus spp. that can manage Meloidogyne incognita population density in cotton. The overall objectives are 1) determine the efficacy and direct antagonistic capabilities of the Bacillus spp. and 2) determine the systemic capabilities of the Bacillus spp. The greenhouse in planta assay indicated B. amyloliquefaciens QST713 and B. firmus I-1582 could manage M. incognita similarly to the chemical standard fluopyram. An in vitro assay determined that B. firmus I-1582 and its extracted metabolites were able to directly manage M. incognita second stage juveniles by increasing mortality rate above 75%. A split root assay, used to determine systemic capabilities of the bacteria, indicated B. amyloliquefaciens QST713 and B. firmus I-1582 could indirectly decrease the nematode population density. Another species, B. mojavensis strain 2, also demonstrated systemic capabilities but was not a successful biological control agent because it supported a high population density in greenhouse in planta assay and in the split root assay. A RT-qPCR assay was used to confirm any systemic activity observed in the split root assay. At 24 hours both B. amyloliquefaciens QST713 and B. firmus I-1582 upregulated one gene involved in the initial stages of JA synthesis pathway but not another gene involved in the later stages of JA synthesis. These results point to a JA intermediate molecule, most likely OPDA, stimulated by the bacteria rather than JA in a short-term systemic response. After 1 week, the Bacillus spp. stimulated a SA-responsive defense related gene. The long-term systemic response to the Bacillus spp. indicates salicylic acid also plays a role in defense conferred by these bacteria. The final assay was a qPCR to determine the concentration of the bacteria on the cotton roots after 24 days. Bacillus amyloliquefaciens QST713 and B. firmus I-43 1582 were able to colonize the root successfully, with the concentration after 24 days not significantly differing from the concentration at inoculation. This study identifies two bacteria that work via systemic resistance and will help aid in implementing these species in an integrated management system. [ABSTRACT FROM AUTHOR]

The endomembrane system, functioning in secretion, performs many roles relating to eukaryotic cell physiological processes and the Golgi apparatus is the central organelle in this system. An essential associated Golgi component is the conserved oligomeric Golgi (COG) complex, maintaining correct Golgi structure and function during retrograde trafficking. In animals, naturally occurring cog mutants provide a window into understanding it's function(s). Eliminating even one COG component impairs its function. In animals, COG mutations lead to severe cell biological and developmental defects and death while far less is understood in plants which is changing. The plant genetic model Arabidopsis thaliana COG complex functions in growth, cell expansion and other processes, involving direct interactions with other secretion system components including the exocyst, soluble N-Ethylmaleimide-Sensitive Factor Attachment Protein Receptor (SNARE), and the microtubule cytoskeleton. Recent experiments have identified a defense role for the COG complex in plants, the focus of this review. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium spp.) is attacked by parasitic nematodes including the reniform nematode (Rotylenchulus reniformis Linford and Oliveira). Options for management of reniform nematode are limited. No cultivars of upland cotton (G. hirsutum L.) have genetic resistance. Our objectives were to evaluate the USDA G. hirsutum collection for reaction to parasitism by R. reniformis, and determine the value of measurement of eggs (reproduction) or vermiform stages (nematode survival) as an indicator of nematode resistance. In groups of 50, accessions were evaluated in the greenhouse, using single plants in four replicates. Accessions were planted in sterile soil and inoclated with a mixture of R. reniformis isolates. After 60 d, soil populations of vermiform nematodes were determined, and eggs were extracted from the root system and counted. Paymaster 'PM 1218' was included as a check in every experiment. Out of 1973 accessions with at least one replication, none showed high levels of resistance. Seven accessions had lower population development than PM 1218 after repeated evaluations. Results indicated egg counts and vermiform counts were correlated, but not closely. Egg counts were higher and more variable than vermiform counts. While some accessions showed levels of resistance that might be useful in cotton improvement, evaluation remains difficult and introgression of genes for reniform nematode resistance remains a long-term breeding objective.

