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1.
Solid wastes from white vinification, including grape peels, seeds and stems, were used as raw material for the recovery of antioxidant polyphenols. Extractions were performed using non-toxic media composed of water/ethanol mixtures and hydrochloric, acetic or tartaric acid. Recovery efficiency was assessed by monitoring the antioxidant potency of extracts and several indices related to their polyphenolic composition, including total polyphenol, total flavonoid, total flavanol and condensed tannin (proanthocyanidin) content. Among the by-products tested, seeds were shown to contain exceptional amounts of total polyphenols (13.76 g per 100g dry weight), followed by stems (7.47 g per 100g dry weight) and peels (0.97 g per 100g dry weight). Extracts with the highest antioxidant activity from all by-products were obtained with 57% ethanol. Acidification of this medium with 0.1% HCl improved polyphenol recovery and antiradical activity for stem extracts, but it was unfavourable for seed extraction.  相似文献   

2.
针毛收获蚁贮食行为及贮藏对种子活力的影响   总被引:2,自引:0,他引:2  
长有德  贺达汉 《昆虫知识》2002,39(6):445-450
针毛收获蚁Messoraciculatus(F .Smith)是我国西北荒漠草原生态系统中的种子收获性优势蚁类 ,收获、贮藏和取食多种 1年生荒漠植物种子 ,其中狗尾草、地锦、猪毛菜、雾冰藜最为典型 ,冬贮量分别为 1 92 ,1 1 2 ,0 5 1和 0 2 5g 1 0 0工蚁 ,分别占土壤种子库总量的 5 4 3 5 %~ 78 2 6% ,1 6 85 % ,1 1 7%和1 0 0 % ,占种子年产量的 79 5 6% ,1 6 73 % ,4 91 %和 3 1 49%。嗜于收获和贮藏的种子大小为 1 2~ 2 7mm ,重量为 0 8~ 2 0g 千粒。贮藏格局表现在不同穴巢深度所贮藏的种子种类和贮量不同 ;不同类型种子在贮藏小室中的堆放和混合方式不同 ;总贮量与社群总蚁量和蚁后数正相关。贮藏引起种子萌发能力显著降低。此外 ,对贮藏格局与种子形态特征的关系及该蚁在荒漠草原生态系统中的功能与地位进行了讨论。  相似文献   

3.
以大豆品种‘徐豆18'为对象,于2020年5月在邵阳学院试验基地设0(CK)、5、10、20和40 g·kg-1土壤添加生物质炭处理,分析盆栽大豆的生长发育、农艺性状和营养含量。结果表明: 与CK相比,施用生物质炭对大豆的生育期、株高、单株有效荚数、百粒重、叶片干重、茎秆干重和大豆籽粒中蛋白质、粗脂肪、异黄酮含量均具有显著影响。施用量为20 g·kg-1时,大豆的发芽率最高,生育期最短,单株有效荚数最多,百粒重最大,籽粒中蛋白质、粗脂肪和异黄酮含量最高。生物质炭施用量为40 g·kg-1时,大豆株高较高且贪青晚熟,单株有效荚数和百粒重比施用量为20 g·kg-1时降低。综上,土壤添加生物质炭对大豆农艺性状和营养含量的影响因施用量不同而异,其中20 g·kg-1为本试验条件下的最佳施用量。  相似文献   

4.
This study analyzed boron content in commonly consumed foods by Koreans. Boron content was analyzed on 299 different foods using inductively coupled plasma atomic emission spectroscopy. The content of boron in cereals, potatoes, starches, sugars, and confectionaries was 1.11 to 828.56 microg per 100 g. As for beans, nuts, and seeds, the content of boron in acorn starch jelly was 66.15 microg per 100 g and in soybeans 1,642.50 microg per 100 g. In fruits, records show 5.29 to 390.13 microg per 100 g. The content of boron in vegetables was 17.45 to 420.55 microg per 100 g and in mushrooms 2.97 to 526.38 microg per 100 g. As for meats, eggs, milks, and oils, it posted 1.48 to 110.01 microg per 100 g. Fishes, shellfishes, and seaweeds contained 1.20 to 6,300.83 microg per 100 g of boron. Beverages, liquors, seasonings, and processed foods posted 1.06 microg per 100 g in corn cream soup and 2,026.49 microg per 100 g in cocoa. It is suggested that the data for the analysis of boron content in foods need to be more diversified and a reliable food database needs to be compiled based on the findings of the study to accurately determine boron consumption.  相似文献   

