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Journal of Nematology Jun 2017The following work was initiated to determine the scope of application methodology and fumigant combinations for increasing efficacy of 1,3-dichloropropene (1,3-D) and...
The following work was initiated to determine the scope of application methodology and fumigant combinations for increasing efficacy of 1,3-dichloropropene (1,3-D) and metam sodium for management of root-knot nematodes ( spp.) in Florida. A series of five experiments were set up during spring and fall seasons to evaluate the potential of different fumigants, alone or in combination, in polyethylene film tomato production. The most promising chemical alternatives to methyl bromide, in terms of root-knot nematode management, were the combinations 1,3-D-chloropicrin, chloropicrin-proprietary solvent ,and 1,3-D-metam sodium. Sprayed or injected metam sodium generally provided only short-term nematode management and by harvest nematode infection was not different from the nontreated control. Drip-applied metam sodium gave good nematode management under high nematode pressure, but needs further verification to establish (i) the importance of soil moisture and temperature on treatment efficacy and (ii) whether similar management can be obtained with fewer than three drip tubes. Broadcast applications of 1,3-D showed better efficacy as compared to applications on a preformed raised bed. Fumigation did not increase tomato yields in spring when root-knot nematode pressure was low, but during fall all chemical treatments increased yields three to five-fold, as root-knot nematode was a major yield-limiting factor.
PubMed: 28706313
DOI: 10.21307/jofnem-2017-058 -
Phytopathology Feb 2018Plant pathogens migrate to new regions through human activities such as trade, where they may establish themselves and cause disease on agriculturally important crops.... (Review)
Review
Plant pathogens migrate to new regions through human activities such as trade, where they may establish themselves and cause disease on agriculturally important crops. Verticillium wilt of lettuce, caused by Verticillium dahliae, is a soilborne fungus that was introduced to coastal California via infested spinach seeds. It has caused significant losses for lettuce growers. Once introduced, Verticillium wilt could be managed by fumigating with methyl bromide and chloropicrin, but this option is no longer available. Growers can also manage the disease by planting broccoli or not planting spinach. These control options require long-term investments for future gain. Verticillium wilt can also be prevented or controlled by testing and providing spinach seeds with little or no V. dahliae infestation. However, seed companies have been reluctant to test or clean spinach seeds, as spinach crops are not affected by Verticillium wilt. Thus, available control options are affected by externalities. Renters and other producers with short time horizons will not undertake long-term investments and seed companies do not take into account the effect of their decision not to test on lettuce producers. We review the literature on the economics of managing crop disease; discuss the economics of managing Verticillium wilt; and review the recent research on the externalities that arise with short-term growers, and between seed companies and growers due to Verticillium wilt. An externality arises whenever the actions of one individual or firm affects the payoffs to another individual or firm not involved in a specific transaction. These externalities have important implications for the management of Verticillium wilt and, more broadly, for the management of migratory pathogens and the diseases they cause in agriculture in general. This review is of interest to policy-makers, the producers, marketers, seed companies, and researchers.
Topics: Agriculture; California; Lactuca; Plant Diseases; Seeds; Spinacia oleracea; Verticillium
PubMed: 28703041
DOI: 10.1094/PHYTO-03-17-0083-RVW -
Environmental Research Oct 2017Our objective was to examine the relationship between residential proximity to agricultural fumigant use and neurodevelopment in 7-year old children.
OBJECTIVES
Our objective was to examine the relationship between residential proximity to agricultural fumigant use and neurodevelopment in 7-year old children.
METHODS
Participants were living in the agricultural Salinas Valley, California and enrolled in the Center for the Health Assessment of Mothers and Children Of Salinas (CHAMACOS) study. We administered the Wechsler Intelligence Scale for Children (4th Edition) to assess cognition and the Behavioral Assessment System for Children (2nd Edition) to assess behavior. We estimated agricultural fumigant use within 3, 5 and 8km of residences during pregnancy and from birth to age 7 using California's Pesticide Use Report data. We evaluated the association between prenatal (n = 285) and postnatal (n = 255) residential proximity to agricultural use of methyl bromide, chloropicrin, metam sodium and 1,3-dichloropropene with neurodevelopment.
