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61.
“中苜一号”紫花苜蓿耐盐遗传特性初步研究   总被引:4,自引:1,他引:4  
杨青川  苏加楷 《草地学报》1998,6(3):162-170
以“中苜号”紫花苜蓿耐盐新品种为材料,应用NCⅡ杂交试验方案,研究其耐盐遗传参数,旨在为今后苜蓿耐盐育种提供理论依据。结果表明,在直 迫下,苜蓿的干重、株高和分枝数诸性状的加性产应大于显性效应,狭义跗力较大,分别为0.425、0.387和0.484,具有通过选择进一步提高耐盐性的遗传潜力。  相似文献   
62.
本试验旨在比较高原蕨麻小型猪与平原巴马小型猪的血液生理生化指标差异,为高原蕨麻小型猪的实验动物化提供理论基础.试验分别在高原地区和西安市采集高原蕨麻小型猪与巴马小型猪血样,检测10项血液生理指标和14项血液生化指标,并对结果进行统计分析.结果显示,血液生理指标中高原蕨麻小型猪的红细胞计数(RBC)、血红蛋白(HGB)、红细胞压积(HCT)、红细胞平均血红蛋白含量(MCH)、红细胞平均血红蛋白浓度(MCMH)均极显著高于巴马小型猪(P< 0.01),血小板(PLT)、红细胞分布列宽变异系数(RDW-CV)和红细胞分布宽度标准差(RDW-SD)与巴马小型猪相比差异显著(P< 0.05);血液生化指标中高原蕨麻小型猪γ-谷氨酰基转移酶(GGT)、葡萄糖(GLU)、肌酐(CRE)均极显著高于巴马小型猪(P< 0.01),其余指标均无显著差异(P> 0.05).结果表明,高原蕨麻小型猪具有低氧适应的生理特征,与巴马小型猪相比有独特的高原适应性,具有开发成为高原疾病动物模型的潜力.  相似文献   
63.
本研究通过提前叶片采样时期,运用诊断施肥综合法(DRIS)对不同产量水平红富士苹果进行了叶片矿质营养诊断,以期为早期红富士苹果营养诊断与科学施肥提供依据.测定诊断结果表明,渭北旱塬红富士苹果叶片N、P、K、Ca、Mg、Cu、Fe、Mn、Zn的适宜值分别为26.04±3.50 g·kg-1、2.84+0.74 g·kg-1、15.05±4.08 g·kg-1、14.25±3.04 g·kg-1、3.15±0.73 g·kg-1、12.69±3.14 mg· kg-1、262.87±82.05 mg·kg-1、96.33±33.35 mg·kg-1、23.57±10.13 mg·kg-1.选择的DRIS诊断参数中,除N/Zn、Cu/P、P/Zn、Ca/Zn、Mg/Zn和Cu/Zn外,30种表示形式的变异系数均表现出低产组(< 25 kg·tree-1)大于高产组(<25 kg·tree-1);高产组和低产组的养分不平衡指数(NII)分别为73和88.相对于高产组,低产组元素间关系更不平衡.总体而言,渭北旱塬区红富士苹果园除产量高于41.3kg· tree-需肥顺序排在第一位的元素为Cu外,其它均为P;需肥顺序排在第二位的元素高产为K,低产果园仅当产量低于10.2 kg·tree-1时为K,其余为Zn;而排在第三位的,高产均为Ca,低产均为Mg.  相似文献   
64.
