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11.
利用染色分析法确定农田土壤中硝态氮垂直运移的研究 总被引:1,自引:3,他引:1
利用农田土壤剖面染色并结合田间硝态氮示踪的方法,研究了太湖地区典型的水稻土—白土剖面中优势流和硝态氮在土壤剖面中的运移规律。结果表明:染色法可以分析土壤剖面中大孔隙的分布状况和优势流的路径;染色面积越大的土层,表明该土层的大孔隙含量就越高。在白土剖面上,表层的大孔隙含量最高,20~30 cm和55~100 cm土层以下大孔隙含量都很低。在田间条件下,优势流是影响硝态氮迁移的主要因素;白土剖面中优势流直接影响的最大深度为78 cm,对地下水的影响很大。本试验中地下水的硝态氮含量比未试验前增加了10多倍,这对环境安全影响极大。 相似文献
12.
Analysis of petal anthocyanins to investigate coloration mechanism in herbaceous peony cultivars 总被引:1,自引:0,他引:1
Petal coloration and anthocyanin compositions of 41 herbaceous peony cultivars were analyzed. Anthocyanins were identified by high-performance liquid chromatography–electrospray ionization-mass spectrometry (HPLC–ESI-MSn) coupled with photodiode array detection (DAD). Peonidin-3,5-di-O-glucoside (Pn3G5G), pelargonidin-3,5-di-O-glucoside (Pg3G5G), cyanidin-3,5-di-O-glucoside (Cy3G5G), peonidin-3-O-glucoside (Pn3G), and cyanidin-3-O-glucoside (Cy3G) were the five major anthocyanins in herbaceous peony cultivars. Deep purple or reddish purple cultivars contained 4–5 anthocyanins, whereas pink cultivars only contained Cy3G5G and Pn3G5G, and their contents were much lower than those of purple cultivars. According to the chemical structures of three anthocyanidins in association with petal coloration, flowers were classified into three phenotypes: 1. “Pn, Cy, and Pg” (all purple flowers including two pink flowers); 2. “Pn, Cy” (pink flowers); 3 “Pn” (light pink and white flowers). The coloration mechanisms of cultivars with the pink and purple flowers were quite different. Correlations between lightness (L*) and chroma (C*), chromatic component a* and total anthocyanins (TA) value, a* and co-pigmentation index (CI) showed opposite tendencies, whereas L* and TA showed the same tendency in each group. High contents of Pn3G5G and Pg3G5G may responsible for the purple coloration of herbaceous peony cultivars. 相似文献
13.
Effects of dietary supplementation of Haematococcus pluvialis powder on gonadal development,coloration and antioxidant capacity of adult male Chinese mitten crab (Eriocheir sinensis)
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Xugan Wu Lei Zhao Xiaowen Long Jianguo Liu Fang Su Yongxu Cheng 《Aquaculture Research》2017,48(10):5214-5223
The green algae Haematococcus pluvialis is an important source of natural astaxanthin as feed additive. This study was conducted to investigate the effects of dietary supplementation of H. pluvialis powder on gonadal development, coloration and antioxidant capacity of adult male Chinese mitten crab Eriocheir sinensis, and four experimental diets were formulated to contain 0, 0.2%, 0.4% and 0.6% of H. pluvialis powder. There were four treatments (defined as D1~D4) in this study and each treatment had three replicates. Dietary H. pluvialis contents had no significant effects on survival, body weight gain rate and gonadal development of male E. sinensis. For colour parameters, the total carotenoids content in carapace and hepatopancreas as well as hepatopancreatic lightness (L*) and carapace redness (a*) increased significantly with increasing dietary H. pluvialis (p < 0.05). For the antioxidant indices in the serum, D4 had the lowest activities of superoxide dismutase (SOD) and peroxidase (POD), but the highest glutathione peroxidase (GSH‐Px) and lactic dehydrogenase (LDH), while the malondialdehyde (MDA) in serum and hepatopancreas decreased significantly with the rising content of dietary H. pluvialis (p < 0.05); D1 had the highest levels of SOD, POD and GSH‐Px in hepatopancreas. For the non‐specific immune indices, the highest activities of acid phosphatase (ACP) and γ‐glutamyl transpeptidase (γ‐GT) were found on the serum of D3 and D4 (p < 0.05). D1 had the highest levels of ACP and alkaline phosphatase (ALP) in hepatopancreas, while D2 and D3 had the lowest levels of ALP and ACP respectively. These results suggested the optimal dietary natural astaxanthin level was around 40 mg/kg diets. 相似文献
14.