5.
It was shown that rRNA and HnRNA synthesis in rat liver nuclei does not change-within 30 min after intraperitoneal injection of acetylcholine (0.005 mg per 100 g of body weight) but decreases after injection of norepinephrine and epinephrine (0.05 mg per 100 g of body weight). The synthesis of rRNA (but not of HnRNA) increases after injection of hydrocortisone (2,5 mg per 100 g of body weight). The synthesis of HnRNA (but not of rRNA) increases after injection of ACTH1-24 (3 ME per 100 g of body weight) and oxytocin (1 ME per 100 g of body weight). The synthesis of rRNA decreases after injection of propranolol and atropine (0.5 mg per 100 g of body weight). At the same time, the synthesis of HnRNA does not change thereby. The inhibitory effect of propranolol and atropine was corrected by electrostimulation of hypothalamus. The content of cAMP and Ca2+ and the phosphorylation degree of nuclear proteins are increased after stimulation of hypothalamus. The phosphorylation of nuclear proteins is increased by 10(-8)-10(-6) M cAMP. The synthesis of RNA in liver nuclei is increased by 10(-6) M cAMP only after addition of cytosol. In this case the activity of RNA-polymerase II increases in a greater degree than that of RNA-polymerase I + III. It is assumed that the regulatory mechanisms of rRNA and HnRNA synthesis are different. The role of hypothalamus electrostimulation, neurotransmitters, hormones, and cAMP in the mechanisms of RNA synthesis in rat liver nuclei is discussed.  相似文献   

6.
A detailed examination of the ordinary 1980 fruit crop of an ordinary large adult guanacaste tree (Enterolobium cyclocarpum) in Guanacaste Province, Costa Rica (1980) shows that for fruits with about 6-16 seeds (range, 1-18 seeds per fruit) there is about ***1 g dry weight fruit tissue per seed (seeds averaging about 820 m each). Fruits that have about 1-5 seeds on average have 1.5-3 times as much dry fruit tissue per seed as do the seed-rich fruits, and also contain seeds that weigh about 8% more on average than the seeds in the seed-rich fruits. The average seed weight per fruit was found to decrease slightly if all sizes of fruits are considered, but to remain essentially constant over the range of 7-16-seeded fruits. This category contained 78% of the fruits. These findings suggest that different parts of the seed crop may end up in different dispersers and dispersers with different preferences for fruit seediness and tolerances for seed size may remove different portions of the seed crop.  相似文献   

7.
玉米自交系间杂交种F1农艺性状的主成分分析   总被引:1,自引:0,他引:1  
用Hótlling倡导的主成分分析法,(Principal comporient analysis),分析了玉米32个自交系间80个杂交组合的F_1世代.分析性状有株高、穗位高、雄穗分枝数、单株有效穗数、穗长、秃尖长、穗行数、行粒数、穗重、百粒重和单株产量.结果表明,前4个主成分贡献率占了总变异的大部分,因此就前4个主成分得分值对80个杂交组合进行了选择,为玉米组合的选择提供了直接依据.  相似文献   

8.
探讨不同发育时期水曲柳种子的外部形态和生理变化及其层积处理后的萌发效应结果表明:水曲柳开花120d后为成熟脱水阶段,开花110d后种子的胚长和胚乳干重趋于稳定,花后110~120d期间种子胚干重趋于稳定;花后70~100d采集的种子不耐层积,层积处理后逐渐死亡,花后110d采集的种子经层积处理后可以萌发;110d后采集的水曲柳种子经暖温(20℃)16周+低温(5℃)12周的层积处理后,其休眠破除的效果较好,适当延长暖温层积时间有利于提高种子萌发率。  相似文献   

