Photosynthate Unloading from Seed Coats of Phaseolus vulgaris L. an Attempt to Define Conditions Required for Stimulation by Abscisic Acid and Benzylamino Purine     

John W.PATRICK 《浙江大学学报(农业与生命科学版)》1990,(4)

The instablity of the stimulation of photosynthate unloading from seed coats of Phaseolus vulgaris by abscisic acid (ABA ) and benzylamino purine ( BAP ) was studied in terms of experimental conditions. ABA stimulated photosynthate unloading at pH 6 and pH 8 without close dependence upon pH. ABA at a concentration range of 10-5-10-4 mol/L displayed stimulatory effect. However, BAP revealed no effect at a concentration range of 10-6-10-4 mol/L. Experiments designed with different transport time of 14C-photosynthate indicated that ABA might act at the plasma membrane of the unloading cells. Reducing endogenous ABA level by diminishing leaf area did not facilitate the manifestation of exogenous ABA function. Potassium ion stimulated photosynthate unloading from seed coats with highest promotion at 100 mmol/L K . However, no dependence of ABA stimulation of photosynthate unloading on K was found.  相似文献   

Effect of oak (Quercus persica) acorn level on apparent digestibility,ruminal fermentation,nitrogen balance and urinary purine derivatives in pregnant goats          下载免费PDF全文

H. Jafari  F. Fatahnia  A. Khatibjoo  G. Taasoli  H. Fazaeli  S. Varmaghany 《Journal of animal physiology and animal nutrition》2018,102(4):882-891

The aim of this experiment was to investigate the effect of dietary oak (Quercus persica) acorn (OA) level on dry matter intake (DMI), apparent nutrient digestibility, nitrogen (N) utilization, ruminal fermentation, protozoa population and urinary purine derivatives (PD) during the last 60 days of goat pregnancy. Twenty‐four multiparous pregnant goats (41.7 ± 2.3 kg BW) were assigned to one of three experimental diets consisted of control diet (C, without OA) and diets containing 20 (OA₂₀) or 40 g/100 g of OA (OA₄₀) on a DM basis in a completely randomized block design. Goats fed OA₄₀ had lower DMI (p < .01), DM (p < .01), OM (p < .01) and NDF (p < .05) digestibility, ruminal NH₃‐N concentration (p < .01), N intake (p < .01) and N retention (p < .01). Crude protein digestibility and ruminal acetate and total volatile fatty acid (VFA) concentration were lower in animals fed OA‐contained diets (p < .01), whereas ruminal propionate concentration was higher in goats fed the C diet (p < .01). Animals fed OA₄₀ had higher faecal N excretion and lower urinary N excretion (p < .01). Urinary PD was lower in goats fed diets containing OA in relation to those fed the C diet (p < .01). Total protozoa population decreased linearly with increasing OA level in the diet (p < .05). These results suggest that feeding OA, especially high level, has negative impacts on DMI, nutrient digestibility, VFA concentration, N retention and urinary PD excretion that may have adverse effects on metabolism and performance of pregnant goats.  相似文献   

肾型传染性支气管炎病毒对鸡嘌呤代谢的影响研究   总被引：1，自引：0，他引：1  

马跃  田晋红  张晓瑜  李小姝  刘爱国  张祖梅  冉毅 《中兽医医药杂志》2005,24(6):21-23

用T株肾型传染性支气管炎病毒(IBV)人工感染14日龄非免疫土种鸡建立感染模型,于攻毒前、攻毒后48 h、72 h、96 h、120 h 采集血样,测定血浆黄嘌呤氧化酶(xanthine oxidase, XOD)活性,探索鸡嘌呤代谢变化与肾型IBV致病机理之间的关系.结果表明,与攻毒前相比较, 攻毒后48 h和72 h血浆XOD活性明显增强, 差异显著(P<0.01,P<0.05).结果提示,XOD活性升高引起的嘌呤代谢紊乱可能是鸡肾型IB的病理机制之一.  相似文献   

The effect of exogenous purine supply on the endogenous excretion of purine derivatives in the urine of growing lambs     

Tsutomu FUJIHARA  Martin N. SHEM  Tohru MATSUI 《Animal Science Journal》2006,77(6):582-586

