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1.
氮素水平对甜菜干物质积累分配和产糖量的影响   总被引:3,自引:0,他引:3  
论述了不同氮素水平下,甜菜植株干物质积累与分配的规律,及其与道理形成的关系。指出了施氮量与块根含糖率呈极显著的负相关,r=-0.993^**,而施氮量与块根产量和单位面积产匀呈二次曲线相关。  相似文献   

2.
本研究的目的是明确在适宜的和不适宜的土壤氮素条件下,生长季节中叶面施氮肥对甜菜块根产量,产糖量、块根质量和氮吸收的影响。  相似文献   

3.
合理的甘蔗氮肥施用量能减少蔗田由于过量的化学肥料投入而造成的生态破坏。本文于2017~2019年通过1新1宿田间定位试验研究了不同施氮量对甘蔗农艺性状、产量、糖分等的影响。试验在崇左龙州县设置了6个不同施氮量处理,分别为施纯氮0、225、300、375、450、600(常规施氮量)kg/hm~2。甘蔗伸长期采用叶绿素仪测定叶片SPAD值和氮素含量,收获期测定甘蔗产量、锤度、株高、茎径等性状。结果表明:施用氮肥能使甘蔗产量和产糖量显著增产,施氮量为300 kg/hm~2(N2)时甘蔗产量和产糖量最大,1新1宿平均产量和产糖量分别为80296、10889kg/hm~2。不同施氮处理对甘蔗糖分则无显著影响,但当施氮量低于225kg/hm~2后,宿根年的产糖量将显著下降。在甘蔗氮素利用方面,施氮能提高伸长期叶片SPAD值和氮含量;氮肥农学利用率、氮肥偏生产力、氮肥产糖力随着氮肥的增加而逐渐下降。"线性+平台"模型能完整地模拟产量与氮肥的肥效关系。龙州县河谷地区甘蔗生产上推荐的氮肥施用量为300~375kg/hm~2,这比常规施肥减少了37.5%~50%的氮肥用量,同时能稳定甘蔗的后续生产,这对节省甘蔗生产成本和减少农田面源污染有着重要意义。  相似文献   

4.
施肥水平对甜菜产糖量的影响   总被引:1,自引:1,他引:0  
研究了甜菜生产力的适宜施肥水平,结果表明甜菜单位面积产量、产糖量与施肥量间呈二次曲线相关,以N10P12K10(kg/亩)处理的甜菜产量、产糖量最高,在此施肥量范围内,甜菜产量随施肥产量增加而提高,再增加施肥量进则降低甜菜生产力。  相似文献   

5.
锌对甜菜产质量及生理效应研究   总被引:1,自引:0,他引:1  
经在黑龙江省甜菜主产区进行的田间小区,盆栽试验和多点大区取样分析,表明:1)较高的土壤供锌水平,可提高甜菜各器官的锌含量,施锌0.4kg/亩可获得最高的甜菜块根产量和产糖量,2)甜菜施锌可降低块根中有害灰分的含量,改善甜菜的工艺品质;3)适宜的土壤辞素营养,可以提高甜菜的抗热抗旱、抗涝和抗寒性。  相似文献   

6.
钾对甜菜主要营养的影响   总被引:3,自引:0,他引:3  
试验研究表明,甜菜各器管的相对含钾量,随生育进程呈降低趋势。叶和叶柄中的绝对含钾量呈单峰曲线变化,峰值分别出现在7月中旬和8月中旬左右。块根的绝对含钾量至状获时达到最高水平。各器管的绝对含钾量均随施钾量的增加而提高。钾对氮的吸收有促进作用,即氮与钾配合施用有利于产量的形成。  相似文献   

7.
施氮量对翠碧1 号生长发育及烟叶质量风格的影响   总被引:4,自引:1,他引:3  
通过田间试验和化学分析,研究了不同施氮水平对翠碧1 号烤烟生育期、烤后烟叶产质量和烟叶风格的影响。结果表明,不同施氮量对烤烟生育期、经济性状、外观质量、化学成分和感官评吸质量均有显著的影响。施氮量增加,烟株大田生育期明显延长;烤后烟叶产量、不同部位单叶重、总氮和烟碱含量明显增加,总糖和还原糖含量、还原糖/烟碱和总氮/烟碱比值表现下降的趋势;烟叶“清香型”风格彰显趋向弱化。施氮量大于78 kg/hm2 时,烤后烟叶产值增加不显著;施氮量在58.5~97.5 kg/hm2 时,烟叶内在化学成分较协调,外观质量和感官评吸质量较好,烟叶“清香型”风格彰显较明显。  相似文献   

8.
施氮量与留叶数对万源晒红烟产质量和香气成分的影响   总被引:2,自引:0,他引:2  
为探究施氮量与留叶数对万源晒红烟产质量和香气成分的影响,以主栽晒红烟品种"万毛3号"为材料,设计不同施氮量与留叶数的栽培试验,对晒红烟农艺性状、经济性状和香气成分等进行测定分析。结果表明,随施氮量和留叶数增加,万毛3号的产量和产值上升,均价和上、中等烟比例先升高后降低。施氮量增加,烟叶的烟碱、钾含量显著上升,糖含量显著下降;中性致香成分总量显著升高,多种质体色素降解产物、苯丙氨酸转化产物和茄酮含量上升。留叶数增多,烟叶糖和钾含量显著升高,烟碱、总氮含量下降;中性致香成分总量和新植二烯、类胡萝卜素降解产物含量呈下降趋势,而苯丙氨酸类转化产物和棕色化产物含量显著上升。综合分析,在施氮15 kg/667 m2、留叶18片处理下,烟叶的产量较高,品质较优,感官质量评价好。  相似文献   

