86 research outputs found
Management of Root-knot Nematode (Meloidogyne incognita) onPittosporum tobira Under Greenhouse, Field, and On-farm Conditions in Florida
Root-knot nematodes are important pests of cut foliage crops in Florida. Currently, effective nematicides for control of these nematodes on cut foliage crops are lacking. Hence, research was conducted at the University of Florida to identify pesticides or biopesticides that could be used to manage these nematodes. The research comprised on-farm, field, and greenhouse trials. Nematicide treatments evaluated include commercial formulations of spirotetramat, furfural, and Purpureocillium lilacinum (=Paecilomyces lilacinus) strain 251. Treatment applications were made during the spring and fall seasons according to manufacturer's specifications. Efficacy was evaluated based on J2/100 cm3 of soil, J2/g of root, and crop yield (kg/plot). Unlike spirotetramat, which did not demonstrate any measurable effects on Meloidogyne incognita J2 in the soil, furfural and P. lilacinum were marginally effective in reducing the population density of M. incognita on Pittosporum tobira. However, nematode reduction did not affect yield significantly. Although furfural and P. lilacinum have some potential for management of M. incognita on cut foliage crops, their use as a lone management option would likely not provide the needed level of control. Early treatment application following infestation provided greater J2 suppression compared to late application,suggesting the need for growers to avoid infested fields
Vertical Distribution of Pasteuria penetrans Parasitizing Meloidogyne incognita on Pittosporum tobira in Florida
Pasteuria penetrans is considered as the primary agent responsible for soil suppressiveness to root-knot nematodes widely distributed in many agricultural fields. A preliminary survey on a Pittosporum tobira field where the grower had experienced a continuous decline in productivity caused by Meloidogyne incognita showed that the nematode was infected with Pasteuria penetrans. For effective control of the nematode, the bacterium and the host must coexist in the same root zone. The vertical distribution of Pasteuria penetrans and its relationship with the nematode host in the soil was investigated to identify (i) the vertical distribution of P. penetrans endospores in an irrigated P. tobira field and (ii) the relationship among P. penetrans endospore density, M. incognita J2 population density, and host plant root distribution over time. Soil bioassays revealed that endospore density was greater in the upper 18 cm of the top soil compared with the underlying depths. A correlation analysis showed that the endospore density was positively related to the J2 population density and host plant root distribution. Thus, the vertical distribution of P. penetrans was largely dependent on its nematode host which in turn was determined by the distribution of the host plant roots. The Pasteuria was predominant mostly in the upper layers of the soil where their nematode host and the plant host roots are abundant, a factor which may be a critical consideration when using P. penetrans as a nematode biological control agent
Management of Root-knot Nematode (Meloidogyne incognita) onPittosporum tobira Under Greenhouse, Field, and On-farm Conditions in Florida
Combined Report: Aviation Weather Knowledge Assessment & General Aviation (GA) Pilotsâ Interpretation of Weather Products
Prior research has indicated that general aviation (GA) pilots may lack adequate knowledge of aviation weather concepts and skill at interpreting aviation weather displays. Therefore, the purpose of the current project was to develop and validate a comprehensive set of aviation weather knowledge and interpretation multiple-choice questions, and in turn, to use the questions to assess pilot understanding of aviation weather concepts and displays. An interdisciplinary research team that included two meteorologists, one Gold Seal Certificated Flight Instructor (CFI), a human factors psychologist, and several human factors graduate students performed this research
Vertical Distribution of Pasteuria penetrans Parasitizing Meloidogyne incognita on Pittosporum tobira in Florida
Yield of colorectal cancer at colonoscopy according to faecal haemoglobin concentration in symptomatic patients referred from primary care
Background:
Lower gastrointestinal (GI) symptoms are poor predictors of colorectal cancer (CRC). This study examined the diagnostic yield of colonoscopy by faecal haemoglobin concentration (fâHb) in symptomatic patients assessed in primary care by faecal immunochemical testing (FIT).
Methods:
In three Scottish NHS Boards, FIT kits (HMâJACKarc, Hitachi Chemical Diagnostics Systems Co., Ltd, Tokyo, Japan) were used by GPs to guide referrals for patients with lower GI symptoms (lab data studied for 12 months from December 2015 onward in Tayside, 18 months from June 2018 onward in Fife, and 5 months from September 2018 onward in Greater Glasgow and Clyde). CRC cases diagnosed at colonoscopy were ascertained from colonoscopy and pathology records.
