杉木种子园中无性系间结实和种子品质差异研究

在观察的31个无性系中丰产的约占20％,产量约占总产30％;中等的占60％弱,产量占54％;低产的占20％强,产量约占17％。结实的广义遗传力hw~2平均0.66。不同无性系在雌雄花比、雌花序结构、球果大小和分枝稠密度等方面存在差异。一般植株“偏雌性”、聚生雌花序占优势,球果大、树冠表面积大而分枝稠密的无性系结实量高;反之,“偏雄性”、单生雌花序为主、球果小、树冠表面积小而分枝稀疏的无性系结实量低。据72个无性系的分析,大粒种子无性系约占21％,中粒的约占47％,小粒的占32％;高发芽率无性系占23.6％,中发芽率的占57％,低发芽率的占19.4％。大粒种子无性系的发芽卒往往高于中、小粒种子无性系;而发芽势有相反趋势。     

蚕豆百粒重遗传变异及改良研究

利用青海蚕豆品种和外来超大粒品种杂交,分析了蚕豆百粒重遗传变异及改良效果,结果表明:百粒重在F1代表现为中间型,有时表现为超亲优势,有时表现为没有优势,这与亲本之间籽粒大小以及母系遗传有关,在选择改良百粒重的杂交亲本时,充分考虑育种目标。同时,利用籽粒大小差异较大的亲本选配组合,F2代群体百粒重分离较大,对蚕豆品种的籽粒大小改良效果较好。     

水稻生长中期群体结构对产量及构成因素的影响

对 8个基肥施氮比例及数量所形成的水稻抽穗期群体结构与产量及构成因素的研究表明 :①水稻抽穗期群体茎鞘重 /叶重比值、茎蘖数、单茎重及倒 3叶长、比叶重、剑叶长决定成熟期产量的 96.0 2 %。②成熟期有效穗主要受抽穗期群体茎蘖数、茎鞘重 /叶重比值及比叶重影响 ;穗总粒数主要受比叶重、茎鞘重 /叶重比值、倒 2叶长及茎蘖数影响 ;穗实粒数主要受茎鞘重 /叶重比值、比叶重、茎蘖数影响 ;千粒重主要受比叶重影响 ,但不显著。③促使穗期群体形成适量的茎蘖数并提高茎鞘重 /叶重比值 ,将作为改进施肥及管理技术的主要依据。④适宜施氮量的 70 %～ 80 %作基肥深施 ,其余作穗肥补施 ,能促使水稻抽穗前形成源库优化型群体而提高产量     

热处理对单叶省藤材化学成分及颜色的影响

为了研究高温热处理温度和保温时间对棕榈藤材化学成分和颜色的影响及二者之间的相关性,以单叶省藤(Calamus simplicifolius)为对象,研究了常压蒸汽高温热处理温度(160、180、200℃)与处理时间(2、4 h)对单叶省藤材的化学成分、质量损失率及颜色的影响,分析了热处理后材色与化学成分变化的相关性。结果表明:随着热处理温度的升高和热处理时间的延长,单叶省藤材的质量损失率呈逐渐升高的趋势,在200℃、4 h时,藤材质量损失率达到最大,综纤维素和纤维素质量分数呈下降的趋势,木质素和苯醇提取物呈相对升高的趋势。热处理过程中藤材化学成分的质量分数变化对材色改变有很大影响,热处理后藤材的明度差、总体色差与综纤维素质量分数差、纤维素质量分数差和木质素质量分数差都有较好的线性相关性。     

土壤磁化率-温度(κ-T)曲线测定中的影响因素研究

土壤磁化率-温度曲线(κ-T)可用于鉴定土壤中磁性矿物类型。以水稻土、红壤、黄壤和砖红壤为对象,采用BaringtonMS2κ-T磁化率/温度系统,测定了不同土壤类型中磁性矿物种类。结果表明:水稻土κ-T曲线在300℃出现矿物相变点,黄壤、红壤和砖红壤在350℃出现相变点;水稻土和黄壤κ-T曲线呈现出磁铁矿的居里点(580℃),表明土壤磁性载体以磁铁矿为主;红壤和砖红壤的κ-T曲线呈现赤铁矿的居里点(680℃)。将水稻土和红壤分别制成2 mm、1 mm、0.30mm和0.15 mm的颗粒大小,称取相同质量土样(1 g)研究不同颗粒大小对土壤κ-T曲线测定的影响;称取过2 mm筛土样0.5 g、1 g、1.5 g和2 g,研究不同称样量对κ-T曲线测定的影响。结果表明:不同土壤类型,颗粒大小和称样量对κ-T曲线的测定有一定影响,但不会改变土壤中磁性矿物的相变点。它们对红壤和砖红壤的κ-T曲线测定影响甚少,对水稻土和黄壤的影响较大。实验证明在颗粒大小上选择过0.30 mm筛的土样,称样量上选择大于1 g的土样可以得到较明显的κ-T曲线,不会掩盖矿物的相变点。     

