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101.
Field trials were carried out to assess the efficacy of a 4% azadirachtin (aza)-containing neem seed extract EC, against damage
by western flower thrips [Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)] on nectarine crops in the Similkameen Valley, British Columbia, Canada. Several trials
were conducted during the years 1993 to 1995 to assess the repellent and larvicidal properties of aza, specifically: whether
it was effective against adult or larval thrips; how the effects differed with concentration of aza; and whether female WFT
avoided aza-treated flowers. Our results showed that aza has only limited effectiveness as a control agent against WFT on
nectarines and the current formulation does not appear to limit larval development sufficiently to be deemed a possible control
agent in this field situation. 相似文献
102.
A 2004–2005 survey of potatoes from stores in the north‐central potato‐producing region of the USA showed that the predominant causes of dry rot were Fusarium graminearum and Fusarium sambucinum. Isolates of F. graminearum originally isolated from potato tubers with dry rot (n = 15), wheat kernels with scab (n = 15), and sugarbeet tap roots with decay (n = 5) were tested for aggressiveness to potato tubers. There were no significant differences in aggressiveness among isolates of F. graminearum, regardless of original host, as measured by their ability to cause dry rot. These findings may have implications for survival of F. graminearum inoculum since potatoes, wheat and sugarbeets are frequently used in crop rotation in the region. Fusarium graminearum required larger wounds for infection of potato tubers than F. sambucinum. Plug‐removal injury, simulating a stolon‐removal injury, resulted in equal incidence of dry rot caused by the two Fusarium species, whereas abrasion and bruising injury were sufficient for infection and dry rot development by F. sambucinum, but not F. graminearum. A change in harvest practices from vine‐killing prior to harvest to mechanical vine‐killing on the day of harvest may be a factor affecting the onset of dry rot caused by F. graminearum, since this process often causes large wounds at the stem end of the tubers when the stolon is forcibly removed. 相似文献
103.
ABSTRACT One hundred two single zoospore isolates of Phytophthora infestans, derived asexually from four parental isolates of US-8 genotype and one isolate of US-1 genotype, were characterized for their virulence phenotypes to determine changes in virulence during asexual reproduction. Potato differentials, each containing a major gene for resistance to P. infestans (R1 to R11), were used to characterize the virulence patterns. Isolates were also characterized for mating type, glucose-6-phosphate isomerase (Gpi) banding pattern, and DNA fingerprints using probe RG57 to determine any genotypic changes in the single zoospore isolates. A subset of these single zoospore isolates was tested for response to mefenoxam to determine any shifts in sensitivity. Results showed that single zoospore isolates derived from parent PI-1 (US-8, 11 isolates) were identical to their parental virulence. Isolates derived from parent PI-191 (US-8, 29 isolates) showed some differences in virulence, mainly toward R8 and R9. Isolates derived from parent PI-126 (US-8, 14 isolates) demonstrated a higher level of virulence diversity. Isolates derived from parents PI-52 (US-1, 28 isolates) and PI-105 (US-8, 20 isolates) showed the highest level of virulence variability among the single zoospore isolates. Mating type, Gpi banding pattern, and DNA fingerprints for the single zoospore isolates were, in most cases, identical to the parental isolates. Single zoospore isolates showed different levels of sensitivity to mefenoxam. Virulence and other genetic changes during asexual reproduction are likely to play a major role in changing the race structure of P. infestans populations. This continuous change in the race structure is a serious problem and now poses a new challenge for utilization of race-specific resistance to manage late blight of potato. 相似文献
104.
P Zwart M A Verwer G A De Vries E J Hermanides-Nijhof EJ+HERMANIDESAANIJHOF H W De Vries HW+DEVRIES 《The Journal of small animal practice》1973,14(12):773-779
In a rainbow boa (Epicrates chenchria maurus) an affection of the spectacle of the eyes caused by the fungus Fusarium oxysporum is described for the first time. Enucleation was performed under premedication of Hypnodil and inhalation anesthesia with tracheal intubation, using Halothane. Résumé. On décrit, pour la première fois, chez le boa Epicrates chenchria maurus une affection des paupières transparentes causée par le fongus Fusarium oxysparum. L'énucléation a été faite sous prémédication d'Hypnodil et d'inhalation anesthésie avec intubation trachéale, utilisant Halothane. Zusammenfassung. In einer Boa, Epicrates chenchria maurus, wurde eine Erkrankung von der durchsichtigen Kapsel über dem Auge, verursacht durch den Fungus Fusarium oxysporum zum ersten Ma1 beschrieben. Enukleation wurde vorgenommen, unter Basisnarkose van Hypnodil und Einatmungsanästhesie mit trachealer Intubation, indem man Halothane gebrauchte. 相似文献
105.
