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1.
苜蓿传粉特性及其制约种子产量形成的因素分析   总被引：21，自引：4，他引：17  
采用传粉生物学的方法,对"新牧1号"杂花苜蓿Medicago lupulina的花朵酬物、花粉特性、访花者种类、访花行为、访花频率、传粉效果等方面进行了观测,并对种子生产中导致低产的原因进行了分析.结果显示:1)每花有花粉(3 509.3±299.12)粒,产蜜0.1～0.5μL/d,持续3～5 d.单花9:30-10:30开始泌蜜,16:00-18:00达到泌蜜高峰.2)花粉败育率为(40.48±2.33)%;新鲜花粉活力(51.87±2.08)%,在室温下放置7 d后,活力降至25.39%;自然状态下每花柱头上有花粉(36.20±2.12)粒,P/O(花粉数/胚珠数)值为(288.73±32.01).3)初花期及盛花初期约有访花昆虫5种.在10 m2小区内,平均每天拜访25.33次,拜访花序17.67个;在标记的10个花序中,未观察到拜访昆虫.盛花期约有访花昆虫15种.在10 m2小区内,平均每天拜访187次,拜访花序1 083个;在标记的10个花序中,平均每天每花序被拜访2.1次.4)从传粉效果看:初花期及盛花初期开放的花序,结荚率为(16.45±2.91)%,荚内种子数(3.91±0.34)粒;盛花期开放的花序,结荚率为(83.32±1.31)%,荚内种子数(5.12±0.25)粒.上述结果表明:在传粉过程中,苜蓿花朵酬物少、花粉败育率高、昆虫传粉效率低是导致其种子产量低下的主要因素之一.  相似文献   

2.
采用3因素二次饱和-D最优设计方法，研究多年生人工草地栽培措施与生产性能之间的关系，通过测定播种密度、叶面喷施“常乐”益植素日期、播种行距3因素条件下试验的各项参数，建立不同播种密度、不同叶面喷施“常乐”益植素日期、不同播种行距对高寒牧区多叶老芒麦地上部分牧草产量、种子产量关系的函数模型：y1=3．43＋0、177x1＋0．133x2＋0．097x3＋0．024x1x2＋0．06x1x3-0．02x2x3＋0．168x1^2-0．1x2^2-0、22x3^2，y2=49．6＋1．2x1-1．9x2＋2．2x3＋3．3x1x2＋3．1x1x3＋73x，x-7．7x1^2-6．9x^2，-4.9x3^2,并提出高寒牧区多叶老芒麦高产的农艺措施，即播种密度411-929株丛／平方米、播种行距24～31cm、叶面喷施“常乐”益植素日期6月12日～7月5日。  相似文献   

3.
建立了血液中蓖麻碱残留量的高效液相色谱（HPLC）检测法。用三氯甲烷提取蓖麻碱，除去蛋白质和脂肪后，用HPLC法对其进行测定。采用Hypersil ODSC C18色谱柱（250mm×4．6mm，25μm），水-乙腈（9：1，V/V）为流动相，流速0．8mL／min，检测波长为220nm。结果显示，在0．26—5．2μg范围内，蓖麻碱峰面积与质量的线性关系良好，回归方程为y=1．57×10^4 x-4．93×10^5，r=0．999，RSD=3．82％。牛血中蓖麻碱平均回收率为72．1％，RSD为2．54％（n=5）。饲喂蓖麻粕的牛血液中蓖麻碱的含量为0．512μg／mL。  相似文献   

4.
叶面喷硼对紫云英结实特性的影响   总被引：2，自引：0，他引：2  
硼是植物生长发育所必需的微量元素,与植物的细胞与功能、花粉管发育伸长以及对光合作用的产物-碳水化合物的合成与转运有重要作用。本研究通过开花前叶面喷施硼肥,探讨硼肥对紫云英花荚结实成粒的调控效应,以期为增加紫云英籽粒数、提高种子产量调控技术应用提供参考。选取“信紫1号”为供试材料,在开花前叶面喷施清水(对照CK)、硼肥[500 (T1)、1000 (T2)、2000 (T3)、4000 (T4)、6000 mg·L-1(T5)]。在成熟期,按常规考种法记载单位面积株数、分枝数、不同层花序的花序数、结荚数、籽粒数等指标。结果表明,各喷施浓度处理(除T3处理外)的单位面积花序数、结荚数、单荚籽粒数和荚果结实率在不同层花序上与对照间差异均不明显。喷施浓度T3处理的单位面积花序数在第3~6层花序上较对照分别提高31.87%、40.79%、37.49%和44.99%,单位面积结荚数较对照分别提高27.89%、32.69%、35.92%和25.84%,单荚籽粒数较对照分别提高20.69%、23.54%、23.24%和22.03%,荚果结实率较对照分别增加2.95%、2.56%、3.49%和4.51%,然而在第1和2层花序上与对照差异不明显。进一步分析产量构成发现,喷施不同浓度硼肥处理对紫云英单位面积有效株数、一级分枝数、单株一级分枝数和千粒重影响不大。综上,在紫云英花荚脱落开始之前叶面喷施2000 mg·L-1硼肥,可显著促进第3~6层花序单位面积花序数、结荚数和单荚籽粒数的增加,从而促进荚果结实率的提高,最终获得较高的种子产量。  相似文献   