The aim of this investigation is to compare the physicochemical properties and chemical composition of Phoenix canariensis seed oil at different stages of seed date ripening. It was demonstrated that the saponification number of the oil increases during the maturation from 179.24 to 191.28 (mg KOH/g of oil), whereas the seed oil yield, the iodine number, the p-anisidine value, the peroxide value, the acidity and the unsaponifiable matter decrease from 14.73% to 10.36%, from 89.37 to 76.66 (g/100 g of oil), from 5.51 to 3.67, from 17.66 to 3.62 (mequiv. O2/kg of oil), from 1.49% to 0.59% and from 2.72% to 1.77%, respectively. The tocol content increases as the maturity advanced. The percentages of sterols show continuous changes during ripening. The saturated fatty acid content increases throughout the ripening process. The oleic fatty acid content decreases during the seeds maturation, but increases at the end, whereas linoleic acid content initially shows an increase, and then a decrease. The total phosphorus content decreases during the period of ripening. The three samples of the seed oil show a high kinetic stability during the heating and cooling, as characterised by the differential scanning calorimetry (DSC). The DSC curves reveal an increase in the melting point from −7.73 °C to 3.71 °C but the melting enthalpy remains the same, 62.06 J/g, during the ripening of the dates.  相似文献   
65.
转基因小麦抗旱性鉴定及相关指标灰色关联度分析   总被引:1,自引:0,他引:1  
以9份转ABP9基因春小麦株系UC4-1~UC4-9及其受体亲本宁春4号为材料,在雨养和灌溉条件下,对这些材料的主要农艺性状和部分生化指标进行了测定,采用隶属函数值法和抗旱性度量(D)值法对其抗旱性进行了综合评价,并利用灰色关联度法对相关抗旱性状与抗旱指数之间的关联度进行了分析评价。结果表明:6份转基因小麦的抗旱性较受体亲本宁春4号增强,3份材料的抗旱性较非转基因春小麦品种定西35增强;各农艺性状和生化指标与抗旱指数的关联度从高到低依次分别为株高、单穗粒重、穗长、SOD活性、穗粒数、结实小穗数、有效分蘖数、POD活性、千粒重、脯氨酸含量、MDA含量。  相似文献   
66.
Eight trained horses (6 mares – 2 geldings, 6 Selle Français, 2 Trotteur Français, 12 ± 5.8 years old, 538 ± 72.5 kg) were offered three diets to potentially affect haematology and the fatty acids (FA) profiles in red blood cells (RBC) membranes. The control diet was composed of 50% hay and 50% concentrate containing mainly rolled barley (48%) and whole spelt (48%). In the case of sunflower oil diet, sunflower oil (62.0% of α‐linoleic acid, LA) was incorporated at a rate of 8% and substituted by an equal proportion of barley. In the linseed oil diet, first cold‐pressed linseed oil (56.0% of α‐linolenic acid, ALA) was utilised at a similar incorporation rate of 8%. The experimental design consisted of three 3 × 3 latin squares with one being incomplete. Each period lasted 8 weeks. On average, the total feed intake (straw excluded) was 6.2 kg/day and the oil intake 0.278 kg/day. The oils significantly increased the concentrations of RBC, haemoglobin and haematocrit. The oils had no significant impact on the haematology profiles except that platelets tended to decrease in both oil‐based diets. The most abundant FA in the RBC membranes of the control diet samples were in the decreasing order LA, C18:1n9‐7, C18:0, C16:0 and the arachidonic acid (ARA) respectively. The sunflower oil supplementation slightly increased the amount of LA (36.23 vs. 34.72 mg/dl, p = 0.55) and C22:4n‐6 (0.21 vs. 0.09 mg/dl, p = 0.22), while the decrease was observed in case of other FA (C16:1n‐7, 1.08 vs. 1.42 mg/dl, p = 0.03), C20:3n‐6 (0.22 vs. 0.31 mg/dl, p = 0.02), and ARA (1.17 vs. 1.63 mg/dl, p = 0.08). Linseed oil induced similar effects in the n‐6 series FA profiles. In the context of practical applications, our results show that linseed oil incorporation in the diet could improve the haematology and the n‐3 FA profiles potentially leading to an increased performance.  相似文献   
67.
为探讨返青期休牧对退化高寒草地植被特征及优势种光合生理的影响,本研究在祁连山区选择已实施返青期休牧6年的高寒草甸开展了植被特征及优势种光合生理相关指标的调查研究.结果表明:返青期休牧6年后,高寒草甸的植被盖度、地上生物量、地下生物量和土壤含水量较未休牧区分别增加了38.44%,985.00%,209.56%和62.62...  相似文献   
68.