FJF Sant''Ana EF Nascimento EJ Gimeno CG Barbeito 《Reproduction in domestic animals》2005,40(1):40-45
This study was carried out to compare the lectin-binding pattern in the normal and pathological oviduct of sows during the ovarian cycle. Lectin-binding patterns showed differences between segments, phases of ovarian cycle and presence of morphologic lesions. In the infundibulum, it was observed that the cysts, in the follicular phase, reduced Ricinus communis-I (RCA-I) and Ulex europaeus-I (UEA-I) binding. Furthermore, in the pathological oviducts of the luteal-phase group, there is a reduction of Concanavalia ensiformis (Con-A) reactivity in this segment of the tube having wall cysts, adenomyosis and diverticulus. The Arachis hypogaea (PNA) binding in the infundibulum, during the luteal phase, decreased in the tube having adenomyosis. In animals with wall cysts, the Con-A, Triticum vulgaris (WGA) and RCA-I reactivity was minor in the glycocalyx of the isthmus epithelium during follicular phase. Con-A and Dolichos biflorus (DBA) binding pattern was minor in the luteal-phase isthmus of the tube having wall cysts, adenomyosis and diverticulus. In the ampulla, the wall cysts impaired the Con-A reaction only in the basal region of the epithelium, in the follicular phase. Binding with Con-A was decreased in the ampulla of animals in the luteal phase in the tube lesions with cysts and diverticulus. In addition, the diverticulus observed in the ampulla, during the luteal phase, reduced the PNA tubaric binding. The results of this study showed that the morphologic alterations modify the sugar pattern in the oviduct of sows. These modifications in glycoconjugates may be one of the reasons for the failure of fertility in sows. 相似文献
106.
Leopards Panthera pardus are classified in the IUCN Red List as Vulnerable, primarily due to habitat loss, natural prey base depletion and exploitation caused by various anthropogenic activities. Although protected areas are important for leopard conservation, the majority of suitable leopard habitat lies beyond protected area boundaries exposing individuals to different environmental, physiological and psychosocial stressors. This study aimed to examine the suitability of five different enzyme immunoassays (EIAs) for monitoring adrenocortical function in the leopard based on faecal glucocorticoid metabolite (fGCM) analysis. After performing an adrenocorticotrophic hormone (ACTH) stimulation test and investigating the stability of fGCM post-defaecation, faeces from free-ranging leopards in a peri-urban and a conservation area were collected to investigate the potential impact of habitat variability on glucocorticoid output. An EIA measuring fGCM with a 5α-3β-11β-diol structure performed best, demonstrating a ~200%–330% increase in fGCM concentrations approximately 40 h post-ACTH administration. Concentrations of fGCM remained quite stable for up to six days post-defaecation and showed a maximum increase of 8% and a maximum decrease of 9%. Although not significantly different, overall median fGCM concentrations were 68% higher in individuals utilising the peri-urban area compared with leopards utilising the conservation area. The ranges of fGCM concentrations between sites, however, were similar. Individual median fGCM concentrations differed distinctly between free-ranging males and females, possibly linked to female reproductive status. The established method can now assist in addressing some of the issues facing local wildlife managers, conservationists and researchers tackling various aspects related to leopard conservation and management under different land-use practices. 相似文献
107.
