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991.
宁凝  杨世海 《人参研究》2013,25(2):20-22
目的探讨不同因子对黄秋葵毛状根生长的影响。方法利用增殖倍数法测定毛状根的生长.从而明确各因子对黄秋葵毛状根的影响。结果3%蔗糖浓度最适宜毛状根的生长。0.5mg/L6-BA对毛状根有一定的抑制作用,0.5mg/LNAA、IAA对毛状根有一定的促进作用。尤其是0.5mg/LIAA培养的毛状根增殖倍数更为显著。MJA对毛状根生长有抑制作用,SA对毛状根的生长没有明显的影响。结论不同因子不同程度地影响了毛状根的生长,为进一步筛选适宜的黄秋葵毛状根培养体系奠定了基础。  相似文献   
992.
陶萌春  马慧 《热带作物学报》2012,33(10):1886-1889
以不同种源、不同萌发时期的朱砂根幼苗为研究对象,建立同时测定朱砂根幼苗中赤霉素(GA3)、生长素(IAA)两种内源激素的高效液相色谱(HPLC)条件。结果表明:采用Phenomenex Luna C18反相柱(5μm,250 mm×4.6 mm),甲醇和水(含0.6%乙酸)为流动相,体积比45∶55,等度洗脱,流速1.0 mL/min,柱温25℃,在波长254 nm下检测,GA3和IAA的分离效果理想,线性关系良好,回收率分别达到89.5%和87.3%。整个过程简单、易操作。比较了野生种源与栽培种源朱砂根不同苗龄期的GA3和IAA含量变化,野生种源幼苗GA3和IAA的含量较高。  相似文献   
993.
以两类不同株型梨品种(系)为试材,研究了紧凑型与普通型梨一年生嫁接苗的形态特征、生长发育特点、内源激素含量变化及15 a生树新梢的解剖结构。结果表明,与普通型相比,紧凑型嫩梢中脱落酸(ABA)和赤霉素(GA3)含量显著较少,细胞分裂素(ZR及Z+ZR)含量显著较多,生长素(IAA)含量稍高于普通型但差异不显著。紧凑型新梢顶端木薄壁细胞显著增加,导管、木质纤维和可溶性糖显著减少。首次提出确定梨紧凑型基本指标为新梢顶端木质部中木质纤维密度低于1 300个.mm-2,木薄壁细胞密度高于1 700个.mm-2,导管密度低于270个.mm-2;紧凑型梨树节间变短可能是赤霉素(GA3)含量减少引起的,顶端的膨大生长等现象则可能是细胞分裂素积累引起的。  相似文献   
994.
L. Lahaye  Y. Riou  B. Sve 《Livestock Science》2007,109(1-3):138-140
Two experiments were performed in order to test the effects of grinding and pelleting wheat (experiment 1) or maize (experiment 2) on amino acids (AA) standardized (SID) and true (TID) ileal digestibility. Basal ileal endogenous losses (IEL), used to calculate SID from apparent digestibility, were determined by feeding a protein-free diet. Total IEL required to calculate TID were estimated as the difference between total and dietary losses determined according to the isotope dilution technique using 15N-labeled crops. Wheat and maize were ground to compare two different mean particle sizes (d50 500 μm and 1000 μm). Then, a fraction of the 500-μm mash was further pelleted through two dies of different thicknesses (16 vs. 20 mm for wheat and 16 vs. 24 mm for maize), holes diameter 4 mm in both cases. Cereals were incorporated in 4 isoproteic diets either in mash form (fine vs. coarse mash) or in pelleted form (thin vs. thick die). In experiment 1, wheat was associated with rapeseed meal diets, while in experiment 2, maize was associated with soybean meal. The reduction of wheat particle size affected neither AA SID nor TID. In contrast, the pelleting treatment significantly improved protein and most AA SID and TID. In addition, total IEL of protein and several AA were significantly reduced when the thicker die was used. Numeric improvements of protein and AA SID were observed with reduction of maize particle size and this was associated with a significant decrease in total IEL so that TID was not modified. Further improvements of AA SID and TID occurred with pelleting of maize, without significant effect on IEL regardless of die thickness.  相似文献   
995.
In veal calf production plant-based proteins are frequently included in milk replacer fed to the animals. Since soy products, which are mostly used, are known for their high levels of phyto-oestrogens, the effects of these feeds on the veal calf prostate were examined. Goal was to determine whether these compounds could interfere with histological screening for oestrogenic growth promoters. In a feeding experiment, four groups of veal calves fed plant-based protein-supplemented milk replacer (PBM), containing 5% soy concentrate, 5% soy isolate, 5% wheat gluten and 2% potato protein, for 4 weeks were compared to animals fed dairy-based control feed (DBM); animals treated with estradiol benzoate, diethylstilbestrol and ethinylestradiol served as positive controls. Daidzein and genistein levels measured in feed and urine showed high levels of genistein and daidzein in the soy isolate and soy concentrate supplemented feeds. Genistein and daidzein were also found in the urine of the animals that were fed these feeds. Haematoxylin–eosin-stained prostate sections of PBM-fed animals showed slight hyperplasia and some dilated tubules as compared to the DBM-fed group, but no metaplasia, which is used for screening for oestrogenic hormones. The positive controls showed extensive squamous metaplasia. Immunohistochemical staining for cytokeratin 5 (using RCK 103 monoclonal antibody) in basal cells showed a normal staining pattern of basal cells in the DBM-fed calves and extensive basal cell proliferation and squamous metaplasia in the oestrogen-treated positive control animals. PBM-fed calves showed no increase of basal cell staining but showed elongations of the basal cells in most animals, sometimes resulting in circular figures. It is concluded that the feeds examined in this study did not interfere with histological screening for oestrogens in male veal calves.  相似文献   
996.