RESULTS
We observed decreases of 2.6 points (95% Confidence Interval (CI): -5.2, 0.0) and 2.4 points (95% CI: -4.7, -0.2) in Full-Scale intelligence quotient for each ten-fold increase in methyl bromide and chloropicrin use within 8km of the child's residences from birth to 7-years of age, respectively. There were no associations between residential proximity to use of other fumigants and cognition or proximity to use of any fumigant and hyperactivity or attention problems. These findings should be explored in larger studies.
Topics: Attention; California; Child; Female; Fumigation; Humans; Hyperkinesis; Intelligence Tests; Longitudinal Studies; Pesticides; Pregnancy; Prenatal Exposure Delayed Effects
PubMed: 28686950
DOI: 10.1016/j.envres.2017.06.036 -
Frontiers in Plant Science 2017Mungbean [ (L.) R. Wilczek var. ] is an important pulse crop in Asia, and is consumed as dry seeds and as bean sprouts. It is an excellent source of digestible protein.... (Review)
Review
Mungbean [ (L.) R. Wilczek var. ] is an important pulse crop in Asia, and is consumed as dry seeds and as bean sprouts. It is an excellent source of digestible protein. Bruchids [ (L.) and (F.)] are the important pests of mungbean and cause damage in the field and in storage. Bruchid infestation reduces the nutritional and market value of the grain and renders seeds unfit for human consumption, agricultural and commercial uses. These pests are controlled mainly by fumigation with highly toxic chemicals such as carbon disulfide, phosphene, and methyl bromide, or by dusting with several other insecticides, which leave residues on the grain, thus, threatening food safety. Some plant-based extracts have been found useful in controlling bruchids, but are not fully successful due to their short-term activity, rapid degradability, and potentially negative effect on seed germination. Although some wild sources of bruchid resistance in mungbean have been reported, which have been used to develop bruchid- resistant lines, undesirable genetic linkages threaten the proper exploitation of genetic diversity from wild germplasm into commercial cultivars. Further, biotype variation in bruchids has rendered some mungbean lines susceptible that otherwise would have been resistant to the pest. Host plant resistance is a cost-effective and a safe alternative to control bruchids in mungbean and is associated with morphological, biochemical, and molecular traits. These traits affect insect growth and development, thereby, reduce the yield losses by the pests. Understanding the defense mechanisms against insect pests could be utilized in exploiting these traits in crop breeding. This review discusses different traits in mungbean involved in defense against bruchids and their utility in pest management. We also highlight the breeding constraints for developing bruchid-resistant mungbean and how can these constraints be minimized. We further highlight the importance of supporting conventional breeding techniques by molecular techniques such as molecular markers linked to bruchid resistance.
PubMed: 28676807
DOI: 10.3389/fpls.2017.01031 -
JAMA Dermatology Jul 2017Although Pyemotes species have been known to cause dermatitis, recent reports are rare. During the past 30 years, only 3 outbreaks of dermatitis caused by Pyemotes...
IMPORTANCE
Although Pyemotes species have been known to cause dermatitis, recent reports are rare. During the past 30 years, only 3 outbreaks of dermatitis caused by Pyemotes ventricosus have been reported.
OBJECTIVE
To analyze the causative agent of skin changes in employees of a company that produced herbal medicines.
DESIGN, SETTING, AND PARTICIPANTS
This case series includes 18 patients (8 men, 10 women; mean age, 44 years) who contracted unusual dermatitis after an occupational exposure in July and August of 2012 while working for a company that produced herbal medicines. The patients were examined at the Lower Silesia Regional Centre of Occupational Medicine in Wroclaw, Poland.
EXPOSURES
Workers weighed and packed 1 part of the Helichrysum arenarium herb.
MAIN OUTCOMES AND MEASURES
We hypothesized the causative agent to be P ventricosus. An examination of the herbal specimens for ectoparasites confirmed the diagnosis.
RESULTS
Initially 16 employees developed pruritic skin changes. Skin lesions with pruritic vesicles on an erythematous base with surrounding swelling and edema were observed. Several employees also developed a flulike illness. After 44 days, 2 new employees presented with the same skin changes. The analysis of working conditions showed that the same part of the H arenarium herb was weighed and packed at that time.
