不同含水量大葱种子贮藏过程中的糖代谢研究

将大葱种子干燥到1．8％～10．5％的不同含水量后,在50℃、35℃、20℃和-18℃条件下密闭贮存16个月。通过对半乳糖、葡萄糖、果糖、蔗糖和密三糖含量研究的结果表明,随着贮存温度的升高,种子中半乳糖的含量不断升高,随着含水量的降低,种子中半乳糖的含量逐渐降低,且随着贮存温度的下降,种子中半乳糖含量随种子含水量下降而降低的趋势减缓。然而葡萄糖、果糖、蔗糖和密三糖的结果与半乳糖的变化趋势相反,随着贮存温度的升高,4种糖的含量逐渐下降,在同一贮藏温度条件下,随含水量的降低这4种糖的含量却逐渐升高,但在贮存温度较低时（20℃和～18℃）,这种变化趋势不明显。     

含水量对种子贮藏寿命的影响

建立以收集种子为主体的基因库乃是当今保护植物种质资源最为普遍且可靠易行的方式,在世界库存约 61 0 0 0 0 0份种质资源中,近 90 %是以种子形式保存于约 1 30 0个基因库中。低温贮藏仍是目前基因库中种子种质保存的主要方法。种子含水量和贮藏温度是影响种子在贮藏期间生活力和活力保持的关键因素。传统的经验认为控制温度比控制水分来得安全有效,因而趋向于向低温或超低温的贮藏方向发展。国际植物遗传资源研究所（ＩＰＧＲＩ）曾推荐 5%～ 6%的含水量和 - 1 8～- 2 0℃低温作为各国长期保存种子的理想条件。目前,世界各国都把更多的…     

AFLP技术运用于小麦种子超干燥保存遗传完整性的初探

小麦种子被干燥和超干燥至9．0％,8．0％,7．0％,6．0％,5．0％,4．0％后,密封包装于江西南昌常温保存。保存五年后,发芽结果表明,小麦种子于亚热带地区常温保存,必须先经过干燥密封包装。种子最适含水量介于7．0％～9．0％之间。不同品种阃有差异。种子经发芽生长至三叶一心期,取幼苗(茎与叶),用AFLP分子技术对其单株及20株的混合样品进行遗传稳定性鉴定。结果表明,每对引物的AFLP图谱谱带丰富,不同引物的清晰带有26至52条,不同品种间差异带在3至6条。同一品种不同的含水量之间AFLP图谱谱带整齐划一,未见明显差异。同一含水量不同混合样品或单株样品间也未见差异,表明小麦种子经干燥、超干燥后于亚热带地区(江西南昌)常温保存五年后。在AFLP分子水平上未见遗传变异。同时本研究也为贮藏种子的遗传完整性研究提供了一个新的思路。     

超干贮藏杜仲种子的研究

杜仲种子含水量降至３．５％以下,其耐藏力增强。经５０℃１０天人工加速老化后,表现出较强的抗老化能力。室温贮藏２年后,与５℃、－２０℃条件贮藏种子相比,发芽率、根长及活力指数等均无显著性差异。超干种子比对照种子（含水量７．５％,室温贮藏）电导率降低４５％;脂质过氧化产物丙二醛（ＭＤＡ）的积累减少;对脱氢酶活性的保持能力比常规种子增强。超干种子幼苗的吸氧量高于对照种子。经过氧化物酶同工酶谱分析,超干种     

贮藏温度和种子含水量对洋葱种子发芽率的影响

贮藏温度低于15℃时,温度对洋葱种子发芽率影响变小,种子含水量低于8.8%时,其衰老过程变慢,高含水量种子在高温下贮存,衰老过程加快,含水量为100%和13%的种子在25℃下贮存分别不到5个月和2个月就失去商品性。     

洋葱种子含水量与贮藏温度对其寿命的影响

不同含水量（MC 7．1％－1．2）的洋葱种子贮藏在35℃、室温、15℃和5℃条件下1－3年,适度超于处理能延长种子的贮藏寿命;种子的贮藏寿命与种子含水量和贮藏温度密切相关。种子贮藏的最适含水量随温度的改变而发生相应的变化,35℃时MC为3．4％;室温时为3．4％－3．5％;15℃时为4．5％－5．1％。MC≤2．2％不利于延长种子寿命。在室温自然条件下贮藏1－3年,适度超干种子（MC3．4％）内MDA和H2O2含量、O2^-产生速率和LOX活性明显地低于未超干种子（MC7．1％）和高度超干种子（MC1．2％）,而抗氧化酶AsA-POD 、CAT和SOD的活性显著地高于未超干种子（MC7．1％）和高度超干种子（MC1．2％）。据此认为对脂质过氧化的抑制作用是适度超干种子耐贮藏的生理原因之一。     

