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101.
102.
以生蚝为原料制备酶解法蚝汁,对比酶解温度、酶解时间及酶添加量对蚝汁感官评分的影响,并以酶解温度、酶解时间和酶添加量为考察因素,利用模糊数学模型结合响应面的方法优化酶解法蚝汁的加工工艺。结果表明:酶解时间对蚝汁的感官评分影响最大,其次是酶解温度,酶添加量对蚝汁感官评分影响最小。确定了酶解法蚝汁最佳工艺参数,即酶解时间3.6 h,酶解温度50℃,酶添加量0.15%。在该优化工艺条件下生产的酶解法蚝汁色泽光鲜,鲜美蚝味突出,鲜蚝香气浓郁,感官评分为85.05,与响应面预测值85.44拟合良好。 相似文献
103.
有机肥和缓控肥替代部分化肥降低双季稻田综合净温室效应 总被引:2,自引:0,他引:2
104.
连续施用土壤改良剂对沙质潮土肥力及活性有机碳组分的影响 总被引:2,自引:0,他引:2
【目的】以河北省廊坊市小麦-玉米轮作区沙质潮土为研究对象,通过2015—2018年田间连续定位试验,研究两种土壤改良剂对土壤活性有机碳组分含量和土壤碳库管理指数的影响,以期为沙质潮土有机碳库培育,改善土壤质量提供理论依据。【方法】试验采用单因素随机区组设计,设4个处理:(1)单施化肥(CK);(2)CK+有机改良剂15 t·hm-2(T1);(3)CK+无机改良剂2.25 t·hm-2(T2);(4)CK+有机改良剂15 t·hm-2+无机改良剂2.25 t·hm-2(T3)。收获季测定土壤有机碳、全氮、pH、速效磷、速效钾,并运用修正的内梅罗指数法计算土壤综合肥力指数(IFI)。再分析活性有机碳各组分含量,并计算碳库管理指数(CPMI)。最后通过CPMI和IFI指示指标评价连续施用土壤改良剂对沙质潮土改良的应用效果。【结果】较CK处理,施用有机改良剂处理土壤总有机碳(TOC)和土壤综合肥力指数(IFI)均显著提高,尤其是有机无机改良剂配施时效果最显著;施用有机改良剂处理各活性碳组分含量均呈升高趋势,并且活性有机碳各组分含量呈现为:易氧化有机碳(LOC)>可溶性有机碳(DOC)>微生物量碳(MBC);施用有机改良剂各处理土壤活性碳库组分有效率均呈下降趋势,T1、T3处理土壤易氧化有机碳有效率(LOC/TOC)较CK分别显著降低了12.57%和12.02%,微生物量碳有效率(MBC/TOC)较CK分别显著降低了12.84%和12.30%,单施无机改良剂处理较CK无显著影响,说明施用有机改良剂增加活性有机碳各组分含量的同时,向土壤中输入了更多的稳定态碳,进而导致有效率的降低;施用有机改良剂各处理土壤碳库指数显著升高、碳库活度显著降低,说明施用有机土壤改良剂能够促进土壤碳库的积累;施用有机改良剂各处理土壤碳库管理指数均呈升高趋势。主成分分析结果表明,施用有机改良剂能够影响土壤中活性碳各组分含量及其有效率。【结论】连续施用有机改良剂能够显著提高沙质潮土肥力,增加土壤碳库管理指数,累积碳库库容,改善土壤质量。 相似文献
105.
泛素结合酶E2是底物泛素化的关键酶,通过泛素—蛋白酶体系统对雌蕊S-RNase进行泛素化和降解,在自交不亲和机制中发挥重要作用。以‘无籽沙糖橘’和‘沙糖橘’的花蕾为试材,以甜橙EST序列EY715921为依据克隆到965bp的cDNA全长序列,其编码152个氨基酸的UBC2蛋白,命名为CrUBC2。在‘无籽沙糖橘’和‘沙糖橘’的编码区发现1个C/T替换,并引起苏氨酸(Thr)变成异亮氨酸(Ile)。多序列比对表明‘沙糖橘’与其他8种植物UBC2仅有1个氨基酸差异,表现出进化中的高度保守性。qRT-PCR分析表明CrUBC2在花药中的表达量最高,异交授粉后的基因表达量是自交授粉的2.22倍~5.36倍,呈现明显的特异表达。体外花粉萌发试验表明,‘无籽沙糖橘’CrUBC2蛋白对自交花粉管生长有明显抑制作用,但对异交花粉管生长无影响,这可能与该蛋白参与S-RNase泛素化并导致异交亲和有关。 相似文献
106.