为探讨不同浓度重金属Pb2+胁迫对绢毛委陵菜(Potentilla sericea L.>)光合特性及荧光参数的影响,本文采用盆栽的方法,通过对绢毛委陵菜净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)、胞间CO2浓度(Ci)等多项指标的测定,并对其变化规律做了比较研究。结果表明:绢毛委陵菜胞间CO2浓度(Ci)随Pb2+胁迫时间的延长及胁迫浓度的增大呈上升趋势,而净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)变化趋势与胞间CO2浓度(Ci)变化趋势相反;Pb2+胁迫50 d时PSⅡ潜在活性(Fv/Fo)、最大光化学效率(Fv/Fm)均随胁迫浓度的增大逐渐降低;绢毛委陵菜在Pb2+浓度为300 mg·kg-1、600 mg·kg-1时能够生存,但生长缓慢。研究表明随着铅浓度的提高,铅通过影响植物的非气孔限制来影响绢毛委陵菜的光合特性。  相似文献   
69.
the objective of the study was to develop and evaluate different breeding objectives for sow productivity and for production traits, using economic selection indices. Genetic parameters were generated using a repeated records model for sow productivity traits and a maternal effects model for production traits, in ASREML. Stochastic simulation models based on a hypothetical 100-sow model were performed for each line, i.e., a dam line and a terminal sire line, respectively, to derive economic values. The traits included in the study were number born alive (NBA), 21-day litter size (D21LS), 21-day litter weight (D21LWT), average daily gain (ADG), feed conversion ratio (FCR), age at slaughter (AGES), dressing percentage (DRESS), lean content (LEAN) and backfat thickness (BFAT). The economic values for LEAN and BFAT were derived using the partial differentiation of the profit function, while those for the other traits were derived using the partial budget approach. An economic value of a trait was the change in profit per unit genetic change in that trait. Breeding objectives were developed with a corresponding selection index, for improvement of that objective. Three combinations of breeding objectives and selection indices were developed for sow productivity traits, while there were 15 combinations for production traits. Responses to selection and economic return were computed for each combination to determine the most appropriate combination for the improvement of the breeding objective traits. The most appropriate index to improve sow productivity consisted of NBA and D21LWT. For production traits, the combination that consisted of a selection index with AGES, DRESS and BFAT, and the breeding objective ADG, DRESS, FCR and LEAN, was considered the most appropriate. Age at slaughter and BFAT were, respectively, included as indicator traits for ADG and LEAN. The recommended breeding objectives were sensitive to changes in economic values, indicating that economic values for breeding goal traits should be updated periodically to ensure proper weighting of traits, hence maximization of economic return.  相似文献   
70.
本试验旨在通过在断奶仔猪饲粮中添加银杏防御素,研究其对仔猪生长性能及免疫指标的影响,以期为生产上提供安全、环保、高效的绿色饲料添加剂.试验选择断奶后体重约为7 kg的“杜×长×大”仔猪120头,随机分为对照组和试验组,每组5个重复,每个重复12头猪.对照组饲喂基础饲粮,试验组饲喂在基础饲粮中添加0.2%银杏防御素的试验饲粮.试验期21 d.结果显示,与对照组相比,试验组末重提高了8.92%(P <0.05),腹泻率极显著降低(P<0.01),料重比降低了7.27%(P <0.05);血清免疫球蛋白G、免疫球蛋白M、免疫球蛋白A含量分别提高了13.03%(P <0.05)、12.27%(P <0.05)、7.89%(P >0.05),血清白蛋白和总蛋白含量分别提高了19.97%(P <0.05)和14.97%(P <0.05),血液T淋巴细胞转化率提高了8.25%(P >0.05),血液白细胞介素2含量提高了15.25%(P <0.01).由此可见,银杏防御素可提高仔猪生长性能和免疫指标,降低腹泻率.  相似文献   
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