单株选择提高小麦品系贵农001品质的研究

特定的条件下远缘杂交育成的品种（系），在较大的群体中进行某几个性状的定向选择，可以育成新需性状的小麦品种。在形态特征基本一致和高分子量麦谷蛋白优质亚基组成基本纯合的小麦品种（系）中进行单株选择，能够筛选出湿面筋含量显著提高的类型和亚基组成更优的类型。     

植物育种的株选技术方法研究

结合豇豆育种实践阐述了植物育种中株选的重要性和目的、株选的策略和株选方法等。笔者新提出了改良加权评分法和同工酶辅助株选法。认为（1）通过对易观察、遗传力高且与育种目标相关性大的性状选择可尽快实现育种目标。（2）把各性状看作灰选性状，单株级别则视为灰选等级，根据灰选等级进行株选，以各经济性状与产量的灰色关联度作为各性状的权重，计算得到各单株综合评价值，确定等级标准值，并划分等级结果，变权重主观赋值为客观求值，有利于提高株选的准确性和效率（3）利用同工酶生化标记辅助株选，可克服株选中仅从表现型出发而导致的偏差，也有利于改变过去只有在品种选育成功后，才研究其生化或遗传基础，藉此可大大缩短育种年限。本研究可资豇豆育种利用和其他植物育种借鉴。     

双向偏心受压基础底面尺寸直接计算法

本文给出了柱下基础双向偏心受压时基底尺寸的直接计算公式。可较快地求得充分利用地基承载能力、经济合理的基础底面积。     

Imazapyr and Triclopyr Tank Mixtures for Basal Bark Control of Woody Brush in the Southeastern United States

Small diameter woody brush on forestlands and rights-of-way can be controlled with a basal bark application of either triclopyr or imazapyr. The purpose of this study is to evaluate the efficacy of triclopyr and imazapyr tank mixtures for a variety of rates and species. Imazapyr at the standard rate of 19 g ae/l does not have the broad-spectrum control of triclopyr at the standard rate of 96 g ae/l. Test mixtures adding various rates of imazapyr to the standard rate of triclopyr provided no significant benefit. This study documents effective basal spray treatments for 15 of 16 test species. Only eastern redcedar proved difficult to control.     

Stand growth scenarios for Tectona grandis plantations in Costa Rica

Management scenarios with rotation lengths of 20 and 30 years were developed for different site qualities (high, medium and low) under two different management options (high individual tree growth versus high stand growth) for teak (Tectona grandis L.f.) in Costa Rica. The scenarios are based on data collected in different regions in Costa Rica, representing different site conditions, offering a variety of possible management options for high-quality teak yield.

Three competition indices were used for modeling the competition and for the definition of intensities and the plantation age at thinning. The maximum site occupation (MSO) and the Reineke density index (RDI) provide conservative stand density management limits, resulting in the need to execute several thinning frequently. The competition factor (CF) matches the field observations and seems to be more appropriate for the growth characteristics of the species.

Final stand densities varied between 120 and 447 trees ha⁻¹, with mean diameter at breast height (dbh) of 24.9–47.8 cm, and mean total heights between 23.0 and 32.4 m, depending on rotation length and site quality. The mean annual increment of total volume (MAI_Vol) at the end of the rotation varied from 11.3 to 24.9 m³ ha⁻¹ year⁻¹, accumulating a total volume over rotation of 268–524 m³ ha⁻¹.

The most suitable scenario for teak plantations for high-quality sites is the 30-year-rotation scenario with five thinnings of intensities between 20 and 50% (of the standing trees) at the ages of 4, 8, 12, 18 and 24 years. After the sectioning of the merchantable stem in 4-m length logs, the merchantable volume varied between 145 and 386 m³ ha⁻¹, with an estimated heartwood volume of 45–195 m³ ha⁻¹, both depending on rotation length and site quality.     