辣椒种子的超干研究

辣椒种子含水量(MC)降至5％以下,能显著提高抗老化劣变的能力。在同等老化处理(50C15d)后,对照种子(MC=7．5％)发芽势已大幅度下降,而超干种子(MC=4．1％～1．4％)的发芽势与未老化种子相同。超干种子脱氢酶活性明显高于同等老化条件下的对照种子,而丙二醛的含量则显著低于对照种子。电导率测定结果表明,超干种子细胞膜系统的完整性良好。     

超干贮藏提高梭梭种子的耐贮藏性

梭梭(Haloxylon ammodendron Bge.)的种子为短命种子,在自然状态下,种子的含水量为8.5%,寿命约为10个月.将梭梭种子含水量降至2.5%和1.4%,其耐贮藏力增强.经过50 ℃下5 d和10 d的人工加速老化后,超干种子表现出较强的抗老化能力.与对照相比,超干种子具有较高的萌发率、活力指数及较长的根,其细胞膜具有较低的电导率和较高的脱氢酶活性.     

超干贮藏提高梭梭种子的耐贮藏性

梭梭 (HaloxylonammodendronBge .)的种子为短命种子 ,在自然状态下 ,种子的含水量为 8.5 % ,寿命约为 10个月。将梭梭种子含水量降至 2 .5 %和 1.4% ,其耐贮藏力增强。经过 5 0℃下 5d和 10d的人工加速老化后 ,超干种子表现出较强的抗老化能力。与对照相比 ,超干种子具有较高的萌发率、活力指数及较长的根 ,其细胞膜具有较低的电导率和较高的脱氢酶活性     

洋葱种子含水量与贮藏温度对其寿命的影响

不同含水量（MC7.1％～1.2％）的洋葱种子贮藏在35℃、室温、15℃和5℃条件下1～3年,适度超干处理能延长种子的贮藏寿命;种子的贮藏寿命与种子含水量和贮藏温度密切相关。种子贮藏的最适含水量随温度的改变而发生相应的变化,35℃时MC为3.4％;室温时为3.4％～4.5％;15℃时为4.5%～5.1％。MC≤2.2％不利于延长种子寿命。在室温自然条件下贮藏1～3年,适度超干种子（MC3.4％）内MDA和H2O2含量、O－*2产生速率和LOX活性明显地低于未超干种子（MC7.1％）和高度超干种子（MC1.2％）,而抗氧化酶AsA-POD、CAT和SOD的活性显著地高于未超干种子（MC7.1％）和高度超干种子（MC1.2％）。据此认为对脂质过氧化的抑制作用是适度超干种子耐贮藏的生理原因之一。     

Studies on the Peanut Seed Vigor Stored in Different Gases

Peanut seeds (water content 6.21% ) were stored at 38–40 ℃ for artificial ageing storage with different gases. N2 or CO2 delayed peanut seed ageing in comparison with air. The rate of seed germination was not affected by storing for 26 weeks under N2 or CO2, but the vitality of seed lost when stored under air. Determination of peanut seed vigor (root length+ axial length)×percentage of germination may precisely show the change in seed quality during ageing. The results indicate the positive correlation between the respiration and subsequent growth in peanut seeds, and the significantly negative correlation between vigor and electrical conductivity or sugar content in the seed extract.     

不同群落中四川大头茶 (Gordonia acuminata)花粉游离脯氨酸含量与种子产量

 四川大头茶(Gordonia acuminata)是缙云山亚热带常绿阔叶林的优势树种之一。对缙云山3种不同群落中四川大头茶的花粉游离脯氨酸含量和果实的种子产量进行了研究,发现花粉游离脯氨酸含量和每果种子产量在同一群落中的不同龄级四川大头茶个体间没有差异,但在不同群落间表现出差异。常绿阔叶林中的四川大头茶个体具有最高的花粉游离脯氨酸含量和每果种子产量,四川大头茶纯林中的次之,针阔混交林中的最低。分析发现,四川大头茶花粉游离脯氨酸含量与果实的种子产量有密切的正相关关系,花粉中的游离脯氨酸含量可以作为一种预测和比较相同地区不同生态环境中四川大头茶种子产量的指标。     

Effects of Cricket Extract on Lipid Metabolism and Body Fat Content in High- Fat Diet Fed Rats

The effect of cricket extract on high‐fat diet fed rat was observed. It was shown that cricket extract prevented the increment of body weight by high‐fat diet. The extract also decreased the value of AST in liver. The most significant effect of the extract was shown on lipid metabolism. The contents of total lipid and total cholesterol in liver and feces were reduced by the extract on dose‐dependent. These statistically significant results were clear in 3% extract treated group (HFD3) while were slight in 1% extract treated group (HFD1). The same result was also shown in body fat content.     