类胡萝卜素(carotenoid)是影响鱼类体色特性的主要色素,但鱼类自身不能合成这一色素,因此必须从食物中摄入。鱼类类胡萝卜素着色过程涉及对类胡萝卜素的代谢与沉积过程,色素细胞的分化和空间排列,以及与其他色素和色素细胞间的相互作用,这一过程非常复杂,但我们对其机理知之甚少。综述了类胡萝卜素着色效果与鱼类遗传特性、生理状态以及环境因素之间的相关关系,对该研究领域发展趋势进行了讨论和展望,期望为我国研究鱼类体色的形成机制提供一些新的信息。 相似文献
15.
槭树叶呈色机理研究进展 总被引:1,自引:0,他引:1
槭树绚丽多姿、观赏价值高、生态适应性强,可用作庭院树、行道树或景观林树种,在美化城市中发挥着重要作用。文中综述和探讨了槭树叶呈色的生理机理、生态影响因子、花青苷及其合成相关酶在分子生物学方面的研究进展,提出了槭属彩叶植物今后的研究方向,以期为槭树秋色叶变色机理深入研究、叶色改良、新品种育种及其栽培技术提高和园林应用提供参考。 相似文献
16.
降低小麦中多酚氧化酶(PPO)活性,减缓面粉制品的褐化,是重要的育种目标之一。为了更好地服务于低PPO育种,本研究对检测PPO活性的原苯酚染色法进行了优化,更好地发挥了其鉴别力强、结果稳定、对种子活力伤害小等优点,便于育种者使用。苯酚染色和分子标记结果对比发现,染色结果可以很好地反映亲本(或高代)材料中PPO的基因型,特别在低PPO材料中吻合更好。对大量亲本和世代材料的籽粒染色发现,PPO不仅存在于种皮中,其活性还是由种皮基因型决定的,后代PPO性状表现出母性遗传和加性效应的特点,控制高PPO特性的两个主效基因之间具有明显的代偿作用。PPO性状遗传相对简单,纯合较快,F2以后籽粒的染色程度以单株为单位发生分离。尽管染色是针对种皮基因型的,但PPO基因的这些遗传特点和小麦的自交特性,使染色结果同样可以预测后代单株的分离前途。这一优化的籽粒染色法在低PPO育种中的有效性是可以肯定的。 相似文献
17.
Fatime Erdogan 《Aquaculture Research》2019,50(9):2326-2332
This study was carried out to investigate the effects of replacing fish meal with dietary Spirulina as a feed supplement on the growth performance and coloration of blue dolphin cichlids (Cyrtocara moorii). Five isonitrogenous (47% crude protein) and isocaloric (17.36 kJ/g digestible energy) diets were for formulated to replace FM with 0, 5, 10, 15 and 20% Spirulina (designated as Control, SP5, SP10, SP15 and SP20 respectively) and fed to the fish (initial body weight, 3.15 ± 0.01 g). Fish were randomly distributed into fifteen 120 L aquariums (26.5 ± 1.00°C), 15 fish per aquarium. The diets were tested in triplicate for 12 weeks. Experimental groups were fed twice daily (09:00 and 17:00) by hand to satiation. At the end of the feeding trial, significantly (p < 0.05) higher weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER) and lower feed conversion ratio (FCR) were observed in fish fed the SP10 diet when compared to the SP20 diet. There was no significant difference in these parameters between the other groups. The skin coloration of blue dolphin cichlid fed a diet containing Spirulina meal was enhanced. The best coloration was observed in the SP15 group. These impressions were objectively validated by chemical determinations of carotenoids extracted from fish skins and passed statistical tests of significance. The study findings show that Spirulina meal does not diminish growth rates except at very high levels. 相似文献
18.