STR基因座在奶牛个体识别中的应用

通过分析2份冷冻精液样本和4头可疑种公牛血样的BM1862、BM2113、BM720和TGLA122 STR基因座遗传多样性,旨在判断该2份冷冻精液的种公牛来源,为建立奶牛个识别方法奠定基础。结果表明,应用STR基因座对个体进行识别,鉴别能力达0.9999。说明四个STR基因座可以用于冻精质量监测或奶牛个体识别和亲子鉴定。     

河蟹仔蟹管道式饲养初步研究

采用封闭式的蜂窝状塑料管道作为蟹穴，对河蟹仔蟹进行两个月的饲养观察试验，每隔１５ｄ测定一次壳长、壳宽和体重，用数理统计方法分析了河蟹的个体生长特点，比较了蟹穴饲养和非蟹穴饲养以及不同形式的蟹穴饲养效果。结果表明，仔蟹的个体生长为跳跃式的非连续增长。蟹穴饲养对河蟹的壳长、壳宽和体重的生长无不利影响，而增重率明显优于散养，且Ｌ型蟹穴的生长效果比Ｉ型蟹穴要好     

黑龙江垦区户养奶牛适度规模的初探

通过对黑龙江垦区个体奶牛户的经验规模、最低规模和优化规模研究，确定了适度经营规模：个体养奶牛以10头为宜．在此规模下可获得较好的经济效益．     

火炬松,湿地松抗松枯梢病,松针褐斑病种源和个体选择的研究

南京老山林场火炬松、湿地松种源试验林在１０ａ生时（１９９１年）开始感染松枯梢病和松针褐斑病,病情日趋严重,在１３ａ生（１９９４年）和１５ａ生（１９９６年）时两次重复测定感病和生长变异,火炬松不同种源感病和生长变异均极显著,两者间及年度间相关极显著。按照选择指数的大小选出抗病、生长优良种源４个即９号（佛罗里达·纳索）,１０号（路易斯安那·利文斯通）,１２号（阿拉巴马·埃尔卡拉）和１９号（佐治亚·爱克特）,其选择指数比平均值大２１．４３％～４８．１０％,感病指数低３３．７１％～４９．５３％,树高大７．３２％～１３．５２％,胸径大７．５０％～１７．１９％。同时选出两年重复测定均优良的单株４０多株（占总株数６．７％左右,其中优良种源占５０％）,其感病级别０～Ⅰ级,生长量比平均值大１０％以上。湿地松种源间感病变异不显著,生长虽然有一定变异,但两者相关不显著。选择主要在个体间进行。已选出并经两年重复测定均优良的单株２０多株（占总株数３．３％左右）,其感病级别为０～Ⅰ级,生长量比平均值大１０％以上。     

单氰胺对休眠及其解除中葡萄多酚和多酚代谢酶及不同部位单体酚含量的影响

研究单氰胺处理下葡萄休眠冬芽总酚含量和PPO、PAL活性的变化,并利用高效液相色谱切换波长法对休眠打破过程中葡萄冬芽和1 a生枝条韧皮部和木质部中6种单体酚的变化进行考察。结果表明,葡萄休眠过程中,随着低温的积累,PPO、PAL活性和酚类物质总量均增加,PAL活性和总酚量在休眠解除过程中均降低且变化趋势基本一致,但降幅有限,从整体上看PPO在萌芽后仍旧维持较高活性。单氰胺处理后与对照差异不大。在黑比诺葡萄休眠打破过程中,韧皮部中除白藜芦醇外,没食子酸、原儿茶酸、儿茶素、表儿茶素、没食子酸酯均呈上升趋势;木质部中的没食子酸、原儿茶酸和表儿茶素呈上升趋势,白藜芦醇呈下降趋势,儿茶素呈“W”型,表儿茶素、没食子酸酯无明显变化规律;冬芽中没食子酸和儿茶素的变化呈上升趋势,原儿茶酸、表儿茶素、没食子酸酯、白藜芦醇均呈下降趋势,且其中的原儿茶酸、表儿茶素和没食子酸酯在临近萌芽的一段时间内含量基本不变,萌芽后含量迅速下降。初步判定没食子酸可能对休眠解除起促进作用,白藜芦醇可能对休眠解除起抑制作用。