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1.
不同处理方法对美国截叶胡枝子种子发芽的影响   总被引:2,自引:0,他引:2  
美国截叶胡枝子的硬实率很高,发芽率只有17.3%。经过种子预处理,如采用不同温度下浸种、98%浓硫酸浸泡、机械破皮和机械破皮结合热水浸种等处理,结果表明,机械破皮后用60℃热水浸种处理的效果最好,发芽势和发芽率分别达到64.0%和74.3%;其次是机械破皮,平均发芽率达到50%;浓硫酸浸种可以显著提高种子发芽势,浓硫酸浸种5min效果最好,发芽率达到44.7%;热水浸种的处理效果不佳,最好的90℃热水浸种处理发芽率也仅有26.7%。  相似文献   

2.
美国截叶胡枝子的硬实率很高,发芽率只有17.3%.经过种子预处理,如采用不同温度下浸种、98%浓硫酸浸泡、机械破皮和机械破皮结合热水浸种等处理,结果表明,机械破皮后用60℃热水浸种处理的效果最好,发芽势和发芽率分别达到64.0%和74.3%;其次是机械破皮,平均发芽率达到50%;浓硫酸浸种可以显著提高种子发芽势,浓硫酸浸种5min效果最好,发芽率达到44.7%;热水浸种的处理效果不佳,最好的90℃热水浸种处理发芽率也仅有26.7%.  相似文献   

3.
以白刺花种子为材料,分别采用砂纸摩擦,30%NaOH浸种0.5、1、1.5、2、2.5、3h,90%NaOH浸种5、15、25、35、45、55min,98%浓硫酸浸种10、20、30、40、50min对种子进行硬实处理,在室温(25~28℃)下进行发芽试验。结果表明:砂擦处理效果最好,发芽率为80%;98%浓硫酸处理...  相似文献   

4.
本研究以“腾格里”牛枝子(Lespedeza potaninii Vass.)种子为试验材料,研究了不同的处理方法对去除宿存萼片和破除种子硬实的影响,旨在明确牛枝子种子去除宿存萼片和破除硬实的方法。结果表明:种子破皮机处理4遍和浓硫酸处理12 min时,宿存萼片全部去除;所有处理均能显著提高种子发芽率、发芽势、发芽指数和活力指数,降低硬实率(P<0.05);种子破皮机在处理9遍时,发芽率最高(66.33%),发芽势、发芽指数和活力指数也较高;浓硫酸处理20~30 min,发芽率最高在80.00%以上,发芽势、发芽指数和活力指数也较高。综上所述,由于浓硫酸是一种具有高腐蚀性的强矿物酸,属于危险化学品,生产中操作存在安全风险,而种子破皮机处理4遍可以完全去除宿存萼片,将种子处理9遍可以有效降低硬实率,发芽率可达60.00%以上,且操作方便和安全,易于规模化处理,建议在牛枝子种子生产中推广应用。  相似文献   

5.
不同处理方法对3种豆科灌木种子发芽率的影响   总被引:10,自引:4,他引:6  
采用不同的化学试剂对多花木蓝,紫穗槐和胡枝子3种灌木的种子进行处理,测定其发芽势和发芽率。结果表明,不同处理下发芽率的差异达极显著水平(P<0.01)。其中,多花木蓝的种子,以浓硫酸浸泡15 min和100 g/L硝酸钾溶液浸泡6 h的处理最好,发芽率在72%以上;紫穗槐经浓硫酸浸泡15 min,平均发芽率在76%以上;胡枝子则以30%的双氧水浸泡30 min最好,发芽率为72.7%。因此,选用适宜的方法处理种子,可降低种子硬实率,打破休眠,从而提高种子发芽率。  相似文献   

6.
敖汉苜蓿硬实种子处理方法研究   总被引:10,自引:0,他引:10  
试验以2002年收获的敖汉苜蓿种子为材料,采用不同水温浸种、98%浓硫酸不同浸种时间和石英砂磨破种皮等处理来研究打破敖汉苜蓿种子硬实的效果。结果表明,浓硫酸浸种处理中效果最佳的是浸种60 min,平均发芽率达到99%;不同水温浸种处理中效果最佳的是75℃的热水处理,平均发芽率达到79%。3种处理中以98%浓硫酸浸种60 min的效果最好,其次是石英砂磨破种皮,而各种水温浸种的效果较差。  相似文献   

7.
试验以2002年收获的敖汉苜蓿种子为材料,采用不同水温浸种、98%浓硫酸不同浸种时间和石英砂磨破种皮等处理来研究打破敖汉苜蓿种子硬实的效果.结果表明,浓硫酸浸种处理中效果最佳的是浸种60 min,平均发芽率达到99%;不同水温浸种处理中效果最佳的是75 ℃的热水处理,平均发芽率达到79%.3种处理中以98%浓硫酸浸种60 min的效果最好,其次是石英砂磨破种皮,而各种水温浸种的效果较差.  相似文献   

8.
浸种处理对闽引羽叶决明种子萌发的影响   总被引:5,自引:1,他引:4  
研究了温水、98%硫酸浸种对闽引羽叶决明种子萌发的影响,结果表明,未浸种闽引羽叶决明种子硬实率达87.7%,初始温度100℃温水浸种5~30 min,种子硬实率降至9.7%~13.0%,种子发芽率、发芽势分别上升至87.0%~90.3%和85.0%~88.0%,发芽指数达48.2~56.5,明显优于其他温水浸种处理。98%硫酸浸种10 min,种子硬实率低于2.0%,种子发芽率、发芽势和发芽指数最高,分别为98.3%,97.3%和87.0%。  相似文献   

9.
多花木蓝种子硬实与萌发特性研究   总被引:1,自引:0,他引:1  
通过不同方法时多花木蓝种子进行处理,测定了吸水率、发芽率、发芽指数和活力指数。结果表明,不同处理对提高多花木蓝发芽率的效果差异达极显著水平(P〈0.01)。采用98%浓硫酸浸种时间分别为1、2、3、4、5、6、7、8、9、10min处理中,以6min处理效果最好,发芽率达95%;采用60qC热水浸种时间分别为5、10、15、20、25、30、35min处理中,以25min处理的效果最好,发芽率为71.6%。  相似文献   

10.
浸种处理对圆叶决明种子萌发的影响   总被引:1,自引:0,他引:1  
摘要:为寻求圆叶决明(Chamaecrista rotundifolia)种子硬实破除技术,开展热水和硫酸浸种处理对2个圆叶决明品种种子萌发的影响试验。结果表明,未浸种条件下闽引圆叶决明、闽引2号圆叶决明种子硬实率分别达56.3%、76.0%。初始温度为100 ℃热水浸种3 min,闽引圆叶决明种子硬实率降至11.7%,发芽率升至42.7%,发芽指数达32.1,高于其他热水浸种处理。不同热水浸种处理闽引2号圆叶决明的种子硬实率无显著差异。98%硫酸浸种10 min,闽引圆叶决明、闽引2号圆叶决明的种子硬实率分别降至1.3%、0,而且发芽指数均达峰值,分别为58.9、37.0,相应的发芽率分别为64.7%、80.0%。  相似文献   

11.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

12.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

13.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

14.
15.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

16.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

17.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

18.
19.
An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.  相似文献   

20.
Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein  相似文献   

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