Skeletal Muscle Metabolism and Body Fat Content in Men and Women

The purpose of the present study was to verify the relationships between indicators of body Eat content and specific characteristics of skeletal muscle in a large sample of men and women. Six skinfold thicknesses (σ6S) and maximal oxygen uptake (VO₂ max) were measured in 348 Caucasian subjects (149 women and 199 men). Fiber type proportions (type I, type IIA, and type IIB) and activity levels of marker enzymes for the Krebs cycle (malate dehydrogenase, MDH) and for the fatty acid oxidation (3-hydroxya-cyl CoA dehydrogenase, HADH) pathways were determined in vastus lateralis muscle samples. No significant correlation was found between fiber type proportions and σ6S. Significant and negative correlations were, however, obtained in both genders between the σ6S and MDH enzyme activity (r = ?0.23; p<0.01), but not between the σ6S and HADH enzyme activity. When individuals with low and high amount of subcutaneous fat but paired for VO₂max were compared, vastus lateralis of fat men exhibited the same proportion of type I fiber (38.6 ± 10.3 vs 38.5 ± 13.4 %) and HADH activity level (3.43 ± 1.05 vs. 334 ± 0.81 U/g), but had about 20% less MDH enzyme activity than vastus lateralis of leaner men (158 ± 35 vs. 198 ± 43 U/g;p<0.05). No difference was found in any of these muscle phenotypes when comparisons were made between women with low and high amount of subcutaneous fat but also paired for VO₂max. Moreover, no relations were observed between skeletal muscle fiber type proportion or metabolic markers with relative subcutaneous fat distribution. In conclusion, these results indicate that the proportion of fiber type of skeletal muscle is not a determinant of body fat content or fat distribution in men and women. However, the results of the present study suggest, at least in men, that a low oxidative capacity of skeletal muscle, undetected by muscle fiber typing, is associated with an augmented body fat content.     

中国黍稷种质资源蛋白质和脂肪含量的鉴定分析

对来源于我国14省（区）的6515份黍稷种质资源,通过3次大批量的蛋白质和脂肪含量的鉴定分析,计算出黍稷蛋白质、脂肪的平均含量。筛选出一批蛋白质含量15．00％以上的高蛋白种质和脂肪含量4．00％以上的高脂肪种质,以及蛋白质含量15.00％以上、脂肪含量4．00％以上的双高种质,提供我国黍稷生产和育种利用。     

云南不同种皮色地方稻种的总黄酮含量及其对种子萌发的影响

为了解不同种皮色地方稻种的总黄酮含量与其种子萌发品质的相关性,测定了17份云南地方稻种谷粒、糙米和谷壳的总黄酮含量,以及谷粒和糙米的发芽势、发芽率、发芽指数和活力指数4项萌发指标。结果表明,红皮和紫皮谷粒及糙米的总黄酮含量显著、极显著高于白皮,而谷壳的总黄酮含量则无明显差异。红皮谷粒的4项萌发指标均高于紫皮和白皮,但仅红皮与白皮谷粒之间的发芽势差异达到极显著水平;红皮糙米的4项萌发指标极显著地高于紫米和白米,且除发芽指数外,紫米的其他3项萌发指标显著或极显著地高于白米,表明有色种皮谷粒、糙米的总黄酮含量较高,其萌发指标也相应较高。相关分析表明,谷粒的总黄酮含量与4项萌发指标之间没有明显的相关性,但糙米的总黄酮含量则与4项萌发指标呈显著正相关;谷壳的黄酮含量与种子萌发无关,而糙米的黄酮含量则显著地影响种子的萌发特性。     

Urban Metabolism and the Energy Stored in Cities

Using the city of Toronto as a case study, this article examines impacts of energy stocks and flexible demand in the urban metabolism on the resilience of the city, including discussion of directions for further study of the resiliency of the urban metabolism. An important element developed is the nominal residence time of the energy stocks. This value defines how long an energy stock lasts under typical patterns of energy use. The findings suggest that the residence times of many sources of energy overcome vulnerability when energy supply shocks last on the order of hours or a few days, but that the measure is limited to assessing only certain types of commonly used energy sources in aggregate terms. Discussion is included on the uncertainty of this measure and on the metabolic and resiliency implications of new technologies intended to reduce energy use and improve sustainability of cities and the use of the urban metabolism as a means of comparison. The methodology employed highlights how waste energy could be used to increase the resiliency of the city's water supply, but also how the study of the urban metabolism would benefit from a more disaggregate form in the study of sustainable and resilient cities.     

不同生长期蛋鸡的体脂水平和肝脏脂肪酸合成酶活性的关系

 不同生长期蛋鸡的体脂水平和肝脏脂肪酸合成酶活性的关系田维熙,董妍,权晖,陈文峰（中国科学院研究生院生物教学部,北京１０００３９）动物体脂的控制是一个复杂过程．不同种类不同年龄的动物体脂水平有很大差异,控制机制是什么,哪些是关键的控制因素？不久前我们曾...