Fruit thinning in ‘Conference’ pear grown under deficit irrigation: Implications for fruit quality at harvest and after cold storage

Fruit thinning in pear is feasible for mitigation of water stress effects. However, it is not well known how fruit quality at harvest and after cold storage is affected by pre-harvest water stress. Even less is known about the effects of fruit thinning on quality under these circumstances. To elucidate these, we applied deficit irrigation (DI) and fruit thinning treatments to ‘Conference’ pear over the growing seasons of 2008 and 2009. At the onset of Stage II (80 and 67 days before harvest in 2008 and 2009, respectively), two irrigation treatments were applied: full irrigation (FI) and DI. FI trees received 100% of crop evapotranspiration (ETc). DI trees received no irrigation during the first three weeks of Stage II to induce water stress, but then received 20% of ETc to ensure tree survival. From bud-break until the onset of Stage II and during post-harvest, FI and DI trees received 100% of ETc. Each irrigation treatment received two thinning levels: no thinning leaving commercial crop load (∼180 fruits tree⁻¹), and hand-thinning at the onset of Stage II leaving a light crop load (∼85 fruits tree⁻¹). Under commercial crop loads, DI trees were moderately water-stressed and this had some positive effects on fruit quality. DI increased fruit firmness (FF), soluble solids concentrations (SSC) and acidity at harvest while no changes were observed in fruit maturity (based on ethylene production). Differences in FF and acidity at harvest between FI and DI fruit were maintained during cold storage. DI also reduced fruit weight loss during storage. But fruit size was reduced under DI. Fruit thinning under DI resulted in better fruit composition with no detrimental effect on fresh-market yield compared to un-thinned fruit. Fruit size at harvest and SSC values after five months of cold storage were higher in fruit from thinned trees than fruit from un-thinned trees. Fruit thinning increased fruit ethylene production, indicating advanced maturity. This may lead to earlier harvest which is desirable in years with impending drought. Fruit thinning is therefore a useful technique to enhance pear marketability under water shortage.     

武定鸡快慢羽纯系及其杂种鸡早期肉用性能的测定

 用武定鸡快、慢羽两个纯系,以及以武慢羽为母本分别与武快羽和红布罗快羽为父本交配,测定快、慢羽对早期肉用性能的影响,结果:由同一来源分离出的快、慢羽纯系、公母混合试验组中,虽在1-90日龄生长速度和屠体重,快羽高于慢羽,但无显着差异.而在以武慢羽为母本的两个自别雌雄配套组合中,公母分开饲养,同一组合公母间的体重及屠体重虽有差异.但不显着.不同组合以及两个纯系间,不论公母,除屠宰率,全净膛率等相对数无显着差异外,都表现出以红布罗快羽为父本的组合.其活重和屠体重极显着地大于其它各组.初步证明以红布罗快羽为父系、武慢羽为母系、生产能自别雌雄接近土鸡毛色的肉仔鸡,是开发利用武农Ⅰ系的一条有效途径.     

鸡蛋图像检测方法与质量预测模型

首先利用牛顿二分法快速识别鸡蛋图像边缘信息;然后通过边缘信息简化图像区域面积像素和公式及图像形心坐标公式,提出自动确定长轴的方法;最后建立了鸡蛋蛋形指数和质量的预测模型。验证结果表明,边缘检测效率提高了大约20倍;实际蛋形指数与预测指数的相关程度达到0.9523;通过图像面积像素和与图像旋转体积像素和所预测的质量与实际质量的相关性达到0.9806。     

Optimum manufacturing conditions of activated carbon fiber absorbents. I. Effect of flame retardant reagent concentration

In this paper, viscose rayon-based knitted fabrics were utilized as the precursor to produce activated carbon fiber absorbents (ACFA). To obtain better pore characteristics and higher weight yield of ACFA, the effect of flame retardant reagent concentration was studied. Experimental results revealed that both BET surface area and micropore volume increased with increasing flame retardant reagent concentration. On the other hand, both weight yield and micropore volume ratio (V_mic/V_tot) decreased as the flame retardant reagent concentration increased. It was therefore concluded that controlling the flame retardant reagent concentration at 30% not only could obtain better absorption property of ACFA but also helped maintain its production efficiency.