9.
Content of low-molecular-weight thiols during the imbibition of Pea seeds   总被引:5,自引:0,他引:5  
The metabolism of low-molecular-weight thiols was investigated in seeds of Pisum sativum L. cv. Kleine Rheinländerin during imbibition in water for 14 h. The amount of oxidized glutathione (GSSG) decreased from 319 nmol (g dry weight)−1 in dry seeds to 38 nmol (g dry weight)−1 within the first 14 h of imbibition. The decrease may have been due to the reduction of GSSG to reduced glutathione (GSH), catalyzed by the enzyme glutathione reductase (GR; EC 1.6.4.2). The enzyme activity was high in dry seeds [25 nkat (g dry weight)−1] and decreased to 20 nkat (g dry weight)−1 within 14 h of imbibition. The activity of glucose-6-phosphate dehydrogenase (EC 1.1.1.49) decreased from 100 nkat (g dry weight)−1 in dry seeds to 67 nkat (g dry weight)−1 after 14 h of imbibition. Within 14 h the amount of γ-glutamyl-cysteine (γ-GC) decreased from 135 to 38 nmol (g dry weight)−1, whereas the cysteine content rose from 81 nmol (g dry weight)−1 in dry seeds to a maximum of 170 nmol (g dry weight)−1 after 12 h of imbibition, which may be due to the degradation of γ-GC into cysteine.  相似文献   

10.
天然次生林中水曲柳种子的扩散格局   总被引:16,自引:1,他引:15       下载免费PDF全文
 种子扩散是种群动态中的一个关键环节,研究其扩散格局对了解种子库及更新格局有重要意义。于1999~2000年在天然次生林中选择样地并设置样带,共设取样点1376个,观察和估计了水曲柳(Fraxinus mandshurica)的种子雨格局。结果发现,母树附近,尤其是冠幅范围内,各方向的种子雨没有显著差别。但种子雨密度随距离有明显变化,冠幅范围内平均可达462~903个·m-2。距冠缘10~20 m急剧减少,为50~190个·m-2。72.5%~96.4%的种子散落在距母株树干10 m 的范围内。饱满种子顺风  相似文献   

11.
This paper presents the content and composition of free sterols in a number of Astragalus species from Iran. Free sterols of roots and seeds were analysed quantitatively and qualitatively by gas-liquid chromatography. Four major 3-beta-hydroxysterols (cholesterol, campesterol, stigmasterol and beta-sitosterol) were identified in roots of 18 species and in seeds of five species of Astragalus. beta-Sitosterol was the main free sterol in both roots and seeds. The cholesterol content in seeds was higher than that in roots. Trace amounts of cholesterol were detected in roots of only four species. beta-Sitosterol accounted for 34.4-69.2 and 76.8-81.8% of the total lipid content in roots and seeds, respectively. The beta-sitosterol content in roots and seeds of Astragalus species varied from 6.3 to 35.7 and 93.3 to 164.5mg/100g dry weight, respectively. Total free sterol content in seeds varied from 112.09 to 204.04mg/100g dry weight, significantly higher than those in roots (7.5 to 43.4mg/100g dry weight). The chemotaxonomic values of free sterols and total lipid profiles of some of the representative species are discussed.  相似文献   

12.
Variation in seed weight is common within and among plant species, but few studies have attempted to document the pattern of seed weight and germination attributes for aquatic macrophytes at a large scale. This study examined within‐species variation in seed weight and germination attributes and the effects of environmental factors on seed traits of the submerged plant Potamogeton pectinatus in the arid zone of northwest China. Our results showed that the average seed weight was 0.24 g per 100 seeds with a coefficient of variation (CV) of 28.4% among the eight P. pectinatus populations. The total germination fraction of seeds of P. pectinatus was relatively poor, less than 35% in seven P. pectinatus populations, and the lowest germination percentage found was only 2%. There were significant differences in seed weight, time to onset of germination, and total germination fraction among the eight different populations. Hierarchical partitioning analysis showed a strongly positive correlation between seed weight and water temperature and pH. Seed weight and the maternal environmental factors significantly affected both time to initiation of germination and total germination fraction. Our results suggest that (1) seed weight variation in P. pectinatus primarily is the result of temperature variation during fruit development; (2) relatively poor germination fraction suggests that seeds are relatively unimportant in the short‐term survival of populations and that it may be another adaptive trait allowing plants to take place in the right place and at the right time, especially in harsh environment; and (3) variation in seed germination traits should be determined by local environmental and intrinsic factors that interact in a complex fashion.  相似文献   