CONCLUSIONS AND RELEVANCE
We found that changing the time when the herbs were weighed and abandoning gas fumigation containing methyl bromide resulted in the recurrence of an almost forgotten disease.
Topics: Adult; Animals; Dermatitis, Occupational; Disease Outbreaks; Female; Helichrysum; Humans; Male; Mite Infestations; Mites; Occupational Exposure; Poland; Pruritus; Skin
PubMed: 28445563
DOI: 10.1001/jamadermatol.2017.0323 -
Journal of Nematology Dec 2016Two years of field trials conducted in a infested field evaluated grafting and Paladin Pic-21 (dimethyl disulfide:chloropicrin [DMDS:Pic] 79:21) for root-knot nematode...
Two years of field trials conducted in a infested field evaluated grafting and Paladin Pic-21 (dimethyl disulfide:chloropicrin [DMDS:Pic] 79:21) for root-knot nematode and weed control in tomato and melon. Tomato rootstocks evaluated were; 'TX301', 'Multifort', and 'Aloha'. 'Florida 47' was the scion and the nongrafted control. A double crop of melon was planted into existing beds following tomato harvest. Melon rootstocks, and 'Tetsukabuto', were evaluated with nongrafted 'Athena' in year 1. In year 2, watermelon followed tomato with scion variety 'Tri-X Palomar' as the control and also grafted onto 'Emphasis' and 'Strongtosa' rootstocks. Four soil treatments were applied in fall both years under Canslit metalized film; Paladin Pic-21, methyl bromide:chloropicrin (MeBr:C33, 67:33), Midas (iodomethane:chloropicrin 50:50), and a herbicide-treated control. J in soil were highest in herbicide control plots and nongrafted tomato. All soil treatments produced similar tomato growth, which was greater than the herbicide control. All treatments reduced J in roots compared to the herbicide control. 'Multifort' rootstock produced the largest and healthiest roots; however, the number of isolated from roots did not differ among the tomato rootstocks tested. Galling on tomato was highest in herbicide control plots and nongrafted plants. In melon, J in soil did not differ among melon rootstocks, but numbers isolated from melon rootstocks increased in 'Tetsukabuto' compared with . 'Tetsukabuto' were larger root systems than nongrafted 'Athena'. All fumigants provided protection for all melon rootstocks against galling by compared to the herbicide control. Galling on rootstock was less in all fumigant treatments compared with nongrafted 'Athena' and 'Tetsukabuto'. In watermelon, in soil and roots did not differ among soil treatments or watermelon rootstocks, and yield was lower in both grafted rootstocks compared with the nongrafted control. All soil treatments increased average fruit weight of watermelon compared with the herbicide control, and provided effective weed control, keeping the most predominant weed, purple nutsedge ( L.), density at or below 1/m row. Grafting commercial scions onto -resistant rootstocks has potential for nematode management combined with soil treatments or as a stand-alone component in crop production systems.
PubMed: 28154429
DOI: 10.21307/jofnem-2017-031 -
Scientific Reports Dec 2016N-methyl bromide of lidocaine (QX-314) is a potential local anaesthetic with compromised penetration through cell membranes due to its obligated positive charge....
N-methyl bromide of lidocaine (QX-314) is a potential local anaesthetic with compromised penetration through cell membranes due to its obligated positive charge. Liposomes have been widely used for drug delivery with promising efficacy and safety. Therefore we investigated the local anaesthetic effects and tissue reactions of QX-314 in combination with anionic, cationic or neutral liposomes in rat sciatic nerve block model, and explored the effects of these liposomes on cellular entry of QX-314 in human embryonic kidney 293 cells. The results demonstrated that anionic liposomes substantially prolonged the duration of sensory (25.7 ± 8.3 h) and motor (41.4 ± 6.1 h) blocks of QX-314, while cationic and neutral ones had little effects. Tissue reactions from QX-314 with anionic liposomes were similar to those with commonly used local anaesthetic bupivacaine. Consistent with in vivo results, the anionic liposomes produced the greatest promotion of cellular entry of QX-314 in a time-dependent manner. In conclusion, ultra-long lasting nerve blocks were achieved by a mixture of QX-314 and anionic liposomes with a satisfactory safety profile, indicating a potential approach to improve postoperative pain management. The liposome-induced enhancement in cellular uptake of QX-314 may underlie the in vivo effects.
