丰产剂2号蘸花对番茄果实各部位糖分及淀粉含量的影响

研究了丰产剂2号蘸花对不同发育期番茄果实单果质量、果实各部位糖分组成和含量及淀粉含量的影响。结果表明:丰产剂2号蘸花明显提高单果质量;在番茄果实各发育期,丰产剂2号蘸花的果实各部位糖分组成和含量的总体变化趋势与对照基本相同,果柄维管束中主要含蔗糖,果实其他部位主要含果糖和葡萄糖,果糖和葡萄糖含量在成熟时达到最高;但丰产剂2号蘸花处理的果实中果糖和葡萄糖含量增幅高于对照,说明丰产剂2号蘸花处理可以全面提高番茄果实中可溶性糖的含量。而丰产剂2号蘸花处理对淀粉含量的影响不明显。     

新疆棉区日最低气温对棉纤维次生壁加厚期蔗糖代谢的影响

 【目的】研究日均最低气温对棉纤维中蔗糖代谢、纤维素沉积和纤维比强度形成的影响,揭示棉纤维强力变化的机理。【方法】通过分期播种,使棉铃发育处于不同的低温环境下,研究不同低温水平对新疆棉纤维发育过程中蔗糖代谢中相关物质含量变化、调控蔗糖代谢的关键酶活性变化的影响及与纤维素沉积的关系。【结果】正常播期条件下,棉株中部棉铃纤维中蔗糖合成酶（SS）和蔗糖磷酸合成酶（SPS）活性高,蔗糖转化彻底,纤维素累积时间长且累积平稳,最终纤维素含量高、纤维强力增加。播期推迟,棉铃发育过程中夜间温度降低,纤维中SPS活性下降、酸性转化酶（AI）和碱性转化酶（NI）活性升高,造成果糖含量明显上升,影响纤维素的沉积。【结论】棉纤维加厚期＜15.3℃的日均最低气温影响了蔗糖代谢关键酶活性的变化,引起蔗糖转化率下降,果糖循环速率减缓并在纤维中大量富集。     

乙烯利对宿根蔗生理生化特性和农艺性状的影响

桂糖17号和新台糖22号新植蔗分蘖初期，用100mg／L乙烯利喷施叶面，促进了宿根蔗出苗并提高了苗期的叶绿素含量。继续用100mg／L乙烯利分别在宿根蔗苗期、伸长盛期喷施叶面，结果显示：苗期喷施乙烯利促进了宿根蔗的生长，改善了宿根蔗的经济性状，增加了甘蔗产量；两个时期处理都提高了宿根蔗的有效茎数、成茎率和甘蔗品质，但伸长盛期喷施乙烯利，甘蔗的茎长、茎径、单茎重比对照低。在相对干旱时期，乙烯利处理的叶片相对含水量、束缚水／自由水比值都高于对照，而丙二醛含量、组织浸提液可溶性糖含量、电导率都低于对照，说明乙烯利处理提高了宿根蔗的抗旱性。     

草莓果实发育过程中糖代谢相关基因的表达分析

 为了分析草莓（Fragaria × ananassa Duch.）果实发育过程中可溶性糖积累与相关基因表达量的关系,以‘杜克拉’草莓7个发育时期的果实为试材,利用实时荧光定量RT-PCR的方法,分析果实发育中蔗糖转运蛋白及糖代谢关键酶（酸性转化酶、蔗糖合成酶和蔗糖磷酸合成酶）4个基因的表达量以及可溶性糖含量的变化趋势。结果表明,蔗糖、葡萄糖和果糖含量随着果实发育都呈逐渐增加的趋势,尤其蔗糖积累与果实成熟的关系较密切。随着果实发育,蔗糖磷酸合成酶基因表达量呈逐渐增加的趋势,尤其在果实发育的后期增加较快;蔗糖合成酶和酸性转化酶基因表达量除了白熟期和转色期外,呈逐渐降低的趋势;蔗糖转运蛋白基因表达量呈先升后降,降后又升的变化趋势,尤其在白熟期前急剧增加。结合可溶性糖和基因变化趋势分析表明,蔗糖转运蛋白和蔗糖磷酸合成酶在草莓果实发育过程中发挥着重要的作用。     

Leaf Carbon Isotope Discrimination and its Relation with Qualitative Root Traits and Harvest Index in Sugar Beet (Beta vulgaris L.)

Twenty commercial sugar beet varieties were grown at two sites in central Greece during the 2001 growing season (March to October), in a completely randomized block design with three replications. Carbon isotope discrimination (Δ) in sugar beet leaves was found to be affected by site and marginally by variety. No relation was found between fresh root yield and Δ, but significant correlations were found between Δ and sucrose content (positive) and between Δ and root α‐amino‐N (negative). Also, the harvest index, determined at one site, was negatively correlated with Δ.     

