玉米秸秆拉伸特性的试验研究

该文利用二次正交旋转组合试验设计方案,深入研究了含水率、叶鞘位置和取样位置3个因素对玉米秸秆拉伸特性的综合影响。结果表明,含水率和取样位置的单因素效应对玉米秸秆的拉伸特性有显著影响,而叶鞘位置基本上不影响拉伸特性。此外,含水率和取样位置的交互作用对拉伸特性也有显著的影响,且随着玉米秸秆样品的取样位置的不断升高,顶部和底部的秸秆样品的最大拉伸载荷和抗拉强度的变化与含水率的变化截然相反,可能是因为不同位置的秸秆有着不同特性的内部组织结构。该研究为玉米秸秆机械化收获装备的设计提供依据。     

木薯遗传图谱16号连锁群与其细胞学图谱的整合

利用荧光原位PCR技术体系整合木薯的分子遗传图谱,将16号连锁群上的NS376和SSRY86标记定位到华南6号木薯的染色体上,结果表明:这2个标记均能在华南6号不同时期的细胞上检测到1个信号.结合核型分析,将NS376标记定位在华南6号的第4号染色体的短臂上,扩增位点到着丝粒的百分距离是31.25,将SSRY86标记定位在第4号染色体的长臂上,扩增位点到着丝粒的百分距离是75.86.NS376和SSRY86 2个标记位于木薯的同一对染色体上,并且分别位于该染色体的两端,进一步揭示了16号连锁群对应的是木薯的4号染色体.     

芥蓝产量性状QTL定位

芥蓝的丰产性状是育种的重要目标性状,由于控制芥蓝的产量性状均为数量性状,常规育种进展缓慢,基因定位及分子标记辅助育种可提高选择效率。本研究利用2个产量差异大的芥蓝自交不亲和系冬强♀（产量高）与Lb07M（产量低）为亲本,构建F2分离群体,F2自交获得F2 ∶ 3家系,对产量性状进行了QTL定位分析。对F2 ∶ 3家系中单株重、单薹重、株高、薹高、叶长、叶宽、薹粗进行了调查,利用已构建首张芥蓝变种内的SSR和SRAP遗传图谱,结合田间性状调查数据,用QTLNetwork2.0软件通过混合线性复合区间作图法（MCIM）对7个产量性状进行了QTL分析。在10个连锁群中共定位了8个QTL位点,其中控制单薹重、单株重、株高、叶宽的QTL各1个,分别解释表型变异的18.4％,17.8％,19.1％,15.1％;控制主薹高和叶长的QTL各为2个,共解释表型变异的23.8％、22.1％。芥蓝产量性状的QTL定位结果可为分子标记辅助选择高产品种提供参考。     

不同产地黄芩中黄芩苷含量的对比研究

目的：对不同产地黄芩中的黄芩苷含量进行比较研究。方法：用高效液相色谱法,测定不同产地（河北承德、山西岚县）黄芩中黄芩苷的含量。结果：河北承德产黄芩中黄芩苷含量为302.547 mg/g,山西岚县产黄芩中黄芩苷的含量为246.588 mg/g,经配对t检验分析,结果表明t=21459.30,显著因子Sig.=0.001〈0.01,组间均值差异极显著,这两地产黄芩中黄芩苷含量差异极显著。结论：以黄芩苷含量为考察指标,河北承德产黄芩要优于山西岚县产黄芩。     

Morphological variation in Dutch perennial ryegrass (Lolium perenne L.) populations,in relation to environmental factors

Summary Twenty-one Dutch Lolium perenne populations, fifteen European populations and six L. perenne cultivars were compared for morphological variation. Dutch populations clearly differed from the European populations and the cultivars. Dutch populations generally had reduced plant length and smaller leaves. For other characters, e.g. date of ear emergence, the Dutch populations showed as much variation as the European populations and cultivars they were compared with in this trial. Correlations between morphology and environmental factors at the site of origin were significant in several cases but were generally weak, and dependent on the set of populations studied. In order to maximize the phenotypic differences between the collected populations, soil type and management type appeared to be the most important factors for the choice of collection sites in the Netherlands. To determine suitable collection sites all over Europe, other factors like precipitation, latitude, altitude and temperature factors were also important. For subsampling of the locations, variation in management type within the location determined whether or not phenotypic different samples could be collected. The extensive use of cultivars in the Netherlands does not seem to have prevented the formation of distinct populations. Therefore in situ conservation of grassland seems a good alternative for genetic conservation of L. perenne in the Netherlands.Also associated with the WAU Department of Plant Taxonomy, P.O. Box 8010, 6700 ED, Wageningen, The Netherlands     