Topics: Anesthetics, Local; Animals; Immunohistochemistry; Lidocaine; Liposomes; Molecular Structure; Nerve Block; Proton Magnetic Resonance Spectroscopy; Rats; Sciatic Nerve; Time Factors
PubMed: 27924842
DOI: 10.1038/srep38582 -
Insects Dec 2016Nitric oxide (NO) fumigation under ultralow oxygen (ULO) conditions was studied for its efficacy in controlling codling moth and effects on postharvest quality of...
Nitric oxide (NO) fumigation under ultralow oxygen (ULO) conditions was studied for its efficacy in controlling codling moth and effects on postharvest quality of apples. NO fumigation was effective against eggs and larvae of different sizes on artificial diet in 48 h treatments. Small larvae were more susceptible to nitric oxide than other stages at 0.5% NO concentration. There were no significant differences among life stages at 1.0% to 2.0% NO concentrations. In 24 h treatments of eggs, 3.0% NO fumigation at 2 °C achieved 100% egg mortality. Two 24 h fumigation treatments of infested apples containing medium and large larvae with 3.0% and 5.0% NO resulted in 98% and 100% mortalities respectively. Sound apples were also fumigated with 5.0% NO for 24 h at 2 °C to determine effects on apple quality. The fumigation treatment was terminated by flushing with nitrogen and had no negative impact on postharvest quality of apples as measured by firmness and color at 2 and 4 weeks after fumigation. This study demonstrated that NO fumigation was effective against codling moth and safe to apple quality, and therefore has potential to become a practical alternative to methyl bromide fumigation for control of codling moth in apples.
PubMed: 27918417
DOI: 10.3390/insects7040071 -
Journal of Nematology Sep 2016Steam and soil solarization were investigated for control of the root-knot nematode in 2 yr of field trials on a commercial flower farm in Florida. The objective was to...
Steam and soil solarization were investigated for control of the root-knot nematode in 2 yr of field trials on a commercial flower farm in Florida. The objective was to determine if preplant steam treatments in combination with solarization, or solarization alone effectively controlled nematodes compared to methyl bromide (MeBr). Trials were conducted in a field with naturally occurring populations of . Treatments were solarization alone, steam treatment after solarization using standard 7.6-cm-diameter perforated plastic drain tile (steam 1), steam treatment following solarization using custom-drilled plastic drain tile with 1.6-mm holes spaced every 3.8 cm (steam 2), and MeBr applied at 392 kg/ha 80:20 MeBr:chloropicrin. Drain tiles were buried approximately 35 cm deep with four tiles per 1.8 by 30 m plot. Steam application followed a 4-wk solarization period concluding in mid-October. All steam was generated using a Sioux propane boiler system. Plots were steamed for sufficient time to reach the target temperature of 70°C for 20 min. Solarization plastic was retained on the plots during steaming and plots were covered with a single layer of carpet padding to provide additional insulation. The floriculture crops larkspur ( and × ), snapdragon (), and sunflower () were produced according to standard commercial practices. One month after treatment in both years of the study, soil populations of were lower in both steam treatments and in MeBr compared to solarization alone. At the end of the season in both years, galling on larkspur, snapdragon, and sunflowers was lower in both steam treatments than in solarization. Both steam treatments also provided control of in soil at the end of the season comparable to, or exceeding that provided by MeBr. Both steam treatments also reduced in snapdragon roots comparable to, or exceeding control with MeBr. in soil increased in solarization alone. Solarization alone also had higher gall ratings on larkspur, snapdragon, and sunflower than all other treatments. Steam provided excellent control of in this study.
PubMed: 27765992
DOI: 10.21307/jofnem-2017-026 -
Journal of the Science of Food and... Nov 2016
PubMed: 27696429
DOI: 10.1002/jsfa.8020