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Cerambyx welensii Küster is one of the greatest threats to Quercus suber L. and Quercus ilex L. in Spain. Efficient control methods for this species are currently being tested, and the use of traps baited with food-related products for their monitoring and control has been proposed. Cerambyx welensii adults prefer to colonize old or decayed trees, in which cortical exudates frequently release fermentation odors. Fermentation-related compounds, such as ethanol, have been cited as attractants to various hardwood woodborers (as Cerambyx cerdo L.), used either alone or sometimes in combination with other host odors. In this work, we conducted field experiments to ascertain whether chemical blends mimicking fermentation odors were attractive for C. welensii. To this end, we used three types of traps (multiple funnel, cross-vane and single-funnel) baited with six synthetic blends including one or more fermentation-related chemicals (ethanol, ethyl acetate, 3-methyl-1-butanol, acetaldehyde, 2-methyl-1-propanol and 2-methyl-1-butanol), various food-related products (beer, melon and red wine mixed with peach juice) and host monoterpenes (α-pinene, β-pinene, limonene, α-phellandrene and camphene). At high release rates (5–11 g/day), various synthetic blends proved attractive irrespective of trap type. Our results contribute to understand the impact of volatile organic compounds in host selection by woodborers infesting deciduous trees. The results hold promise for optimizing trapping strategies to control C. welensii within an integrated pest management framework.  相似文献   
3.
In a 2-year field study, the effects of four heating regimes established by varying temperature or duration of heating on efficiency of on-farm wastes as soil amendments in controlling Fusarium oxysporum f.sp. cumini (Foc) causing wilt on cumin (Cuminum cyminum L.), were ascertained. Significant improvement in reduction of Foc propagules was achieved with the increase in duration and amount of heat. In 2000, mild heating under shade (heat level 4), 31.8–65.9% reduction in Foc propagules was estimated in all the amendments at 0–30 cm soil depth, which improved by 75.7–86.5% in the treatment where Foc-infested soil brought from the laboratory was exposed to direct heat (heat level 3) and amendments and irrigation were applied. Foc propagules were reduced by 76.6–88.3% when infested soil was exposed continuously to dry heat for 56 days (heat level 2), improving efficiency of amendments by 0.9–13.5% compared with heat level 3. After 56 days of exposure to dry heat, elevating the temperature by mulching amended soil with a transparent polyethylene film (50 μm thick) for 20 days (heat level 1) augmented reduction by 80.2–95.5%. In the second season, combining 0.04% of onion, Verbisina encelioides or mustard oil-cake with mustard residues (0.18%) improved the reduction in Foc propagules at all heat levels even at the lower soil depth. Maximum reduction (94.9–100%) in Foc propagules at heat levels 1 to 3 was achieved when residues of Verbisina were supplemented with those of mustard. These results suggest a new approach to improve the control of Foc by combining prolonged heating with on-farm wastes such as Verbisina residues and one summer irrigation.  相似文献   
4.
Summary Autumn grown potatoes harvested in December cannot be used for planting in February–March, as they are still dormant at that time. The lengthy dormant period ofUp-to-Date, the main variety cultivated in Israel, was found to be the bottleneck of the problem of supply of locally grown seed tubers. In order to find varieties with a shorter dormant period, 52 varieties from different sources were introduced. The seed material was propagated twice before it was used for the first screening test in spring 1956. The first test has shown that varieties with a short dormant period gave the best results and those with a long one the worst. The second screening in spring 1957, in which a limited number of the most promising varieties were tested, has shown that length of growing period is at least as important as length of dormant period, and that early and medium-early varieties are best. In spite of the results obtained we consider that it will be necessary to breed new varieties more adapted to the specific requirements of growing two crops a year.