5.
王浆高产蜜蜂和意大利蜜蜂工蜂蛹期生长发育研究   总被引：1，自引：0，他引：1  
通过比较王浆高产蜜蜂（Apis mellifera L,浆蜂）和意大利蜜蜂（Apis mellifera L）工蜂蛹期的生长发育过程,结果发现浆蜂和意蜂的工蜂蛹体重和头重随着日龄的增长均极显著降低（p〈0．001）;各日龄浆蜂工蜂蛹的体重和头重均极显著高于意蜂蛹体重和头重（P〈0．001）;浆蜂工蜂蛹体重随日龄变化回归曲线为：y=69．85555＋11．7309x-0．4261x^2,决定系数R^2=9975;意蜂工蜂蛹体重随日龄变化回归曲线为：y=75．3093＋9．5603x-0．36069x^2,决定系数R^2=0．9951;浆蜂工蜂蛹头重随日龄变化回归曲线为：y=52．4847＋104846x-0．3564x^2,决定系数R^2=0．9964;意蜂工蜂蛹头重随日龄变化回归曲线为：y=55．9616＋10．6083x-03547x^2,决定系数R^2=0．9948。由此可见：（1）浆蜂虽然经过多年选育产浆性状发生了变化,但是工蜂蛹期生长发育曲线与意蜂基本吻合;（2）各日龄浆蜂工蜂蛹期头重均显著高于意蜂,这可能是浆蜂产浆量提高后,头部分泌王浆的腺体产生变化所引起的。  相似文献   

6.
赵梦雨  王斌  王腾飞  兰剑 《草业科学》2023,(11):2871-2878
为探讨宁夏半干旱区紫花苜蓿(Medicaco sativa)种子田高效生产的最佳播种量，采用单因素随机区组设计，研究不同播种量(S1:1.2 kg·hm-2,S2:1.8 kg·hm-2,S3:2.4 kg·hm-2,S4:3.0 kg·hm-2,S5:3.6 kg·hm-2)对紫花苜蓿种子生产性能和构成因素的影响。结果表明，播种量对紫花苜蓿株高、一级分枝数、每生殖枝花序数、每花序小花数、每花序结荚数、单位面积生殖枝条、每荚种子数、千粒重、实际种子产量和表现种子产量均有显著影响(P <0.05)，其中单位面积生殖枝数、每生殖枝花序数、每花序结荚数、每荚种子数及千粒重均在S4播量下达到最高，分别为177.09、23.35、12.56、6.16和1.88 g；株高和每花序小花数在S2播量下达到最大，分别为87.81 cm和1...  相似文献   

7.
本试验建立了丙酮中苯残留的气相色谱检测方法。采用氢火焰离子检测器,设定程序升温,初温45℃,以6.5℃/min的升温速率升至100℃保持10 min,以外标法计算含量。苯含量在0.04~0.24μg/m L范围内与峰面积具有良好的线性关系,线性方程为y=1 141.6x-1.78,相关系数R2为0.999,检测限为0.02 mg/L,定量限为0.07 mg/L,专属性和回收试验符合要求。该方法简便、灵敏、准确,适用于丙酮中苯的测定。  相似文献   

8.
俄罗斯紫花苜蓿主根圆锥状,茎直立或斜升,有细小柔毛,深绿色。小叶卵圆形,叶色中等。荚果单螺旋形、双螺旋形。每荚种子平均数为7．6粒。种子肾形,黄色或黄褐色。千粒重为2．159g。抗寒性强,产草量高。行距为0．7m、株距为0．25m、穴播量为3．0kg／hm2时表现种子产量为1067．6kg/hm2。  相似文献   

9.
通过对盛世紫花苜蓿自繁种与引进种进行对比栽培，结果表明，在亚热带海拔1590m的四川凉山安宁河坝区盛世紫花苜蓿春季可正常开花、结荚、产种，种子成熟期植株高度在62.0cm以上；总分枝数、单株分枝数自繁种比引进种高；单株总花序数及结荚花序数和三、四级总花序数及结荚花序数自繁种分别为165．19、92．04、98．63、55．37个，引进种相应为64.22、31．89、35．59、17．04个，差异显著（P〈0．05）；每个花序结英数、每个荚结子粒数及饱满子粒数自繁种分别为12，39个、5，40粒、2．33粒，引进种13．22个、5-41粒、2．48粒，差异不显著（P〉0．05）；单株产种量自繁种1．35g，小区产种量11．35g/m^2，折合每公顷产种量113．55kg，引进种相应为1．35g，10．45g/m^2，折合每公顷104．55kg，差异不显著（P〉0．05）；千粒重自繁种2．58g，引进种2．54g。  相似文献   

10.
用HPLC法同时测定氯胺酮、地西泮血药浓度及药代动力学。流动相:乙腈∶水(用Na3PO4调pH≈10)=1∶1(V/V),紫外检测波长:UV=230 nm;流量:0.6 mL/min,建立测定条件。绘制标准曲线,地西泮回归方程为y=1 873.4x-9 421,R2=0.999 6,在0.25～8μg/mL范围内呈现良好的线性关系;氯胺酮回归方程为y=75 586x-25 286;R2=0.999 5,在1～32μg/mL范围内呈现良好的线性关系。单次静脉给药后,分别于0、5、10、20、40及60 min测定血药浓度,并计算两者药代动力学参数。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
Tropical Animal Health and Production -  相似文献   

14.
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   

15.
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   

16.
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   

17.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

18.
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   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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