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131.
132.
Zusammenfassung. Die chemische Analyse von am naturlichen Standort behandelten SpartinapRanzen ergab, dass Paraquat sowohl in nach der Behandlung weiterwachsenden Pflanzen als auch in solchen deren oberirdische Teile vernichtet worden waren, in die unterirdischen Teile abgeleitet wurde. In Labortests konnte die Translokation von einem paraquatbehandelten Blatt in andere Sprosse derselben Pflanze nachgewiesen werden. In Gewachshausversuchen, in welchen Paraquat in 4 Entwicklungsstadien zwischen Keimung und Blute angewandt wurde, nahm die Empfindlichkeit gegenuber 2,25 kg/ha Paraquat mit zunehmendem Alter der Spartina pRanzen ab. Diese zunehmende Widerstandsfahigkeit hing weder mit der Entwicklung des Rhizomsystems noch mit dem Blutenansatz zusammen. Solange keine neuen Untersuchungsergebnisse vorliegen, sollte daher Paraquat nicht zur Vernichtung reifer Spartina rasen verwendet werden. Dagegen scheinen Versuche zur Vernichtung von Keimlingen und sehr jungen Pflanzen, die in offene Stellen der Vorkustenzone eindringen, erfolgversprechend. 相似文献
133.
Summary. Trials with dalapon, paraquat and fenuron in 1963 and 1964, and with bromacil and amitrole-T in 1964, were carried out on mature Spartina sward. Dalapon, paraquat and fenuron all gave complete kill on some plots in 1963. In 1964, paraquat gave variable results and lower percentage kills than in 1963, whereas dalapon and fenuron were more consistent. Fenuron allowed a greater degree of regeneration than dalapon and was uneconomic at the high dose (60 lb/ac) required for complete kill. Dalapon gave the best results and with 100 lb/ac there was 98–100% kill 2 years after treatment. At 50 lb/ac results were initially good, but there was more regeneration in the second season after spraying. Bromacil at 5 and 20 lb/ac and a mixture of 5 lb/ac bromacil and 4 lb/ac amitrole-T maintained more than 99% kill lor 2 years after application.
La lutte chimique contre les formes fertiles de Spartina townsendii (s.l.) sur la cóte du Cheshire dans l'esluaire de la Dee I. Essais au champ sur des pelouses de Spartina 相似文献
La lutte chimique contre les formes fertiles de Spartina townsendii (s.l.) sur la cóte du Cheshire dans l'esluaire de la Dee I. Essais au champ sur des pelouses de Spartina 相似文献
134.
The design, construction and performance of an experimental tractor-mounted machine to apply herbicides to small field plots is described. The machine has five spray units, each with five rotating discs. Uniform sized drops in the range from 150 to 350 μm can be produced with lipophilic, hydrophilic and emulsifiable formulations. Spray volumes can be varied from 5 to 120 1/ha. A preliminary assessment of the physical performance of the machine is presented. 相似文献
135.
CE Reid BD Gartrell M Van Andel KJ Stafford EO Minot K McInnes 《New Zealand veterinary journal》2020,68(2):84-91
ABSTRACTAims: To characterise and classify wounds in sheep suspected to have been caused by attacks by kea (Nestor notabilis) (kea strike), and to report the prevalence of these wounds on five high country farms in the South Island of New Zealand.Methods: Data were collected from farms between 28 August 2012 and 20 September 2013. Sheep were examined opportunistically immediately after shearing for signs of wounds caused by kea. The age and sex of sheep were also recorded. Wounds were measured and characterised as recent, healing, or healed, and the estimated true prevalence was calculated for each farm.Results: Injuries consistent with kea strike wounds were identified in 70/13,978 (0.5%) sheep examined. The estimated true prevalence varied between farms, from 0 (95% CI?=?0–0.16) to 1.25 (95% CI?=?0.97–1.61)%. Of the 76 wounds identified, 61 (80%) were located in the lumbar region, and 74 (97%) consisted of full-thickness ulceration of the skin, one showed evidence of injury to muscle and one to bone. The median length of the 63 wounds measured was 6 (min 1, max?23.5) cm, and 10/63 (13%) were categorised as recently healed, 47/63 (62%) as healing, and 17/63 (22%) as recent wounds.Conclusions: The results of this study show that kea strike on sheep was occurring at a low prevalence on the high country farms surveyed. The wounds identified were survivable, but the welfare impact of kea strike on sheep should be considered in balance with the conservation status of kea. There was clear variation in the prevalence of wounds attributed to kea strike between the farms but we were not able to identify the risk factors contributing to these differences. Future studies of kea strike should examine variables such as altitude, local kea density and distribution, and differences in kea strike management and husbandry practices, and should include high country farms without a history of kea strike. 相似文献
136.