Improvement of the emulsifying properties of porcine sarcoplasmic proteins with a low-molecular weight surfactant by the two-step emulsification method

The emulsifying properties of porcine sarcoplasmic protein (SP) with or without low-molecular weight surfactants were examined. The emulsifying activity (EA) of SP was weaker than that of sodium caseinate (CA), blood plasma (BP) and whey protein isolates at a protein concentration of 0.5–3%. Sodium chloride decreased the EA of SP. The EA of SP was about one quarter that of CA in the presence of 3% sodium chloride. As homogenization time increased, the EAs of SP and BP decreased. The EA of SP was not influenced by sucrose stearate ester (SE) with a hydrophilic-lipophilic balance (HLB) value of 16 (SE-16) but was decreased by those with HLB values of 5 and 1. Low-molecular weight surfactants such as SE-16, Tween 80 and sodium cholate improved the EA of SP with the two-step emulsification method: corn oil was previously emulsified with the surfactant before addition of SP and homogenization. In the case of the addition of SE-16 as primary emulsifier, the EA was about twice as high as that of SP alone. The same effect was shown in the emulsions formed by CA and soy protein isolate. These results indicate that the emulsifying properties of meat protein would be improved by the addition of a low-molecular weight surfactant in a two-step emulsification.     

高等植物同化物的装载

本文简要综述了同化物向韧皮部装载的两种途径:质外体途径和共质体途径。一个比较合理的装载模式是载体和ATP酶参加的蔗糖—质子共运输模式。蔗糖浓度、生长调节物质、矿质元素和外界环境条件等对装载都有影响。     

板栗果实糖和淀粉积累及相关酶活性关系的研究

 以6年生板栗‘3113’为试材,采用比色法对果实发育过程中可溶性总糖、蔗糖和淀粉含量及相关酶活性的相互关系进行了研究。结果表明：果实横、纵径生长规律呈双“S”型,单苞质量呈“S”型曲线。可溶性总糖含量呈上升趋势,蔗糖含量呈下降趋势;淀粉含量呈单峰曲线。蔗糖合成酶（SS）和蔗糖磷酸合成酶（SPS）活性在花后60 d达到峰值,之后趋于下降,与蔗糖含量变化趋势吻合;ADPG焦磷酸化酶（AGPPase）、水溶性淀粉合成酶（SSS）、颗粒结合型淀粉合成酶（GBSS）的活性均呈单峰曲线,但最高峰的时间略有差异。相关分析表明,可溶性淀粉与可溶性总糖呈极显著的正相关,相关系数为0.978;SS和SPS活性与蔗糖存在极显著正相关,相关系数分别为0.905和0.892;可溶性淀粉含量与SSS活性呈显著正相关,与GBSS活性呈极显著正相关,相关系数分别为0.764和0.883。     

铁皮石斛可溶性糖含量与蔗糖代谢酶活性的相关性研究

通过对F型及H型铁皮石斛不同时期可溶性糖含量与蔗糖代谢酶活性的测定,并对其相关性进行分析,分析了可溶性糖的合成与蔗糖代谢酶活性间的关系。结果表明,移栽后F型和H型铁皮石斛叶片中蔗糖磷酸合成酶的活性与季节性变化趋势一致,但F型较H型高;蔗糖降解酶与可溶性糖含量及其还原糖间存在相关关系,达到显著水平。对可溶性糖和相关因子进行偏相关分析和通径分析可知,还原糖的直接通径系数最大为1.015,酸性转化酶的直接通径系数为负值(-0.356),与可溶性糖呈负相关关系,4个因子对可溶性糖含量的直接作用大小顺序为还原糖>酸性转化酶>中性转化酶>蔗糖。     

蔗糖密度梯度法定量口蹄疫完整病毒粒子（146S）的特异性研究

为验证蔗糖密度梯度法检测口蹄疫完整病毒粒子（146S）的特异性,选择pH值6．0、5．0、4．0PBS酸解处理3批提纯后的146S灭活抗原液,并将酸解后样品进行146S检测,发现8至11级份OD259峰值消失,146S含量由酸解前的1．77、6．60、3．67μg／mL至酸解后完全不能检测到。同时对3批不含病毒的细胞液按抗原纯化灭活工艺处理后进行146S检测,结果显示3批细胞液在8至11级份均没有明显吸收峰,而且其OD259值与PBS空白对照OD259值基本平行一致,说明不含病毒的细胞液对检测结果没有明显干扰。试验证明,蔗糖密度梯度法定量FMD病毒液中146S含量具有很好的特异性。