研究不同浓度茉莉酸甲酯(MeJA)对吐鲁番地区‘克瑞森无核’葡萄果实着色及品质的影响,为合理利用茉莉酸甲酯改善‘克瑞森无核’葡萄果实着色及品质提供参考。以吐鲁番地区‘克瑞森无核’葡萄为试材,于果实着色前和着色初期分别使用不同浓度(20、60、100 mg/L)茉莉酸甲酯喷施果穗2次。采收期测定果实色泽和品质指标,分析不同处理下指标间差异,并通过隶属函数法对果实色泽指标和品质指标进行综合评价,以确定最适宜的施用浓度。结果表明,着色前和着色初期用茉莉酸甲酯处理‘克瑞森无核’葡萄,能够显著提高果皮中花色苷含量、降低叶绿素含量,进而显著提高果实着色指数;处理后的果实红绿色差指标a值、彩度指标C值显著增大,而果面亮度指标L值和黄绿色差指标b值显著降低,果面色泽显著改善;茉莉酸甲酯处理能够显著增大果粒纵径、横径,减小果形指数,增大果粒质量和果穗质量,同时显著增大果梗粗度、可溶性固形物含量、可滴定酸含量。浓度过高会造成果梗耐拉力减小,耐贮运性能下降,可滴定酸含量过高,花色苷含量增幅不大、着色指数不高;而低浓度处理容易出现果粒萎蔫现象。选取与‘克瑞森无核’葡萄果实品质密切相关的15个指标,运用隶属函数法对4个处理的果实品质进行综合评价,果实品质优劣顺序为60 mg/L> 20 mg/L> 100 mg/L> CK。综上,吐鲁番地区于果实着色前和着色初期使用浓度为60 mg/L的茉莉酸甲酯喷施‘克瑞森无核’葡萄果穗2次,可显著改善果实着色,提高果实品质。 相似文献
19.
以氯化铁、硫酸铁、硫酸铜、重铬酸钾、重铬酸钠和高锰酸钾等化学试剂为原料进行桉树单板化学着色的药剂配制,获得16种药剂配方。根据着色处理后试件的着色效果和着色渗透深度,筛选出1种适合桉树单板着色的药剂配方处理,代号PBC-1。以PBC-1为处理药剂,采用多因素正交设计分析常压条件下影响桉树单板着色的因素。结果表明:影响桉树单板着色的各因素主次顺序为:药液浓度>处理时间>药液温度>浴比;桉树单板化学着色最佳工艺参数为:药液浓度0.8%,浴比15∶1,药液温度70℃,处理时间10 h;采用所确定的药剂配方和处理工艺,处理后的桉树单板颜色均匀,呈棕褐色,类似柚木色,并且能够很好克服桉树单板表面因节疤所引起的色差问题。 相似文献
20.
为研究葡萄转色期乙醇处理对葡萄果实成熟进程影响,以"红地球"葡萄为试材,在转色期进行1%氯化钙(CaCl_2)、15%乙醇(EtOH)中溶入1%氯化钙(CaCl_2)、15%乙醇(EtOH)果穗喷施处理,以清水喷施为对照,定期采样测定果实成熟期间单果质量、可溶性固形物(TSS)含量、可滴定酸含量、果实不同部位总酚含量等品质指标的变化以及果实色度角、果皮亮度、叶绿素含量、花青素含量等生理指标的变化。结果表明:15%乙醇(EtOH)中溶入1%氯化钙(CaCl_2)能显著抑制可溶性固形物含量以及葡萄果皮总酚含量的累积,同时延缓了花青素含量的积累以及叶绿素的降解,保持了较高的果皮亮度。15%乙醇(EtOH)中溶入1%氯化钙(CaCl_2)处理能够显著延缓葡萄果实的成熟和着色进程。 相似文献