Phytase activity, phytate, iron, and zinc contents in wheat pearling fractions and their variation across production locations

Pearling is an effective method for evaluating the distribution of chemical components in wheat grain. Twelve pearling fractions (P₁–P₁₂) of wheat grain were obtained using two rice polishers for 10 cultivars (six soft red wheats and four hard white wheats) grown at two locations with different environmental conditions in Jiangsu Province, China. The results show that the effects of cultivar, location, and pearling on wheat flour phytase activity, phytate, iron, and zinc contents were all significant, with pearling having the greatest effect. All the four components showed a diminishing trend as pearling progressed from the outer layers to the inner part of wheat grain. Generally, the P₂ fraction (the outer 4–8% layer of wheat grain) had the highest phytase activity and phytate and iron contents, whereas the P₁ fraction (the outer 0–4% layer) ranked the highest for zinc content. Growing location had a large influence on grain phytase, phytate, and iron, but the differences between locations decreased as pearling level increased.     

不同产地厚朴种子性状的变异分析

厚朴(Magnolia officinalis Rehd. et Wils.)为木兰科(Magnoliaceae)落叶乔木.正品药用厚朴为厚朴的根皮、干皮和枝皮,其中的有效成分(厚朴酚(magnolol)、和厚朴酚(honokiol)及β-桉叶油醇等)具有多方面的药理作用(如燥湿消痰、下气除满),用于湿滞伤中、脱痞吐泻、食积气滞、腹胀便秘、痰饮喘咳等[1-4].厚朴主要分布于102NFA48122°E、22NFA4834°N之间,分布区内的不同气候及土壤条件,致使形成大量不同的遗传类型,其中种子形态必然存在很大的差异.     

云岭牛不同解剖部位肉品质评价

为了明确云岭牛不同解剖部位肉的品质特性,本试验测定了云岭牛冈上肌（SU）、冈下肌（IF）、臀三头肌（TB）、菱形肌（RH）、颈腹侧锯肌（SVC）、夹肌（SP）,中部胴体的腰大肌（PM）、背最长肌（LD）、背阔肌（LA）,后部胴体的半膜肌（SM）、半腱肌（ST）、股二头肌（BF）、臀中肌（GM）、股直肌（RF）、股外侧肌（VL）和阔筋膜张肌（TFL）共16个解剖部位肉的压力失水率、蒸煮损失、剪切力、pH、亮度（L^*）、红度（a^*）、黄度（b^*）、粗蛋白质、脂肪、水分10项品质指标,并通过方差分析、相关性分析和标准化分析研究其品质特性。结果显示,云岭牛不同解剖部位肉之间的10项品质指标均存在显著差异（P<0.05）。冈上肌、冈下肌、腰大肌、颈腹侧锯肌和阔筋膜张肌的嫩度较好,其剪切力均低于4 kg。夹肌、半腱肌和股外侧肌的保水性较差,半腱肌的L^*值最高。相关性分析结果表明,剪切力和压力失水率、蒸煮损失呈显著正相关。标准化分析发现,背最长肌和半腱肌具有相似的品质特征;股二头肌、臀中肌和股外侧肌具有相似的品质特征。结果表明,部位因素对云岭牛肉品质具有显著影响,云岭牛胴体前部肉品质较好,可以作为开发高档产品的原料来源。     

棉花品种区域试验适宜试验点数量的抽样估计

 基于长江流域国家棉花区域试验的对照品种泗棉3号、湘杂棉2号、湘杂棉8号和鄂杂棉10号在2000－2011年期间84～270次试验中早熟性、农艺性状、产量性状和纤维品质性状表现,构建了对照品种抽样总体,采用随机抽样方法估计了在不同精确度水平下鉴别棉花品种主要性状表现所需要的试验点数量,旨在为长江流域棉区国家棉花区域试验的试验点数量设置提供理论依据,并为其它棉区乃至其它作物区域试验中适宜试验点数量的估计提供参考方法。研究结果表明：试验点数量的需求与目的性状选择及变异度密切相关,皮棉产量的表型标准差最高,在同等精确度水平下需要的试点数量也最多。目前,长江流域棉花区域试验设置18个试点,对皮棉产量的估计精确度为90%;增加16个试点,估计精确度将提高到93%;而随后再增加试点数量对提高估计精确度收效甚微。