菜薹硝酸盐积累与品种、营养品质之间的关系 总被引:1,自引:0,他引:1
为获得3种不同颜色菜薹的硝酸盐积累和营养品质间的关系,以绿菜薹(菜心)、白菜薹和红菜薹为试验材料,采用水肥一体化种植和对菜薹的营养品质测定相关方法对不同颜色菜薹的硝酸盐积累与维生素C、可溶性固形物等营养品质间的关系进行研究。结果表明:绿、白和红菜薹不同品种间硝酸盐含量差异显著。硝酸盐聚类分析将44个菜薹品种划分为硝酸盐含量高和低的2个类群:硝酸盐含量高的类群(33个品种)中包括绿菜薹33个品种中的31个品种和白菜薹5个品种中的2个品种;硝酸盐含量低的类群(11个品种)包含2个绿菜薹品种和3个白菜薹品种,另6个红菜薹品种均属于硝酸盐含量低品种。菜薹硝酸盐积累与其营养指标密切相关,根据硝酸盐含量和营养品质指标(包括维生素C、还原糖、可溶性固体物质和蛋白质含量)的聚类分析结果分为3类:第1类包含32个绿菜薹品种和2个白菜薹品种,为高硝酸盐含量和营养品质指数低的品种;第2类包含6个红菜薹品种和2个白菜薹品种,为低硝酸盐含量和营养品质较高的品种;第3类包含1个绿菜薹和1个白菜薹品种,硝酸盐含量低且营养品质佳的品种。PCA分析表明,硝酸盐积累与各营养指标存在差异,且相关性分析也证实硝酸盐与营养指标存在显著相关。菜薹硝酸盐与营养品质分类和相关性分析为筛选和选育低硝酸盐高品质品种奠定基础。 相似文献
107.
108.
【Objective】 Soil fauna is an important component of terrestrial ecosystem, therefore, the studying of the relationship between soil fauna and amendments will help reveal the mechanism of amendments to soil fauna.【Method】During 2016-2019, the characteristics of the soil fauna community in the soil surface layer (0-20 cm) of wheat and maize rotation area with different amendments were investigated. There were four treatments, including no amendment (CK), organic amendment 15 t·hm-2 (YJ), inorganic amendment 2.25 t·hm-2 (WJ) and organic amendment 15 t·hm-2+inorganic amendment 2.25 t·hm-2 (YW). 【Result】During the study period, 4 351 soil fauna belonging to 8 classes, 20 orders, 41 families, and 44 classes were collected, of which 28 families were macrofauna, and the dominant groups were Asilidae and Myrmicinae, accounting for 62.9% of the total captured soil macrofauna. In another, 14 families soil meso-and micro-fauna were collected, and the dominant groups were Acarid and Oribatida, accounting for 93.0% of the total captured soil meso- and micro-fauna. Soil fauna mainly belonged to saprozoic and omnivores. The data indicated that the total number and taxa of soil fauna collected during the experiment was the highest under WJ, and the lowest under YJ. The number of Scutigerellidae, Sejidae and Japygidae decreased and their richness index decreased, while the mites increased, and the dominance index was high under amendments comparing with CK. There were significant differences in individual number and diversity index of small and medium animal communities among different years (P<0.05), and the number of individuals showed a gradually increasing trend; but the Jaccard index (q) of soil fauna was less than 0.50 among all treatments, and the similarity of macrofauna community was lower than that of meso- and micro- community. The ecological niche widths of meso- and micro- soil fauna, such as Acarid, Oribatida, and Onychiuridae, were higher than those of macrofauna, such as Myrmicinae. However, the niche overlap index was higher than 0.97, indicating that the application of amendments increased the common resources of soil fauna. The NMDS analysis showed that the soil animal community in wheat season 2018 was significantly different from that in other years, whereas, in maize season of 2016, 2018, and 2019, there were different. The results of RDA indicated that soil TN and AK were significantly correlated with Acarid, Oribatida, Onychiuridae, Enicocephalidae, Carabidaein wheat season (P<0.05); the soil organic matter and pH were main factors influencing Acarid, Enicocephalidae, Sciaridae, and Asilidae in maize season (P<0.05). The PRC analysis showed that the relative abundance of Uropodidae peaked in October 2017, and that of Asilidae and Myrmicinae peaked in October 2016 under YJ. The relative abundance of Onychiuridae, Acarid, and Oribatida reached a peak in October 2016 under the combined application of organic and inorganic amendments, and that of Phlaeothripidae and Enicocephalidae appeared in 2019 and peaked in October 2019, demonstrating the incongruity of soil fauna groups to the amendments. 【Conclusion】The variation of soil fauna community and diversity in different years were much more profound than amendments, and the amendments modified soil fauna community and diversity mainly by changing soil pH, SOM, and TN in a fluvo-aquic sandy soil. 相似文献
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110.