Objective. Solid organ transplant recipients are at increased risk for invasive pneumococcal disease. The American Academy of Pediatrics recommends immunization with sequential pneumococcal vaccines for this group; however, data are lacking. Accordingly, this study was designed to evaluate the safety and immunogenicity of the recommended regimen. Methods. Pediatric solid organ transplant recipients (n = 25) between 2 and 18 years of age who had not previously received 7-valent conjugate pneumococcal vaccine (PCV7) were enrolled. These patients received 2 doses of the PCV7 and a single dose of the 23-valent polysaccharide pneumococcal vaccine (23V). Each vaccine dose was given 2 months apart. Healthy age-matched controls (n = 23) were enrolled for comparison. Controls received a single dose of PCV7 followed 2 months later by a single dose of 23V. Antibody concentrations to serotypes 1, 4, 5, 6B, 9V, 14, 18C, 19F, and 23F were measured by enzyme-linked immunosorbent assay prevaccination, 2 months after each vaccine dose and 5 to 7 months after 23V. Local and systemic reactions to each vaccine dose were recorded. Results. Systemic and injection-site reactions were comparable between the 2 groups. Significant rises in serotype-specific pneumococcal antibody geometric mean concentrations from prevaccination levels were observed in both groups; however, final antibody responses to serotypes 1, 4, 9V, 14, 18C, 19F, and 23F were significantly lower in solid organ transplant recipients compared with the control group. Antibody concentrations did not increase significantly among solid organ transplant patients after the second dose of PCV7. No additional increase in PCV7-associated serotype-specific antibody levels was observed after the 23V dose in both groups. Heart transplant recipients had lower antibody responses compared with liver transplant recipients. Conclusions. Although the pneumococcal vaccine regimen was safe and immunogenic among pediatric solid organ transplant recipients, the patients did not seem to benefit from the second dose of PCV7 or from the 23V dose given 2 months later. Additional studies are needed to determine the number of PCV7 doses and the interval between PCV7 and 23V to induce optimal responses. Pediatrics 2005;116:160-167; solid organ transplant recipient, invasive pneumococcal disease, conjugate pneumococcal vaccine, vaccine response. ABBREVIATIONS. AAP, American Academy of Pediatrics; PCV7, 7-valent conjugate pneumococcal vaccine; 23V, 23-valent polysaccharide pneumococcal vaccine; PTLD, posttransplant lymphoproliferative disease; GMC, geometric mean antibody concentration., Solid organ transplant recipients are at increased risk of bacterial infections including invasive pneumococcal infections. (1-4) This has also been shown in pediatric solid organ transplant recipients, (5,6) who (like [...]

Glycine max root cells developing into syncytia through the parasitic activities of the pathogenic nematode Heterodera glycines underwent isolation by laser microdissection (LM). Microarray analyses have identified the expression of a G. max DOESN'T MAKE INFECTIONS3 (DMI3) homolog in syncytia undergoing parasitism but during a defense response. DMI3 encodes part of the common symbiosis pathway (CSP) involving DMI1, DMI2 , and other CSP genes. The identified DMI gene expression, and symbiosis role, suggests the possible existence of commonalities between symbiosis and defense. G. max has 3 DMI1 , 12 DMI2 , and 2 DMI3 paralogs. LM-assisted gene expression experiments of isolated syncytia under further examination here show G. max DMI1-3, DMI2-7 , and DMI3-2 expression occurring during the defense response in the H. glycines -resistant genotypes G. max [Peking/PI548402] and G. max [PI88788] indicating a broad and consistent level of expression of the genes. Transgenic overexpression (OE) of G. max DMI1-3, DMI2-7 , and DMI3-2 impairs H. glycines parasitism. RNA interference (RNAi) of G. max DMI1-3, DMI2-7 , and DMI3-2 increases H. glycines parasitism. The combined opposite outcomes reveal a defense function for these genes. Prior functional transgenic analyses of the 32-member G. max mitogen activated protein kinase (MAPK) gene family has determined that 9 of them act in the defense response to H. glycines parasitism, referred to as defense MAPK s. RNA-seq analyses of root RNA isolated from the 9 G. max defense MAPK s undergoing OE or RNAi reveal they alter the relative transcript abundances (RTAs) of specific DMI1, DMI2 , and DMI3 paralogs. In contrast, transgenically-manipulated DMI1-3, DMI2-7 , and DMI3-2 expression influences MAPK3-1 and MAPK3-2 RTAs under certain circumstances. The results show G. max homologs of the CSP, and defense pathway are linked, apparently involving co-regulated gene expression. [ABSTRACT FROM AUTHOR]