13.
Abstract: We investigated habitat characteristics, seed type and seed size variation between and within 41 populations of the heteromorphic saltmarsh annual Spergularia salina. 95% of the investigated populations were truly heteromorphic regarding unwinged or winged seeds but either of the seed types could dominate in individual populations. 39% of all seed capsules contained mixed seed types, in 43% of capsules the seeds were exclusively unwinged, and in 18% only winged seeds were found. In a closer survey in one of the populations (at Tullgarn, 5850'N, 1737'E), albeit predominantly heteromorphic, again capsules either contained mostly unwinged or winged seeds: 59% of the capsules had mixed contents, 21% contained exclusively unwinged seeds, and 21 % produced only winged seeds. Seed weight varied up to 10-fold, with an overall mean of 77.2μg. 27% of this variation was due to variation among populations, 52% was explained by variation between individuals, and 21% was due to variation within individuals. Seed weight was positively correlated with the frequency of winged seeds per capsule, especially within populations, and negatively correlated to seed number. The frequency of winged seeds in each capsule and seed weight was positively correlated with population density both between and within populations.  相似文献   

14.
Laboratory studies were conducted to assess tomato, Lycopersicon esculentum Mill. (Solanaceae), quality in relation to the level of buzz-pollination by bumble bees. Studies were conducted in commercial tomato greenhouses in the Leamington, Ontario, area to categorize bruising of tomato anther cones by bumble bees into five levels of bruising. The number of pollen grains per stigma was determined for each bruising level, and the bruising level was found to be a good predictor of stigmatic pollen load. Experimental flowers were pollinated by bumble bees and assigned to bruising levels based on the degree of anther cone discoloration. Fruit set, tomato weight, minimum diameter, the number of days until ripe, roundness, weight, percentage sugars, and number of seeds were assessed and compared among bruising level. Fruit set in flowers receiving no pollination visits was 30.2%, whereas, 83.3, 84.4, 81.2, and 100% of the flowers set fruit in bruising levels 1, 2, 3, and 4, respectively. Minimum diameter, number of seeds, and tomato weight all increased from no bruising to different levels of bruising. There was no increase in weight or diameter above a bruising level of 1, and no increase in the number of seeds per fruit after a bruising level of 2. We found that pollination of tomato flowers greater than a bruising level of 2 (corresponding to approximately one to two bee visits) did not result in a significant increase in quality.  相似文献   

15.
太白红杉 (Larixchinensis) 是仅分布于我国陕西秦岭境内的国家二级保护植物, 研究其生殖规律将有助于加深对其濒危原因的认识。该文用单因素方差分析的方法研究了太白红杉种实数量特征, 并用Pearson相关系数检验了不同环境条件下的变化及其与环境因子和植株生长状况的关系, 结果表明种实数量特征在不同环境条件下差异明显, 太白山国家森林公园单株种子产量最高 ;长安光头山平均每株产生的种子总重、球果总重和球果平均重量最重, 平均每株球果数目和每球果种子数也是最多。多重比较表明牛背梁种群太白红杉种子千粒重最重。其中球果的种子数在小种群中较多 ;每株的种子总重量、球果平均重和球果总重在小种群中较重。太白红杉种实数量特征与海拔、坡度和坡向呈负相关, 与植株年龄呈正相关, 球果的种子数目与年均温呈正相关 (p <0.0 5 ), 而与一月均温呈负相关 (p <0.0 5 ) 。种子大小与种子总数呈弱正相关, 种子大小和数目间不存在权衡 (Trade-ff) 。  相似文献   

