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3.
Israel Slomnicki 《Potato Research》1961,4(3):201-210
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.
Publication of the National and University Institute of Agriculture, Rehovot, 1960. Series No. 354-E. 相似文献
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
4.
Empirical relationships between land use/cover and estuarine condition in the Northeastern United States 总被引:1,自引:0,他引:1
Wilfrid Rodriguez Peter V. August Yeqiao Wang John F. Paul Arthur Gold Norman Rubinstein 《Landscape Ecology》2007,22(3):403-417
Land–water interactions were examined in three regions in the Virginian Biogeographic Province; the southern shore of Cape
Cod, Massachusetts; the Hudson/Raritan region of New York; and the eastern shore of the Delmarva (Delaware/Maryland/Virginia)
Peninsula. Cumulative distribution functions were used to evaluate similarity in environmental condition among estuaries.
Spatial-setting variables (location in a river, coastal lagoon, or in open waters) were associated with variation for some
measures of estuarine condition. Patterns of coastal urban and agriculture gradients were measured and their relationship
with indicators of estuarine condition was modeled statistically. When estuaries were pooled, the highest variation explained
by spatial-setting variables was found for dissolved oxygen (DO, R
2 = 0.44) and salinity (R
2 = 0.58), with DO decreasing in river locations and salinity decreasing with rainfall and sampling locations near rivers.
The explanatory power for the other indicator variables was low and varied from 6% to 27%. Rainfall explained some of the
variation (R
2 = 0.23) in total suspended solids. Moderate (0.4 < | r | < 0.7) to strong (| r | ≥ 0.7) linear associations were found between total urban area and measures of estuarine condition. Within regions, total
urban area was positively associated with Silver (r = 0.59), Cadmium (r = 0.65), and Mercury (r = 0.47) in Cape Cod, and inversely related to DO (r = −0.65) in the Hudson/Raritan region. No associations were found in the Delmarva Peninsula study area. Total area of agriculture
showed a moderate association with Arsenic in Cape Cod, but no other associations were found in the other two regions. Our
analyses show a measurable impact of urban land use on coastal ecosystem condition over large areas of the northeastern United
States. This pattern was most evident when many different landscapes were considered simultaneously. The relationship between
urban development and estuarine condition were weaker within the individual regions studied. The use of land use/cover models
for predicting estuarine condition is a challenging task that warrants enhancements in the type, quantity, and quality of
data to improve our ability to discern relationships between anthropogenic activities on land and the condition of coastal
environments. 相似文献
5.
Forty 11- to 13-month-old Friesian calves were inoculated with live Babesia bovis vaccine. Twenty of the calves were treated with long acting oxytetracycline seven and 15 days after receiving the vaccine. Parasites were detected in nine of the treated calves compared with all 20 of the untreated control group. Treated calves were less febrile and had higher packed cell volumes than control animals. All calves from both groups developed a considerable antibody titre to B bovis. It appears that long acting oxytetracycline can mitigate the response of sensitive cattle breeds to live antibabesial vaccine and prevent damage caused by excessive multiplication of B bovis parasites. 相似文献
6.
Israel Sánchez-Osorio Gloria López-Pantoja Antonia M. Paramio José L. Lencina Diego Gallego Luis Domínguez 《Journal of pest science》2016,89(1):59-68
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
7.
Di Paola-Naranjo RD Baroni MV Podio NS Rubinstein HR Fabani MP Badini RG Inga M Ostera HA Cagnoni M Gallegos E Gautier E Peral-Garcia P Hoogewerff J Wunderlin DA 《Journal of agricultural and food chemistry》2011,59(14):7854-7865
Our main goal was to investigate if robust chemical fingerprints could be developed for three Argentinean red wines based on organic, inorganic, and isotopic patterns, in relation to the regional soil composition. Soils and wines from three regions (Mendoza, San Juan, and Co?rdoba) and three varieties (Cabernet Sauvignon, Malbec, and Syrah) were collected. The phenolic profile was determined by HPLC-MS/MS and multielemental composition by ICP-MS; (87)Sr/(86)Sr and δ(13)C were determined by TIMS and IRMS, respectively. Chemometrics allowed robust differentiation between regions, wine varieties, and the same variety from different regions. Among phenolic compounds, resveratrol concentration was the most useful marker for wine differentiation, whereas Mg, K/Rb, Ca/Sr, and (87)Sr/(86)Sr were the main inorganic and isotopic parameters selected. Generalized Procrustes analysis (GPA) using two studied matrices (wine and soil) shows consensus between them and clear differences between studied areas. Finally, we applied a canonical correlation analysis, demonstrating significant correlation (r = 0.99; p < 0.001) between soil and wine composition. To our knowledge this is the first report combining independent variables, constructing a fingerprint including elemental composition, isotopic, and polyphenol patterns to differentiate wines, matching part of this fingerprint with the soil provenance. 相似文献
8.
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
9.
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
10.
Luis Alvarez-Lajonchegre Vinicius R. Cerqueira Israel D. Silva Jaqueline Araujo Marcosdos Reis 《Journal of the World Aquaculture Society》2002,33(4):506-516
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