The conserved oligomeric Golgi (COG) complex maintains correct Golgi structure and function during retrograde trafficking. Glycine max has 2 paralogs of each COG gene, with one paralog of each gene family having a defense function to the parasitic nematode Heterodera glycines. Experiments presented here show G. max COG paralogs functioning in defense are expressed specifically in the root cells (syncytia) undergoing the defense response. The expressed defense COG gene COG7-2-b is an alternate splice variant, indicating specific COG variants are important to defense. Transcriptomic experiments examining RNA isolated from COG overexpressing and RNAi roots show some COG genes co-regulate the expression of other COG complex genes. Examining signaling events responsible for COG expression, transcriptomic experiments probing MAPK overexpressing roots show their expression influences the relative transcript abundance of COG genes as compared to controls. COG complex paralogs are shown to be found in plants that are agriculturally relevant on a world-wide scale including Manihot esculenta, Zea mays, Oryza sativa, Triticum aestivum, Hordeum vulgare, Sorghum bicolor, Brassica rapa, Elaes guineensis and Saccharum officinalis and in additional crops significant to U.S. agriculture including Beta vulgaris, Solanum tuberosum, Solanum lycopersicum and Gossypium hirsutum. The analyses provide basic information on COG complex biology, including the coregulation of some COG genes and that MAPKs functioning in defense influence their expression. Furthermore, it appears in G. max and likely other crops that some level of neofunctionalization of the duplicated genes is occurring. The analysis has identified important avenues for future research broadly in plants. [ABSTRACT FROM AUTHOR]

The conserved oligomeric Golgi (COG) complex, functioning in retrograde trafficking, is a universal structure present among eukaryotes that maintains the correct Golgi structure and function. The COG complex is composed of eight subunits coalescing into two sub-complexes. COGs1–4 compose Sub-complex A. COGs5–8 compose Sub-complex B. The observation that COG interacts with the syntaxins, suppressors of the erd2-deletion 5 (Sed5p), is noteworthy because Sed5p also interacts with Sec17p [alpha soluble NSF attachment protein (α-SNAP)]. The α-SNAP gene is located within the major Heterodera glycines [soybean cyst nematode (SCN)] resistance locus (rhg1) and functions in resistance. The study presented here provides a functional analysis of the Glycine max COG complex. The analysis has identified two paralogs of each COG gene. Functional transgenic studies demonstrate at least one paralog of each COG gene family functions in G. max during H. glycines resistance. Furthermore, treatment of G. max with the bacterial effector harpin, known to function in effector triggered immunity (ETI), leads to the induced transcription of at least one member of each COG gene family that has a role in H. glycines resistance. In some instances, altered COG gene expression changes the relative transcript abundance of syntaxin 31. These results indicate that the G. max COG complex functions through processes involving ETI leading to H. glycines resistance. [ABSTRACT FROM AUTHOR]

Plant parasitic nematodes (PPN) are microscopic soil herbivores that cause damage to many economic crops. For the last century, it has been proposed that chemotaxis is the primary means by which PPN locate host plant roots. The identities and modes of action of chemoattractants that deliver host-specific messages to PPN, however, are still elusive. In this study, a unique multidimensional agar-based motility assay was developed to assess the impacts of root exudates on the short-range motility and orientation of PPN. Three PPN (Rotylenchulus reniformis, Meloidogyne incognita and Heterodera glycines) and root exudates from their respective host and non-host plants (cotton, soybean, and peanut) were used to validate the assay. As predicted, R. reniformis and M. incognita were attracted to root exudates of cotton and soybean (hosts), but not to the exudates of peanut (non-host). Likewise, H. glycines was attracted to soybean (host) root exudates. These results underpinned the intrinsic roles of root exudates in conveying the host specificity of PPN. In particular, PPN selectively identified and targeted to hydrophilic, but not hydrophobic, fractions of root exudates, indicating that groundwater should be an effective matrix for chemotaxis associated with PPN and their host plant interactions. [ABSTRACT FROM AUTHOR]