16.
草木灰对四种松属种子发芽和幼苗生长的影响   总被引:2,自引:0,他引:2  
刘发林 《生态学报》2017,37(17):5673-5680
火干扰不仅影响森林生态系统的结构与功能,而且影响群落更新与演替。为了研究草木灰对4种松属种子萌芽和幼苗生长的影响,在湖南省株洲市黄丰桥林场采集马尾松、云南松、湿地松和火炬松种子,以马尾松次生林火烧迹地的草木灰为基质,设置对照和3个草木灰处理,进行播种试验及生长观测。结果表明:(1)草木灰处理下4个物种的种子发芽率比对照试验低,并呈现随草木灰含量的增加而降低的趋势,低草木灰含量处理马尾松种子发芽率不及对照一半,中、高草木灰含量处理发芽率更低;云南松、湿地松和火炬松种子发芽率规律类似于马尾松,而高草木灰含量处理发芽率为0。(2)培养皿播种平均发芽时间比花盆播种长,无论草木灰处理还是培养条件(培养皿或花盆),马尾松和云南松种子平均发芽时间比湿地松和火炬松短。(3)4个物种种子播种14周后,对照试验中马尾松和云南松幼苗死亡率最低,而火炬松和湿地松幼苗死亡率相对增加。(4)播种14周后不同试验处理4个物种幼苗生长差异不明显。火炬松、湿地松、云南松和马尾松幼苗的单株平均干重分别达0.038、0.031、0.027、0.024 g。各物种叶干重按降序排列依次是火炬松(0.026 g)湿地松(0.019 g)云南松(0.017 g)马尾松(0.016 g),根和茎的干重比重相当,约占对应物种幼苗叶干重的三分之一。研究表明以草木灰为培养基质,马尾松和云南松种子的发芽率较高,平均发芽时间较短,更适合作为火烧迹地植被恢复先锋树种,为火干扰后选择人工促进天然更新树种提供参考。  相似文献   

17.
An experiment was conducted to determine the efficacy of a so-called consensus phytase preparation produced by Hansenula polymorpha on growth, tibia and toe ash and P retention of young turkeys. A total of 192 female turkeys (BUT 9 strain) were placed into 96 batteries at two per cage and assigned to one of eight diets: A negative control containing 2.5 g non-phytate P per kg feed (T-1); T-1 plus 125, 250, 500, 1000 or 10 000 phytase units (U) per kg feed, respectively, (T-2 to T-6); T-1 plus 0.5 or 1.0 g Pi/kg feed as dicalcium phosphate dihydrate (DCP), respectively, (T-7 and 8). The experiment lasted 32 d, and excreta were collected and weighed between 26 and 29 d of age. Feed was also weighed during this period in order to calculate P retention. Performance was calculated for the 0 to 32 d period. At the end of the experiment one bird per pen was killed for tibia and toe ash content determination, except for T-2, T-3, and T-7. Body weight, FCR, toe and tibia ash, and P retention responded to phytase or Pi supplementation. Using linear or quadratic models for comparing performance of the treatments containing supplemental Pi with phytase treatments, an equivalence between phytase and Pi was calculated. Body weight, toe ash, tibia ash and P retention showed a significant response to phytase supplementation. The values of equivalence for body weight, toe ash, tibia ash and P retention were 251, 597, 391 and 390 U to 1 g Pi/kg feed. At 10 000 U/kg feed there was a significant response in terms of weight gain and P retention, indicating that turkeys respond to levels greater than 1 000 U/kg feed.  相似文献   