Results:
4841 symptomatic patients who underwent colonoscopy after FIT submission were included. Of 2166 patients (44.7%) with fâHb <10 ”g Hb/g faeces (”g/g), 14 (0.6%) were diagnosed with CRC, with a number needed to scope (NNS) of 155. Of 2675 patients (55.3%) with fâHb â„10 ”g/g, 252 were diagnosed with CRC (9.4%) with a NNS of 11. Of 705 patients with fâHb â„400 ”g/g, 158 (22.4%) were diagnosed with CRC with a NNS of 5. Over half of those diagnosed with CRC with fâHb <10 ”g/g had coâexisting anaemia.
Conclusions:
Symptomatic patients with fâHb â„10 ”g/g should undergo further investigation for CRC, while higher fâHb could be used to triage its urgency during the COVIDâ19 recovery phase. Patients with fâHb <10 ”g/g, without anaemia, are very unlikely to be diagnosed with CRC and the majority need no further investigation
Mitochondrial Haplotype-based Identification of Root-knot Nematodes (Meloidogyne spp.) on Cut Foliage Crops in Florida
HpARI protein secreted by a helminth parasite suppresses interleukin-33
Infection by helminth parasites is associated with amelioration of allergic reactivity, but mechanistic insights into this association are lacking. Products secreted by the mouse parasite Heligmosomoides polygyrus suppress type 2 (allergic) immune responses through interference in the interleukin-33 (IL-33) pathway. Here, we identified H. polygyrus Alarmin Release Inhibitor (HpARI), an IL-33-suppressive 26-kDa protein, containing three predicted complement control protein (CCP) modules. In vivo, recombinant HpARI abrogated IL-33, group 2 innate lymphoid cell (ILC2) and eosinophilic responses to Alternaria allergen administration, and diminished eosinophilic responses to Nippostrongylus brasiliensis, increasing parasite burden. HpARI bound directly to both mouse and human IL-33 (in the cytokine's activated state) and also to nuclear DNA via its N-terminal CCP module pair (CCP1/2), tethering active IL-33 within necrotic cells, preventing its release, and forestalling initiation of type 2 allergic responses. Thus, HpARI employs a novel molecular strategy to suppress type 2 immunity in both infection and allergy. Osbourn et al identified HpARI, a protein secreted by a helminth parasite that is capable of suppressing allergic responses. HpARI binds to IL-33 (a critical inducer of allergy) and nuclear DNA, preventing the release of IL-33 from necrotic epithelial cells
Intestinal helminth infection drives carcinogenesis in colitis-associated colon cancer
Inflammatory bowel diseases (IBD) are chronic inflammatory disorders of the
gastrointestinal tract, strongly associated with an increased risk of
colorectal cancer development. Parasitic infections caused by helminths have
been shown to modulate the hostâs immune response by releasing
immunomodulatory molecules and inducing regulatory T cells (Tregs). This
immunosuppressive state provoked in the host has been considered as a novel
and promising approach to treat IBD patients and alleviate acute intestinal
inflammation. On the contrary, specific parasite infections are well known to
be directly linked to carcinogenesis. Whether a helminth infection interferes
with the development of colitis-associated colon cancer (CAC) is not yet
known. In the present study, we demonstrate that the treatment of mice with
the intestinal helminth Heligmosomoides polygyrus at the onset of tumor
progression in a mouse model of CAC does not alter tumor growth and
distribution. In contrast, H. polygyrus infection in the early inflammatory
phase of CAC strengthens the inflammatory response and significantly boosts
tumor development. Here, H. polygyrus infection was accompanied by long-
lasting alterations in the colonic immune cell compartment, with reduced
frequencies of colonic CD8+ effector T cells. Moreover, H. polygyrus infection
in the course of dextran sulfate sodium (DSS) mediated colitis significantly
exacerbates intestinal inflammation by amplifying the release of colonic IL-6
and CXCL1. Thus, our findings indicate that the therapeutic application of
helminths during CAC might have tumor-promoting effects and therefore should
be well-considered
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