Abstract: Over the past decade, we have seen an increasing market for biopesticides and an increase in number of microbial control studies directed towards plant‐parasitic nematodes. This literature survey provides an overview of research on biological control of two economically important plant‐parasitic nematodes, Meloidogyne incognita (Kofoid & White) Chitwood (southern root‐knot nematode) and Heterodera glycines Ichinohe (soybean cyst nematode) using spore‐forming plant growth‐promoting rhizobacteria (PGPR). In this review, the current biological control strategies for the management of those cotton and soybean nematodes, the mechanism of using BacillusPGPR for biological control of plant‐parasitic nematode including induced systemic resistance and antagonism and the future of biological control agents on management of plant‐parasitic nematodes are covered. [ABSTRACT FROM AUTHOR]

Heterodera glycines, the soybean cyst nematode, is the most economically important plant-parasitic nematode on soybean production in the U.S. The objectives of this study were to evaluate the potential of plant growth-promoting rhizobacteria (PGPR) strains for mortality of H. glycines J2 in vitro and for reducing nematode population density on soybean in greenhouse, microplot, and field trials. The major group causing mortality to H. glycines in vitro was the genus Bacillus that consisted of 92.6% of the total 663 PGPR strains evaluated. The subsequent greenhouse, microplot, and field trials indicated that B. velezensis strain Bve2 consistently reduced H. glycines cyst population density at 60 DAP. Bacillus mojavensis strain Bmo3 suppressed H. glycines cyst and total H. glycines population density under greenhouse conditions. Bacillus safensis strain Bsa27 and Mixture 1 (Bve2 + Bal13) reduced H. glycines cyst population density at 60 DAP in the field trials. Bacillus subtilis subsp. subtilis strains Bsssu2 and Bsssu3, and B. velezensis strain Bve12 increased early soybean growth including plant height and plant biomass in the greenhouse trials. Bacillus altitudinis strain Bal13 increased early plant growth on soybean in the greenhouse and microplot trials. Mixture 2 (Abamectin + Bve2 + Bal13) increased early plant growth in the microplot trials at 60 DAP, and also enhanced soybean yield at harvest in the field trials. These results demonstrated that individual PGPR strains and mixtures can reduce H. glycines population density in the greenhouse, microplot, and field conditions, and increased yield of soybean. [ABSTRACT FROM AUTHOR]

In the past decade, increased attention has been placed on biological control of plar.t-parasitic nematodes using various fungi and bacteria. The objectives of this study were to evaluate the potential of 662 plant growth-promoting rhizobacteria (PGPR) strains for mortality to Meloidogyne incognita J2 in vitro and for nematode management in greenhouse, microplot, and field trials. Results indicated that the mortality of M. incognita J2 by the PGPR strains ranged from 0 to 100% with an average of 39%. Among the PGPR strains examined, 212 of 662 strains (or 33%) caused significantly greater mortality percent of M. incognita J2 than the untreated control. Bacillus was the major genus initiating a greater mortality percentage when compared with the other genera. In subsequent trials, B. velezensis strain Bve2 reduced M. incognita eggs per gram of cotton root in the greenhouse trials at 45 days after planting (DAP) similarly to the commercial standards Abamectin and Clothianidin plus B.firmus 1-1582. Bacillus mojavensis strain Bmo3, B. velezensis strain Bve2, B. subtilis subsp. subtilis strain Bsssu3, and the Mixture 2 (Abamectin + Bve2 + B. altitudinis strain Ball 3) suppressed M. incognita eggs per gram of root in the microplot at 45 DAP. Bacillus velezensis strains Bve2 and Bvel2 also increased seed-cotton yield in the microplot and field trials. Overall, results indicate that B. velezensis strains Bve2 and Bvel2, B. mojavensis strain Bmo3, and Mixture 2 have potential to reduce M. incognita population density and to enhance growth of cotton when applied as in-furrow sprays at planting. [ABSTRACT FROM AUTHOR]