Zusammenfassung Im Herbst ausgepflanzte und im Dezember geerntete Kartoffeln k?nnen nicht zum Auspflanzen im Februar verwendet werden, da sie sich dann noch in der Keimruhe befinden. Die ziemlich lange Keimruhe vonUp-to-Date, der in Israel am meisten angebauten Sorte, erwies sich als die gr?sste Schwierigkeit bei der L?sung des Problems der Versorgung mit einheimischem Saatgut. Um Sorten mit kürzerer Keimruhe zu finden, wurden 52 Sorten verschiedener Herkunft eingeführt. Das Saatgut wurde zweimal fortgezüchtet, bevor es für den ersten Auslesetest im Frühjahr 1956 verwendet wurde. Der erste Versuch zeigte, dass Sorten mit kurzer Keimruhe die besten und Sorten mit langer Keimruhe die schlechtesten Resultate ergaben. Die zweite Auslese im Frühjahr 1957, wobei eine kleinere Anzahl der aussichtsreichsten Sorten geprüft wurde, zeigte, dass die Dauer der Wachstumsperiode mindestens ebenso wichtig ist wie die L?nge der Keimruhe und dass frühe und mittelfrühe Sorten die besten sind. Ungeachtet dieser Ergebnisse halten wir es für angezeigt, neue Sorten zu züchten, die den besonderen Ansprüchen einer zweimaligen Ernte im Jahr besser genügen.

Résumé Les pommes de terre d'automne récoltées en décembre ne peuvent servir de semence en févriermars, puisqu'elles se trouvent encore à l'état latent à cette époque. La période de latence assez prolongée de l'Up-to-date, la principale variété cultivée en Israel, constitue le majeur obstacle à l'approvisionnement en semences locales. Afin de trouver des variétés à courte période de latence, nous avons introduit 52 variétés de différentes provenances. Celles-ci ont d? être multipliées deux fois avant que nous ayons pu entreprendre le premier essai au printemps 1956. Ce premier essai a permis de constater que les variétés à courte période de latence étaient les meilleures, celles à période de latence prolongée donnant les résultats les moins bons. La seconde sélection fut effectuée au printemps 1957. A cette occasion, un plus petit nombre de variétés particulièrement prometteuses furent étudiées. Il fut constaté que la durée de végétation a une importance au moins égale à celle de la durée de latence. Les variétés précoces et moyennes étaient les meilleures. Malgré les résultats de cette étude, nous en sommes arrivés à cette conclusion qu'il nous faudra sélectionner, des variétés nouvelles, mieux adaptées aux exigences particulières de la culture de la pomme de terre effectuée à deux reprises dans la même année.


Publication of the National and University Institute of Agriculture, Rehovot, 1960. Series No. 354-E.  相似文献   
5.
The objective of research was to conduct a survey related to the production process for fura. Fura is a staple food for the Fulanis and Hausas. The single most important cereal grain for fura production is millet. A significant difference exists among respondents on the variety of millet chosen for fura production. A significantly greater proportion (p=0.05) indicated that `gero' is the variety in common use. Spices are indispensable as an ingredient in fura production with ginger being the single most important spice (p=0.01). The traditional pounding method for processing millet into flour is still very much used. The implication of this is highlighted and a possible solution of optimizing fura production process is recommended. Strictly speaking, fura is distributed with a minimum of packaging. The choice of suitable package provided protection during a generally short shelf-life and for local distribution. With increasing influence of advertising upon customers, small food processing enterprises making fura will have to improve the packaging and preservation of their products if they are to survive the competition.  相似文献   
6.