Jay R. Rooker David H. Secor Vincent S. Zdanowicz Gregorio De Metrio Lidia Orsi Relini 《Fisheries Oceanography》2003,12(2):75-84
Chemical signatures in the otoliths of teleost fishes represent natural tags that may reflect differences in the chemical and physical characteristics of an individuals' environment. Otolith chemistry of Atlantic bluefin tuna (Thunnus thynnus) was quantified to assess the feasibility of using these natural tags to discriminate juveniles (age 0 and age 1) from putative nurseries. A suite of six elements (Li, Mg, Ca, Mn, Sr and Ba) was measured in whole otoliths using solution‐based inductively coupled plasma mass spectrometry. Otolith chemistry of age‐1 T. thynnus collected from the two primary nurseries in the Mediterranean Sea and western Atlantic Ocean differed significantly, with a cross‐validated classification accuracy of 85%. Spatial and temporal variation in otolith chemistry was evaluated for age‐0 T. thynnus collected from three nurseries within the Mediterranean Sea: Alboran Sea (Spain), Ligurian Sea (northern Italy), and Tyrrhenian Sea (southern Italy). Distinct differences in otolith chemistry were detected among Mediterranean nurseries and classification accuracies ranged from 62 to 80%. Interannual trends in otolith chemistry were observed between year classes of age‐0 T. thynnus in the Alboran Sea; however, no differences were detected between year classes in the Tyrrhenian Sea. Age‐0 and age‐1 T. thynnus collected from the same region (Ligurian Sea) were also compared and distinct differences in otolith chemistry were observed, indicating ontogenetic shifts in habitat or elemental discrimination. Findings suggest that otolith chemistry of juvenile T. thynnus from different nurseries are distinct and chemical signatures show some degree of temporal persistence, indicating the technique has considerable potential for use in future assessments of population connectivity and stock structure of T. thynnus. 相似文献
108.
Riquelme CA Magida JA Harrison BC Wall CE Marr TG Secor SM Leinwand LA 《Science (New York, N.Y.)》2011,334(6055):528-531
Burmese pythons display a marked increase in heart mass after a large meal. We investigated the molecular mechanisms of this physiological heart growth with the goal of applying this knowledge to the mammalian heart. We found that heart growth in pythons is characterized by myocyte hypertrophy in the absence of cell proliferation and by activation of physiological signal transduction pathways. Despite high levels of circulating lipids, the postprandial python heart does not accumulate triglycerides or fatty acids. Instead, there is robust activation of pathways of fatty acid transport and oxidation combined with increased expression and activity of superoxide dismutase, a cardioprotective enzyme. We also identified a combination of fatty acids in python plasma that promotes physiological heart growth when injected into either pythons or mice. 相似文献
109.
A. L. Thompson B. L. Farnsworth G. A. Secor N. C. Gudmestad D. A. Preston H. Hatterman-Valenti 《American Journal of Potato Research》2006,83(5):373-379
‘Dakota Jewel’ is a medium- to late-maturing potato (Solanum tuberosum L.) cultivar; however, tuber maturity is early. Tubers are smooth, round to oblong in shape, with bright red skin and white flesh. Dakota Jewel is suitable for the fresh tablestock market, both directly from the field and following storage. Yield potential is medium, with total yield, U.S. No. 1s and percentage U.S. No. 1s of Dakota Jewel equal to those of Red Norland; size distribution is similar. Dakota Jewel sizes early, retains its color in storage, and has strong dormancy. It is susceptible to hollow heart. A mean specific gravity of 1.077 across non-irrigated and irrigated sites in North Dakota is much higher than Red Norland and Red Pontiac, standard red tablestock cultivars. Sensory evaluation scores of baked, boiled, and microwaved tubers are similar to Red Norland and Red Pontiac. Dakota Jewel was released by the North Dakota Agricultural Experiment Station on 26 March 2004. 相似文献
110.
Richard G. Novy Robert H. Johansen Gary A. Secor Bryce L. Farnsworth Jim H. Lorenzen Neil C. Gudmestad Edna T. Holm 《American Journal of Potato Research》1997,74(1):31-37
NorDonna is a mid-season, red-skinned, white-fleshed cultivar that yields a large percentage of U.S. No. 1 tubers in diverse growing areas under both dryland and irrigated conditions. It tends to have a darker red skin and a lower incidence of hollow heart when compared to other red cultivars. Intended for tablestock use, NorDonna has baking, boiling, and microwaving properties comparable to Red Pontiac or Red Norland. The North Dakota Agricultural Experiment Station released NorDonna on April 28, 1995. 相似文献