Greenhouse experiments were conducted to determine the effects of nitrogen (N), phosphorus (P), and potassium (K) fertilizer on biomass yield and flavonoid content of American skullcap (Scutellaria lateriflora). Each experiment was carried out two times and consisted of six levels of each nutrient. The regressions gave maxima for dry matter, baicalein yield, and chrysin yield at 446, 412, and 351 kg N/ha for N fertilizer, respectively. Dry matter yield exhibited linear response to P application. The yield of scutellarein, baicalin, baicalein, and chrysin increased with addition of P. The regression gave maximum for dry matter at 208 kg K/ha for K fertilizer. A linear response to K fertilization was observed for scutellarein concentration. P application had the greatest effect on the flavonoids analyzed, whereas K had least, which may be attributed in part to the presence of K in the fritted clay medium. [ABSTRACT FROM AUTHOR]

Heterodera glycines (Soybean Cyst nematode, or SCN) and Meloidogyne incognita (Root-Knot nematode, or RKN) are two damaging plant-parasitic nematodes on important field crops. Developing a quick method to distinguish between live and dead SCN and RKN second stage juveniles (J2) is vital for high throughput screening of pesticides or biological compounds against SCN and RKN. The in vitro assays were conducted in 96-well plates to determine the optimum chemical stimulus to distinguish between live and dead SCN and RKN J2. Sodium carbonate (Na2CO3), sodium bicarbonate (NaHCO3), and sodium hydroxide (NaOH) were evaluated for the nematode response to see if these compounds can help distinguish between viable from the dead J2. Results indicated that live SCN J2 responded equally (P ≤ 0.05) to 1 μl Na2CO3 and 10 μl NaHCO3 in 100 μl of water at pH = 10. Live SCN J2 responded by twisting their bodies in a curling shape and increasing rate of movements within 2 minutes of exposure. The twisting activity continued for up to 30 minutes. Live RKN J2 responded by increasing activity with the application of 1 μl NaOH in 100 μl of water at pH = 10 also in the 2 minutes to 30 minutes time frame. Furthermore, in growth chamber tests to confirm the infectivity of live SCN. The live SCN as determined by exposure to 1 μl of Na2CO3 indicated 60.5% of the SCN J2 were alive and of those, 29.5% were infective and entered the soybean roots. The 1 μl of NaOH stimulus revealed that 75.2% RKN J2 were alive and of those, 14.9% were infective and entered soybean roots. These results confirmed that 1 μl of Na2CO3 added to 100 μl suspension of SCN J2 and 1 μl of NaOH added to 100 μl suspension of RKN J2 are the effective stimuli for rapidly distinguishing between live and dead SCN and RKN J2 in vitro. SCN and RKN J2 responded differently to different compounds. [ABSTRACT FROM AUTHOR]

Aims Nitrogen (N) fertilization and lime addition may affect soil microbial and nematode communities and ecosystem functions through changing environmental conditions, such as soil pH and soil organic carbon. The objectives of this experiment were to examine the impact of N input and liming on soil microbial and nematode communities and to identify the key environmental determinant of community composition in a century-old fertilization and crop rotation experiment. Methods The field experiment consisting of a 3-year crop rotation regime was established in 1911 in southeastern usa. Four treatments, (i) no-input control, (ii) NPK with winter legume, (iii) PK with legume and lime and (iv) NPK with legume and lime, were included in this study. soil samples collected at the 0-5 cm depth were used to determine the bacterial growth rate by the³H-thymidine incorporation technique. Incorporation of 13C into neutral lipids, glycolipids and phospholipid fatty acids (PlFas) was measured after incubation of soil with 13C-labeled acetate for 24 h. Freeliving nematodes in fresh soil were extracted using a density sucrose centrifugal flotation method and identified to trophic group level. Important Findings liming resulted in a 10-fold increase in bacterial growth rates compared with the no-input control, whereas N fertilization had no significant effect. multivariate analysis of PlFa profiles showed that soil microbial community composition was different among the four treatments; the difference was primarily driven by soil pH. PlFas indicative of gram-negative bacteria covaried with soil pH, but not those of fungi and actinobacteria. liming enhanced 13C incorporation into neutral lipids, glycolipids and phospholipids by 2-15 times. In addition, 13C incorporation into 16:0, 16:1ω9, 18:1ω9, 18:1ω7 and 18:2ω6 were greater than other PlFas, suggesting that gramnegative bacteria and fungi were more active and sensitive to simple C input. bacterivorous nematodes were the dominant trophic group in the soil, but no significant differences in nematode communities were found among the treatments. our results suggest that soil pH had a greater impact than N fertilization on soil microbial community composition and activity in a crop rotation system including legumes. [ABSTRACT FROM AUTHOR]