Isolates of Pseudomonas syringae pv. phaseolicola from Africa and other bean growing areas were categorized into nine races on the basis of their reactions to eight differential cultivars following artificial inoculation. Eight hundred and ninety-three isolates representing 303 disease occurrences were initially identified as P.s. pv. phaseolicola by their pathogenicity to bean, cultural and serological characteristics and phage sensitivity. These tests also served to distinguish P.s. pv. phaseolicola from the closely related pathovars P.s . pv. glycinea and P.s. pv. syringae . Detailed race determinations were carried out on 175 selected isolates of p.s. pv. phaseolicola representative of the different geographical regions and hosts in which the pathogen was found and nine races were identified. A number of races (1,2,5,6 and 7) were distributed worldwide with race 6 predominant. Other races were found mainly in Africa; races 3 and 4 in East/Central Africa and races 8 and 9 in Southern Africa. Most isolates were obtained from the major host, Phaseolus vulgaris . Alternative natural hosts included 10 legume species representative of seven different genera ( Cajanus cajan, Desmodium sp., Lablab purpureus, Macroptilium atropurpureum, Neonotonia wightii, Phaseolus acutifolius, P. coccineus, P. lunatus, Vigna angularis and V. radiata ). Of these, Desmodium sp. constitutes a new host record. 相似文献
137.
One thousand and forty-eight Phaseolus bean accessions were evaluated for resistance to six races of Pseudomonas syringae pv. phaseolicola . The accessions originated from regions of the Americas and Africa where the disease is important and included wild type accessions and some known resistance sources. Resistance, graded on a five-point scale, was of two types: qualitative, which was shown to be race-specific, and quantitative. Race specific resistance genes (R-genes) were detected in 49.4% of accessions with the following gene frequencies: R1 (10.3%), R2 (0.3%), R3 (25.0%), R4 (35.0%) and R5 (0.2%).
Evidence for quantitative variation in resistance, in the absence of specific R-genes, was shown by the distribution of infection scores, 76% of accessions showing maximum susceptibility (grades 4–5), 23% showing intermediate resistance (grades 2–4), and 1% showing high levels of quantitative resistance (grades 1–2). The last 1% of accessions showed interactions which were not race-specific and it is suggested that they may possess race non-specific resistance. It is possible that several of the accessions in this category carry the recessive gene derived from PI 150414. Other accessions were of unknown parentage and may represent new sources of quantitative, potentially race non-specific, resistance. It is suggested that the combination of race specific and race non-specific resistance could provide an effective strategy for establishing durable resistance. 相似文献
Evidence for quantitative variation in resistance, in the absence of specific R-genes, was shown by the distribution of infection scores, 76% of accessions showing maximum susceptibility (grades 4–5), 23% showing intermediate resistance (grades 2–4), and 1% showing high levels of quantitative resistance (grades 1–2). The last 1% of accessions showed interactions which were not race-specific and it is suggested that they may possess race non-specific resistance. It is possible that several of the accessions in this category carry the recessive gene derived from PI 150414. Other accessions were of unknown parentage and may represent new sources of quantitative, potentially race non-specific, resistance. It is suggested that the combination of race specific and race non-specific resistance could provide an effective strategy for establishing durable resistance. 相似文献
138.
AIM: To determine the suitability of a reversible, injectable anaesthetic combination including medetomidine, butorphanol and atropine to produce the degree of immobilisation required to allow blood sampling in young pigs. METHODS: Twenty 6-week-old crossbred, intact male pigs were sedated with an intramuscular (I/M) injection of 80 µ'g/kg medetomidine, 200 µ'g/kg butorphanol and 25 µ'g/kg atropine. Heart and respiratory rates and rectal temperatures were monitored. Excessive salivation, gagging, laryngeal reflex, presence of pedal reflex and deep and surface analgesia were noted. Time of injection and the time when pigs reached mild and full sedation were also recorded. RESULTS: Mild sedation was produced in 90% of pigs after 5.6 (SEM 0.96) min (n=18; median 5, range 2–16 min), and full sedation (lateral recumbency and loss of jaw tone) in 60% of pigs after 12.5 (SEM 2.14) min (n=12; median 10, range 5-28 min). The depth and duration of sedation were very variable and most animals were easily aroused. Ninety percent of the animals required the administration of halothane by mask to allow blood sampling, but the amount of halothane required was small. Heart and respiratory rates decreased (p<0.001) but remained within the normal range. Rectal temperature was above normal at the time of sedation and at the time of blood sampling when the ambient temperature was 29° C but not when the ambient temperature was reduced to 25°C. CONCLUSIONS: The combination of medetomidine, butorphanol and atropine at these doses produced sedation of variable depth and duration that was insufficient on its own to allow blood sampling in the majority of pigs. Hyperthermia can occur in temperature-controlled environments when using medetomidine, butorphanol and atropine in pigs. Reduction of stress and a quieter environment may improve the effects of the anaesthetic combination. 相似文献
139.
The distribution in 1953 and the habits of the two squirrelsSciurus vulgaris leucourus and S. carolinensis are discussedand their control considered. 相似文献
140.
THE EFFECT OF PHOSPHATE APPLICATIONS ON THE DIFFUSION COEFFICIENTS AND AVAILABLE PHOSPHATE IN AN ACID SOIL 总被引:1,自引:0,他引:1
The apparent bulk phosphate self-diffusion coefficient, resin extractable and isotopically exchangeable phosphate were measured on an acid Cecil sandy loam soil pre-treated with calcium carbonate and monocalcium phosphate. Apparent diffusion coefficients increased four-fold with a five-fold increase in phosphate addition, but were not increased by liming. Resin extractable phosphate was greater than isotopically exchangeable after large phosphate additions. Calculated porous self-diffusion coefficients did not change as a result of phosphate additions. The contribution of solid-phase phosphate to diffusion was small and close to the limits of measurement. 相似文献