A pilot‐scale trial to rear fat snook Centropomus parallelus through larval, weaning and nursery phases was conducted in Florianópolis, Brazil. Eggs (96% fertilization) from captive broodstock, induced to spawn using 50 μg/kg LHRHa were stocked in two 4,000‐L cylindrical fiberglass tanks at a mean density of 19.2 eggs/L. Nannochloropsis oculata was stocked with the eggs and maintained at a mean density of 0.5–1.0 ± 106 cells/mL up to 31 dph (31 dph). Hatching averaged 90%. Larvae were fed rotifers Brachionus rotundiformis enriched with an oil emulsion from 3 dph to 36 dph (30–40 rotifers/mL) and Artermia meta‐nauplii enriched with Selco from 22 dph to 60 dph (mean 2.9 meta‐nauplii/mL). Weaning began at 45 dph with an artificial dry diet NRG (50% protein), supplied together with concentrated and enriched Artemia meta‐nauplii. No critical period of mortality was observed during larval rearing. During the 43 days of weaning and nursery, less than 1% mortality was recorded. Food conversion rate during nursery was 1.17, with a change in the coefficient of variation of mean total length of 1.3%. Specific total growth rate in weight was 13.0 %/d and mean growth in total length and total weight were 0.65 mm/d and 24.0 mg/d over the whole rearing trial respectively. Mean total length and total weight of juveniles were 57.6 ± 0.1 mm and 2.11 ± 0.12 g, respectively, and the length‐weight relationship was W = 8.29931 ± 10–5 TL3.049607 (r= 0.9986). on 88 dph when the trial was terminated. The condition factor on 88 dph was 1.104. On 88 dph a total of 35,000 juveniles were harvested, overall survival was 25.5% with mean final density of 4.4 fishn and biomass of 6.9 kg/m3. The present trial demonstrated the feasibility of mass production of fat snook. Possible improvements necessary for commercial cultivation of fat snook C. parallelus are discussed.  相似文献   
7.
热应激影响高产奶牛的生产与繁殖性能。在以色列,奶牛的受胎率冬季为50%,到夏季就降到20%以下了。夏季奶牛的发情行为也相对没有那么强,并伴随着繁殖率低、产犊间隔增加、生产效率较低以及造成供应乳品厂原奶的季节性问题等。在以色列,夏季所产牛奶的乳蛋白和乳脂含量降低,而体细胞数增加,造成牛奶质量的明显下  相似文献   
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In this study we examined the direct effects of bovine herpesvirus-1 on the interaction of bovine blood neutrophils with Pasteurella haemolytica A1. Preincubation of neutrophils for approximately 2 h in vitro with BHV-1 at a multiplicity of infection of 5:1 had no effect on neutrophil random migration and directed migration to zymosan-activated bovine serum. Neutrophils also were unimpaired in their ability to ingest and kill P. haemolytica A1. Preincubation of neutrophils with BHV-1 did not elicit an oxidative burst, as measured by luminol-enhanced chemiluminescence, nor did it alter neutrophil chemiluminescence in response to opsonized P. haemolytica A1. Prolonged preincubation with BHV-1 for 18-24 h similarly did not affect neutrophil chemiluminescence in response to opsonized P. haemolytica A1. The susceptibility of neutrophils to the lethal effects of crude P. haemolytica cytotoxin also was unaltered by preincubation with BHV-1. We observed no evidence of BHV-1 replication in bovine neutrophils as determined by indirect immunofluorescence and electron microscopy. Previous reports have indicated that active BHV-1 infection alters certain neutrophil functions and results in hypersusceptibility to pulmonary pasteurellosis. Our results suggest that these effects are unlikely to be mediated directly by BHV-1, but instead may reflect the action of endogenous mediators that are released during active BHV-1 infection.  相似文献   
10.
ABSTRACT The population structure of Pepino mosaic virus (PepMV), which has caused severe epidemics in tomato in Spain since 2000, was analyzed. Isolates were characterized by the nucleotide sequence of the triple gene block and coat protein gene and, for a subset of isolates, a part of the RNA-dependent RNA polymerase gene. The full-length sequence of the genomic RNA of a Solanum muricatum isolate from Peru also was determined. In spite of high symptom diversity, the Spanish population of PepMV mostly comprised highly similar isolates belonging to the strain reported in Europe (European tomato strain), which has been the most prevalent genotype in Spain. The Spanish PepMV population was not structured spatially or temporally. Also, isolates highly similar to those from nontomato hosts from Peru (Peruvian strain) or to isolate US2 from the United States (US2 strain) were detected at lower frequency relative to the European strain. These two strains were detected in peninsular Spain only in 2004, but the Peruvian strain has been detected in the Canary Islands since 2000. These results suggest that PepMV was introduced into Spain more than once. Isolates from the Peruvian and US2 strains always were found in mixed infections with the European tomato strain, and interstrain recombinants were detected. The presence of different strains of the virus, and of recombinant isolates, should be considered for the development of control strategies based on genetic resistance.  相似文献   
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