以新疆棉区主栽品种新陆早33号和新彩棉7号为实验材料,比较不同激素组合对两者体细胞胚胎发生过程的影响,以建立高效再生体系。结果表明,新陆早33号和新彩棉7号在2,4-D+KT的激素组合下出愈率均为100%,降低2,4-D浓度有利于胚性愈伤组织的分化,分化率分别达到60.0%和7.5%;在IBA+KT的激素组合下出愈情况相对较差,分别为72.5%和85.0%;继代几次后,两个品种的胚性愈伤组织分化率可分别达到45%和55%,新陆早33号和新彩棉7号分别在DK和IK激素组合下更有利于体细胞胚胎发生过程。进一步观察发现,新彩棉7号分化形成胚状体的能力比新陆早33号更强,两品种均能在6个月内获得再生植株。再生体系的建立,为新疆棉花开展分子育种工作奠定了基础。  相似文献   
997.
998.
The aim of this study was to examine possible effects of bee pollen added to the feed mixture (FM) on rat ovarian functions (secretion activity and apoptosis). We evaluated the bee pollen effect on the release of insulin‐like growth factor I (IGF‐I) and steroid hormones (progesterone and estradiol), as well as on the expression of markers of apoptosis (Bcl‐2, Bax and caspase‐3) in rat ovarian fragments. Female rats (n = 15) were fed during 90 days by FM without or with rape seed bee pollen in dose either 3 kg/1000 kg FM or 5 kg/1000 kg FM. Fragments of ovaries isolated from rats of each group (totally 72 pieces) were incubated for 24 h. Hormonal secretion into the culture medium was detected by RIA. The markers of apoptosis were evaluated by Western blotting. It was observed that IGF‐I release by rat ovarian fragments was significantly (p < 0.05) decreased; on the other hand, progesterone and estradiol secretion was increased after bee pollen treatment at dose 5 kg/1000 kg FM but not at 3 kg/1000 FM. Accumulation of Bcl‐2 was increased by bee pollen added at 3 kg/1000 kg FM, but not at higher dose. Accumulation of Bax was increased in ovaries of rats fed by bee pollen at doses either 3 or 5 kg/1000 kg FM, whilst accumulation of caspase‐3 increased after feeding with bee pollen at dose 5 kg/1000 kg FM, but not at 3 kg/1000 kg FM. Our results contribute to new insights regarding the effect of bee pollen on both secretion activity (release of growth factor IGF‐I and steroid hormones progesterone and estradiol) and apoptosis (anti‐ and pro‐apoptotic markers Bcl‐2, Bax and caspase‐3). Bee pollen is shown to be a potent regulator of rat ovarian functions.  相似文献   
999.
以彩色马蹄莲品种"Picasso"种球为试验材料,研究其开花过程中种球营养物质和内源激素含量变化。结果表明:从种植到开花,种球中蛋白质和淀粉的含量迅速下降,开花后含量回升;而可溶性总糖在开花阶段处于较高值,开花后下降;淀粉酶活性较高时,淀粉含量较低,开花后淀粉酶活性明显降低,而此时种球内淀粉含量迅速升高。各激素含量在种植的不同阶段出现不同的变化趋势,IAA含量在营养生长期和盛花期较高;ZR含量在种植至开花,一直处于较高值,有利于种球开花,开花后ZR含量降低;GA在开花期间含量较高,而开花后GA含量不断下降,促进种球膨大和休眠;ABA含量在前90d缓慢下降,进入开花后期含量缓慢上升。  相似文献   
1000.
为明确在低温下茄子脱落酸(ABA)、生长素(IAA)、赤霉素(GA3)、玉米素(ZT)质量分数的变化规律,选取耐低温性不同的6份材料,进行低温弱光处理,前2d内白天15℃,夜间10℃,光照度4000lx;然后白天10℃,夜间7℃,光照度4000lx,再连续处理10 d.结果表明,在常温下各内源激素的质量分数差异不显著,经低温处理后ABA,IAA,GA3含量上升,ZT含量下降,差异达显著水平.相关分析表明,茄子的耐低温性与低温处理后的ABA,IAA质量分数的偏相关均呈显著正相关;与GA3含量,ZT含量的偏相关均呈正相关,未达显著水平.说明低温使茄子幼苗的生长受到一定程度的抑制,但能够通过调节自身的内源激素来减轻低温的伤害,维持植物体的正常生长及生理代谢功能,从而表现出一定的耐低温潜力.  相似文献   
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