Reniform nematode is a semi-endoparasitic nematode species causing significant yield loss in numerous crops, including cotton (Gossypium hirsutum L.). An RNA-sequencing analysis was conducted to measure transcript abundance in reniform nematode susceptible (DP90 & SG747), resistant (BARBREN-713), and hypersensitive (LONREN-1) genotypes of cotton (Gossypium hirsutum L.) with and without reniform nematode infestation. Over 90 million trimmed high quality reads were assembled into 84,711 and 80, 353 transcripts using the G. arboreum and the G. raimondii genomes as references. Many transcripts were significantly differentially expressed between the three different genotypes both prior to and during nematode pathogenesis, including transcripts corresponding to the gene ontology categories of cell wall, hormone metabolism and signaling, redox reactions, secondary metabolism, transcriptional regulation, stress responses, and signaling. Further analysis revealed that a number of these differentially expressed transcripts mapped to the G. raimondii and/or the G. arboreum genomes within 1 megabase of quantitative trait loci that had previously been linked to reniform nematode resistance. Several resistance genes encoding proteins known to be strongly linked to pathogen perception and resistance, including LRR-like and NBS-LRR domain-containing proteins, were among the differentially expressed transcripts mapping near these quantitative trait loci. Further investigation is required to confirm a role for these transcripts in reniform nematode susceptibility, hypersensitivity, and/or resistance. This study presents the first systemic investigation of reniform nematode resistance-associated genes using different genotypes of cotton. The candidate reniform nematode resistance-associated genes identified in this study can serve as the basis for further functional analysis and aid in further development of reniform a nematode resistant cotton germplasm. [ABSTRACT FROM AUTHOR]

Fusarium wilt is an important and widespread disease of cotton (Gossypium hirsutum L. and Gossypium barbadense L.) caused by several races and genotypes of Fusarium oxysporum f. sp. vasinfectum W.C. Snyder & H.N. Hans (FOV). A two-year survey (2012-2013) was conducted to assess the distribution of the fungus, and in particular FOV race 4, throughout the United States (U.S.) Cotton Belt. Partial sequences of the translation elongation factor (EF-1a) region of FOV cultured from symptomatic cotton plants were compared to a database of sequences of known genotypes. Five nominal races of FOV, races 1, 2, 3, 4, and 8, and four previously recognized southeastern genotypes, LA108, LA110, LA112, and LA127/140, were identified. Representative isolates of each were pathogenic on cotton in greenhouse assays. A unique genotype of FOV, MDS-12, which was characterized with additional sequencing of the phosphate permease-like protein, ß-tubulin, and intergenic spacer regions, was identified in Alabama, Arkansas, Mississippi, Louisiana, and Georgia. FOV race 4 was not detected outside of California. [ABSTRACT FROM AUTHOR]

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A field experiment was conducted in Alabama to determine the effect of timing and frequency of harvest on shoot yield and flavonoid content of American skullcap. In the first year (2008), harvesting twice gave 36% higher yield than harvesting once. In the second year (2009), plant die-off late in the season prevented a comparison of two and three harvests, so only the effects of early and late harvest were compared. There was no difference in yield between early or late harvesting. Plant height and density, percent dry matter, and shoot yield were higher in the first harvest than the second harvest. In 2008, the yield and concentration of flavonoid baicalein was the highest. In 2009, the yield and concentration of baicalin was the highest, followed by baicalein and apigenin. There were no differences in flavonoid yield between early and late harvest. Flavonoid yield in 2009 was 58% higher in the first harvest than in the second. [ABSTRACT FROM AUTHOR]