18.
为了探究中华鳖(Pelodiscus sinensis)幼体的补偿生长能力,我们对中华鳖幼鳖(平均湿重9.56g)进行如下6种处理:饥饿0(对照)、1、2、3、4周,或者食物限制4周,即只投喂体湿重百分之一的食物;然后对各组进行饱食处理直到10周的实验结束为止。结果发现在饱食期的第一周各饥饿处理组的特殊生长率均显著高于对照组(P〈0.05),但是终体重均没有赶上对照组。当饥饿或食物限制结束时,脂肪含量随着饥饿期的延长而降低,灰分和水分则表现出相反的变化趋势:脂肪含量显著低于对照(P〈0.05),而灰分和水分则显著高于对照(P〈0.05)。蛋白含量则没有显著变化(P〉0.05)。实验结束时,除了灰分外(P〈0.05),其他个体组成指标均恢复到对照组的水平。以上结果表明中华鳖幼体在饥饿胁迫下首先利用脂肪作为主要能源以维持生存,以及在该研究条件下完全的食物剥夺可以诱发其部分补偿生长反应.而部分食物剥夺则不能诱发此反应。  相似文献   

19.
盐城滩涂沙棘叶营养成分年动态研究   总被引:3,自引:0,他引:3  
以2003年4月~10月在盐城滩涂区沙棘(H ipp ophae rham noid es subsp.sinensis)林地采集的沙棘叶为材料,采用高效液相色谱法(HPLC)测定氨基酸、维生素和黄酮类物质的含量,并分别用ICP-M S和ICP-AES方法测定有毒重金属Cd、Pb和其它微量元素的含量.结果表明:(1)C a、K、M g、Zn和F e的含量分别在4.860~12.194g/kg、6.361~11.001 g/kg、2.302~3.833 g/kg、25.5~31.0 m g/kg和211~598 m g/kg干重之间;Pb和Cd的含量分别在0.83~2.13 m g/kg和0.29~0.94 m g/kg干重之间;(2)18种氨基酸总含量在13.33~18.41 g/100g干重之间,其中天冬氨酸、色氨酸和谷氨酸含量较高.(3)维生素C、维生素E、芦丁、槲皮素、异鼠李(黄)素含量分别在124.3~190.5 m g/100 g、4.16~7.97 m g/100 g、141.23~352.67 m g/100 g、6.71~32.62 m g/100 g和1.72~3.79 m g/100 g干重之间;(4)粗蛋白、粗脂肪、粗纤维和粗灰分含量分别在15.16~22.42 g/100 g、4.36~11.94g/100 g、12.34~17.38 g/100 g和4.90~9.81 g/100 g干重之间.沙棘叶含有丰富的微量元素、氨基酸、维生素和黄酮类物质等营养成分,具有较高的营养价值,可作为动物饲养和其它工业利用的原料.  相似文献   

20.
半干旱黄土丘陵区沙棘优良品种引种选育试验研究   总被引:7,自引:2,他引:5  
1985-1998年先后在黄土高原半干旱区的陕西吴旗,安塞县进行了沙棘优良品种引种选育试验研究。通过引种国内不同地理种源20余种优良沙棘类型。引进俄罗斯优良沙棘品种,采用家系选择法进行试验研究,初步筛选出生态经济型5种沙棘类型,经济型2种类型。前者生长迅速,树冠好,根系发达,郁闭快,水土保持效益好,且果实较大(果径0.8-0.9cm,百果重20-31g),单株产果量为2-3.5kg,Vc和含油量较高,其生态,经济性状较当地野生沙棘为好。此种类型沙棘适于在黄土丘陵大面积荒沟,荒坡种植,通过引种俄罗斯大果,无刺沙棘为好。此种类型沙棘适于在黄土丘陵大面积荒沟,荒坡种植,通过引种俄罗斯大果,无刺沙棘优良品种与本地野生中国沙棘对比分析看,出,其适应性,抗性较中国沙棘差,经济性状较好,通过试验筛选出2种优良类型,果径为0.9-1.3cm,百果重46-52g,单株产果量2-3.5kg,无刺或少刺,此项研究为在半干旱黄土丘陵区大面积荒山,荒沟建造高产,优质沙棘林,高效,持续发展沙棘产业具重要意义,在引种试验中必须掌握好其关键技术,建立好采穗圃,种子园,并建立一定面积的集约经营的高产,优质沙棘园及良种繁育基地,掌握好抚育管理技术,特别是水,肥管理技术。  相似文献   

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