An experiment was made to determine the absorption of purine metabolites in dietary nucleic acids through the digestive tract, and also to determine the utilization of nucleic acids absorbed in the body, using growing lambs. Two pairs of 120‐ and 180‐day‐old twin female lambs with a bodyweight of 18.2–19.0 kg were kept in metabolism crates and fed on purine‐free milk replacement (MR) with supplements of exogenous purine (purine base or purine nucleoside) at a level of 0.2 mmol/BW^0.75/d for 5 consecutive days, and thereafter they were maintained in the crates for 4 days. The daily amount of exogenous purine supply was calculated based on the urinary excreted purine derivatives (PD) in lambs fed on milk replacement alone. A urine sample was collected daily for 9 consecutive days, and the urinary excretion of PD was determined daily. Urinary PD excretion opened to increase within 24 h after the dose of purine bases, and the level was recovered on 3 days after ceasing the exogenous purine supply. The recovery of PD in the urine was about 70% of the purine supplement. When purine nucleosides were added to the feed, urinary PD excretion was initiated within 24 h after dosing, and the values were recovered after ending the purine nucleoside supply. The recovery rate of PD in the urine was only 30% of the supplemented purine. The plasma allantoin levels were almost similar after feeding purine bases and purine nucleosides, and the values were mostly in the range (40–60 µmol/L). These findings indicate that an exogenous purine can be directly incorporated into the body, and the purine as nucleoside is more effectively utilized for the synthesis of nucleic acids than as a purine base in the body of growing lambs.  相似文献   

异戊酸对西门塔尔牛瘤胃发酵及尿嘌呤衍生物的影响   总被引：2，自引：0，他引：2  

刘强  黄应祥  王聪  王浩  郭刚 《畜牧兽医学报》2007,38(2):155-160

选用4头体重(420±8.6)kg,年龄2.5岁装有永久性瘤胃瘘管的中国西门塔尔牛阉牛,采用4×4拉丁方设计,以混合精料和玉米秸秆为基础日粮,研究异戊酸(0、0.02、0.04和0.06 g/kgW)对瘤胃pH、NH3-N、VFA、营养物质降解率及尿嘌呤衍生物浓度的影响。结果表明:0.06 g/kgW组显著降低瘤胃pH(P<0.05),饲喂后3-6 h,0.04 g/kgW组和0.06 g/kgW组NH3-N浓度显著低于对照和0.02 g/kgW组(P<0.05);0.04 g/kgW组和0.06 g/kgW组,豆粕干物质、有机物质和粗蛋白质有效降解率显著低于对照(P<0.05);0.04 g/kgW组玉米秸秆干物质、有机物质、中性洗涤纤维和酸性洗涤纤维的有效降解率显著提高(P<0.05),0.04 g/kgW组瘤胃乙酸、丁酸、乙酸/丙酸比例、总挥发性脂肪酸和尿嘌呤衍生物显著增加(P<0.05)。异戊酸的适宜添加水平为0.04g/kgW。  相似文献   

不同比例香根草日粮对沼泽性水牛尿嘌呤衍生物排出量的影响   总被引：1，自引：1，他引：0  

钟伟  龙瑞军  J. B.Liang  T. Jetana 《甘肃农业大学学报》2007,42(1):25-29

试验采用4×4拉丁方设计,利用4头18月龄,体质量为(262±17.9)kg处于生长期的泰国沼泽性水牛,通过饲喂粗料中4种不同比例香根草的日粮,观察每单位可消化有机物质尿嘌呤衍生物排泄量(PD/DOMI)的变化,来研究不同日粮对水牛尿嘌呤衍生物(PD)排出量的影响.结果表明,随着香根草在粗料中比例的增大,尿囊素(Allantoin)、尿酸(Uric acid)及总嘌呤衍生物(total PD)的排出量都增加,且日粮间差异显著(P<0.05),而黄嘌呤和次黄嘌呤(Xan-thine+hypoxanthine)的排出量在各个日粮间差异不显著(P>0.05);PD/DOMI随着日粮中香根草含量的增加,在日粮间差异不显著(P>0.05).研究说明香根草占粗料50%时,对水牛尿嘌呤衍生物(PD)的排泄量影响最大(PD的排出量:17.5 mmol/d,PD/DOMI:6.11 mmol/kg).  相似文献   

肉牛混合日粮不同进食水平对尿中嘌呤衍生物排出量的影响     

王永新  莫放  董宽虎  黄应祥  高登宏  陈瑶 《勤云标准版测试》2008,(12)