Due to increased restrictions on the use of chemical nematicides, alter-native nematode management strategies, including biocontrol, are needed. The objectives of this study were to evaluate the potential of Bacillus firmus GB-126 and Paecilomyces lilacinus 251 in commercial formulations applied separately or concomitantly to manage Rotylen-chulus reniformis in cotton grown under greenhouse, microplot, and field conditions. In the greenhouse, seed treated with B. firmus (1.4 x 107 CFU/seed), an application of P. lilacinus (0.3% vol/vol of water), or the combination of B. firmus and P. lilacinus reduced the number of females, eggs, and vermiforms of R. reniformis (P < 0.02) and in-creased populations of free-living nematodes (P < 0.01). In microplots and field conditions, populations of R. reniformis vermiforms de-creased when exposed to B. firmus and P. lilacinus biocontrol agents at midseason (P < 0.04). Furthermore, stem diameter and free-living nematode numbers increased (P < 0.01) with the combination of B. firmus and P. lilacinus. In the field, numbers of females, eggs, and vermiform life stages at the end of the growing season decreased in the presence of the biocontrol agents applied individually or concomitantly (P < 0.01). Cotton yields from the application of B. firmus GB-126 and P. lilacinus 251 were similar to those from aldicarb, the chemical nematicide standard. [ABSTRACT FROM AUTHOR]

Upland cotton, Gossypium hirsutum L., is highly susceptible to infection by reniform nematode (Rotylenchulus reniformis), which can cause over 10% reduction of cotton yields in Alabama. Detection of reniform nematode (RN) and analysis for molecular variation within its population is important for understanding its interactions with cotton and other host plant species. Restriction analysis of PCR products of ITS1 regions was achieved using four restriction enzymes, HaeIII, HhaI, MspI, and RsaI. These showed similar banding patterns for both male and female populations. However, MspI digestion of ITS1 amplification products showed variants within the combined sex and location effects primarily attributed to a 500 bp fragment that was absent in other restriction digestions. Intra-nematodal variations in 18S and ITS1 rDNA were studied in detail by sequencing a minimum of ten clones in each individual male and female RN isolates in both directions. Multiple sequence alignment of the 18S rDNA sequences showed two major types of sequences within this gene for both male and female RN clones, which could be distinguished at 27 specific sites. Two distinct ITS1 fragments of lengths (550 bp and 720 bp) were observed; referred to as ITS1S and ITS1L respectively. Neighbor-joining analysis was used in revealing the relationships and grouping characteristics between male and female RN clones, with clones grouping together irrespective of sex and isolate. Sequencing of one-third of the 18S and ITS1 rDNA regions provided clear evidence of intra-and inter-nematode variability, in addition to gene conversion events in the 18S rDNA of individual male and female RN clones. [ABSTRACT FROM AUTHOR]

Cotton (Gossypium spp.) is attacked by several species of parasitic nematodes including the reniform nematode (Rotylenchulus reniformis Linford and Oliveria). Qualitative resistance (gene symbol RENlon) was discovered in a wild cotton relative (Gossypium longicalyx J. B. Hutch. & B. J. S. Lee), transferred to an upland (Gossypium hirsutum L.) background, and released as two sister germplasm lines, LONREN-1 and LONREN- 2. In 2010 and 2011, we tested 20 homogeneous resistant and 20 homogeneous susceptible F2:4 and F2:5 lines from the cross LONREN-1 × Fibermax 966 in two fields, one infested with reniform nematode and one not infested. The objective was to determine the effect of RENlon on cotton yield, agronomic traits, and fiber quality in a nematode-infested and a nematode-free environment. Lines with RENlon were stunted during early season growth and yielded less than did their sister lines null for RENlon in the nematode-infested field. At-harvest nematode populations were reduced in plots where lines with RENlon were planted. There were no yield differences between lines with and without RENlon in the nematode-free field. Fiber quality was affected by RENlon, with lines carrying the gene tending to have greater fiber strength, better length uniformity, and lower short fiber content. The RENlon gene is effective in reducing nematode populations and may improve fiber quality; however, the LONREN-1 progenies did not reduce yield losses from reniform nematodes. [ABSTRACT FROM AUTHOR]

Context--Characteristic adolescent risk-taking behavior, including nonadherence with prescribed medications, can be life-threatening for transplant recipients. Suggestions for managing nonadherence in teen recipients include providing them and their parents with adequate information about medications, talking with and listening to pediatric recipients about problems with the comprehensive regimen, and encouraging age-appropriate responsibility for maintaining health. Objective--The clinical goal of this project was to develop a structured age-appropriate educational program to prepare pediatric transplant recipients and their families for the patient's life as a responsible, independent individual. Our primary research goal was to assess patients' and parents' knowledge about critical aspects of heart transplantation and the treatment regimen with brief questionnaires before and after they received the educational materials from their primary nurse coordinator. Design, Setting, Participants--This descriptive pre-post test study was done to assess the effectiveness of an innovative family-centered educational program among 20 pediatric heart transplant recipients and their parents at Children's Hospital of Pittsburgh, University of Pittsburgh Medical Center. Main Outcome Measure, Results--Percentage change in children's scores on questionnaires given before and after the educational intervention ranged from -8% to 300% (mean, 64.1%). Percentage change in scores from before to after for parents ranged from -19% to 53.8% (mean, 7.2%). [ABSTRACT FROM AUTHOR]

Plant-parasitic nematodes (PPN) are among the most economically and ecologically damaging pests, causing severe losses of crop production worldwide. Chemical-based nematicides have been widely used, but these may have adverse effects on human health and the environment. Hence, biological control agents (BCAs) have become an alternative option for controlling PPN, since they are environmentally friendly and cost effective. Lately, a major effort has been made to evaluate the potential of a commercial grade strain of plant growth-promoting rhizobacteria (PGPR) as BCAs, because emerging evidence has shown that PGPR can reduce PPN in infested plants through direct and/or indirect antagonistic mechanisms. Direct antagonism occurs by predation, release of antinematicidal metabolites and semiochemicals, competition for nutrients, and niche exclusion. However, the results of direct antagonism may be inconsistent due to unknown endogenous and exogenous factors that may prevent PGPR from colonizing plant's roots. On the other hand, indirect antagonism may occur from the induced systemic resistance (ISR) that primes whole plants to better fight against various biotic and abiotic constraints, actuating faster and/or stronger defense responses (adaption), enhancing their promise as BCAs. Hence, this review will briefly revisit (i) two modes of PGPR in managing PPN, and (ii) the current working models and many benefits of ISR, in the aim of reassessing current progresses and future directions for isolating more effective BCAs and/or developing better PPN management strategy. [ABSTRACT FROM AUTHOR]

The United States is the third largest producer of cotton and the largest exporter of cotton globally. Fusarium wilt, caused by the soilborne fungal pathogen Fusarium oxysporum f. sp. vasinfectum (Fov), was estimated to cause a $21 million cotton yield loss in 2022. Historically, Alabama was an important producer of cotton in the Southeastern United States and was the first state in which Fusarium wilt on cotton was described. To assess the genetic diversity of Fov field isolates in Alabama, 118 field isolates were collected from six counties across the state from 2014 to 2016. Phylogenetic analysis using TEF1 and RPB2 placed the Fov field isolates into 18 haplotypes. Upon profiling the Tfol transposon insertion in the NAT gene, it was determined that no race 4 isolates were recovered in Alabama. Representatives of all field isolate haplotypes caused disease on Upland cotton variety Rowden in a hydroponic test tube assay. Two haplotype A isolates were the most aggressive isolates recovered, and haplotype A isolate TF1 was more aggressive than the race 4 isolate 89-1A on Upland cotton and had similar symptom severity on Pima cotton. Karyotype profiling indicted an abundance of small chromosomes characteristic of karyotypes that include accessory chromosomes, with considerable variability between isolates. Collectively, our study indicates that Fov isolates from Alabama are genetically diverse, which may have been promoted by its persistence in cotton fields. [ABSTRACT FROM AUTHOR]