为研究肉牛不同进食水平对尿中嘌呤衍生物(PD)排出量的影响,试验选用4头当地黄牛按4×4拉丁方设计进行两期消化代谢试验,两个试验的日粮由精料和粗料由40:60(试验1)和60:40(试验2)组成,试验日粮分别按"自由采食量"的100%、80%、60%和40%饲喂4种相同组分不同进食量的日粮,用全收粪法和全收尿法分别测定有机物(OM)的消化率和尿中PD排出量,试验结果表明,日粮进食水平对全消化道OM表观消化率没有明显影响(P>0.05),尿中PD排出量随进食水平提高而增加(P<0.05),而尿中肌酸酐的排出量没有明显差异(P>0.05),尿中PD排出量可以用来估测瘤胃微生物蛋白质产生量。  相似文献   

Impaired purine biosynthesis affects pathogenicity of <Emphasis Type="Italic">Fusarium oxysporum</Emphasis> f. sp. <Emphasis Type="Italic">melonis</Emphasis>     

Youlia?Denisov  Oded?Yarden  Stanley?FreemanEmail author 《European journal of plant pathology / European Foundation for Plant Pathology》2005,112(3):293-297

The vascular wilt pathogen Fusarium oxysporum f. sp. melonis causes worldwide yield losses of muskmelon. In this study, we characterized a UV-induced non-pathogenic mutant (strain 4/4) of F. oxysporum f. sp. melonis, previously identified as a potential biological control agent. During comparative analysis of vegetative growth parameters using different carbon sources, mutant strain 4/4 showed a delay in development and secretion of extracellular enzymes, compared to the wild type strain. Amendments of the growth medium with yeast extract, adenine or hypoxanthine, but not guanine, complemented the growth defect of strain 4/4, as well as secretion and partial activity of cellulases and endopolygalacturonases, indicating that the strain is an adenine auxotroph. Incubation of strain 4/4 conidia in adenine solution, prior to inoculation of muskmelon plants, partially restored pathogenicity to the mutant strain.  相似文献   

Propagation in vitro of pear, Pyrus communis L., cultivars ‘William's Bon Chrétien’, ‘Packham's Triumph’ and ‘Beurré Bosc’     

Xiao-Shan Shen  M.G. Mullins 《Scientia Horticulturae》1984,23(1):51-57

Shoot cultures were established from nodal explants of 3 pear cultivars by subculture on Murashige and Skoog medium containing mixtures of 3 cytokinins. Zeatin and 6·(γ,γ-dimethylallylamino)purine were both supplied at 10 μM and benzyladenine as follows: ‘William's Bon Chrétien’, 6 μM; ‘Packham's Triumph’, 8 μM; ‘Beurré Bosc’, 10 μM. Production of axillary shoots was greater by basal explants (4–6) comprising the remnants of the previous subculture than by apical explants (2–3) comprising the distal parts of extension shoots. Up to 80% of microcuttings of all cultivars formed roots in vitro with either γ-indolebutyric acid, 10 μM, or α-naphthaleneacetic acid, 10 μM, and approximately 50% of rooted microcuttings were successfully established as container-grown plants. Use of aseptic methods for producing own-rooted pears is discussed in relation to fruit growing and fruit improvement.  相似文献   

饲粮不同采食水平下肉羊氮沉积和尿中嘌呤衍生物排出规律的研究     

马涛  刁其玉  邓凯东  姜成钢  屠焰  王永超  刘洁  赵一广 《动物营养学报》2012,24(7):1229-1235

本试验旨在研究饲粮不同采食水平下肉羊氮沉积和尿中嘌呤衍生物(PD)的排出规律.试验选用12只平均体重为(41.3±2.8)kg的杜寒杂交绵羊公羔,随机平均分为3组,按照自由采食、自由采食量的70％和自由采食量的40％3个干物质采食水平饲喂,试验期为12d,其中预试期7d,正试期5d.结果表明:随着饲粮采食水平的降低,营养物质消化率均显著上升(P＜0.05),粪氮和尿氮排出量均显著降低(P＜0.05),沉积氮与摄入氮之间存在线性相关(R2=0.92).尿中PD排出量和微生物氮(MN)产量均随采食水平的降低而显著降低(P＜0.05),嘌呤氮指数(PNI)与氮沉积率和氮吸收率均表现出相同变化趋势.由此可见,PD排出量与可消化有机物采食量(DOMI)以及MN产量之间均存在线性相关,相关方程分别为y=21.41X-1.81(R2=0.94)和Y=0.91X+2.57(R2=0.94);PNI能够将氮平衡和PD排出量有机结合起来,用于评价饲粮氮的利用效率.  相似文献