9.
氮素水平对甜菜主要营养的影响   总被引:2,自引:1,他引:1  
甜菜植株含氮量与施氮量呈极显著正相关,生育中前期氮的分配以叶部为主,其后氮向根的分配率增加,但高氮处理到生育后期氮对叶部的分配率仍处于较高水平,不利于产量形成和糖分积累。甜菜植株磷、钾含量与施氮量呈极显著正相关,氮与磷、钾表现出明显的互作效应。  相似文献   

10.
水分胁迫下施氮量对烤烟生理特性及化学成分的影响   总被引:5,自引:3,他引:2  
采用盆栽试验研究了水分胁迫下施氮量对烤烟生理特性及化学成分的影响.结果表明,在中度干旱下(相对含水率50%)随施氮量增加,烤烟根系活力增强,叶片脯氨酸含量、超氧化物歧化酶(SOD)活性及光合速率明显升高,丙二醛含量无明显差异;轻度干旱条件下(相对含水率65%),烤烟团棵期和成熟期缺氮或氮素水平过高,烤烟根系活力、SOD酶活性及光合速率均明显降低,丙二醛含量增加,脯氨酸含量变化不大,在烤烟旺长期和现蕾期烤烟根系活力、SOD酶活性,丙二醛及脯氨酸含量均随施氮量增加明显升高.在中度和轻度干旱下随施氮量增加,上部叶和中部叶总氮、烟碱及蛋白质含量呈增加趋势,总糖、还原糖含量呈下降趋势,糖碱比、氮碱比、施木克值以纯N 7 g/株的中氮肥处理较合理.在同一施氮水平下,中部叶和上部叶总糖和还原糖含量随着土壤含水率的增加而增加,烟碱、总氮以及钾含量均有所降低,糖碱比、氮碱比、施木克值以轻度干旱较适宜.  相似文献   

11.
Owing to their health benefits, probiotics and prebiotics are nowadays widely used in yogurts and fermented milks, which are leader products of functional foods worldwide. The world market for functional foods has grown rapidly in the last three decades, with an estimated size in 2003 of ca US$ 33 billion, while the European market estimation exceeded US$ 2 billion in the same year. However, the production of probiotics and prebiotics at industrial scale faces several challenges, including the search for economical and abundant raw materials for prebiotic production, the low-cost production of probiotics and the improvement of probiotic viability after storage or during the manufacturing process of the functional food. In this review, functional foods based on probiotics and prebiotics are introduced as a key biotechnological field with tremendous potential for innovation. A concise state of the art addressing the fundamentals and challenges for the development of new probiotic- and prebiotic-based foods is presented, the niches for future research being clearly identified and discussed.  相似文献   

12.
常用消毒灭菌法及其机理与应用   总被引:3,自引:0,他引:3  
傅金泉 《酿酒科技》1999,(2):97-99,101
介绍了采用消毒灭菌方法,有加热消毒法,紫外线辐射法和化学药剂消毒法。常用化学药剂有醛类、含氯消毒剂、醇类消毒剂以及高锰酸钾、生石灰等,阐释了消毒与灭菌两个概念的区别。  相似文献   

13.
益生素、益生菌与结肠癌   总被引:1,自引:0,他引:1  
介绍了益生素和益生菌及其作用机理。在动物模型中,有大量的数据证实益生素和益生菌能够预防癌症.而在人体内还没有直接实验证据。它们抑制癌症的确切机理目前尚不清楚,其抑制机理可能是:肠道菌群代谢活动的改变,肠道理化环境的改变,潜在的致癌物质的黏附和降解,肠道菌群的改变、抗癌或抗诱变物质的形成、提高宿主的免疫应答、影响宿主的生理活动以及发酵不能被消化的食物并形成有益代谢产物。  相似文献   

14.
节能节水型印染助剂和设备的现状   总被引:1,自引:0,他引:1  
从节能、节水、缩短工艺流程和环保的角度出发,介绍了国内外研制开发的一系列新型节能、节水型印染助剂和染整设备。  相似文献   

15.
原花色素及其开发应用   总被引:9,自引:0,他引:9  
对原花色素的结构、化学特性、制备、分析方法、应用前景作一综述,并重点讨论其生理功能,为在功能性食品、药物、化妆品等领域的深入研究和开发提供参考。  相似文献   

16.
天然香精香料是高价值的精细化工产品和食品添加剂,但原料来源有限且提取成本高。利用生物技术生产这类产品具有广阔的前景。简述了发酵工程、酶工程、细胞工程和基因工程在香精香料中的应用,并探讨了生物技术在香精香料中的应用前景。  相似文献   

17.
毛霉型低盐速成豆豉工业化生产工艺与设备   总被引:1,自引:0,他引:1  
本文介绍了毛霉型低盐速成豆豉的工业化生产工艺及生产线的关键设备。  相似文献   

18.
This paper presents the combined mid-term findings of the consumer research components of two EU Sixth Framework Programme integrated projects concerning meat, ProSafeBeef and Q-PorkChains. The consumer pillar of ProSafeBeef carried out eight focus group discussions in May 2008, in France, Germany, Spain and the UK. Q-PorkChains conducted a large-scale, web-based, consumer survey in January 2008 in Belgium, Denmark, Germany, Greece and Poland. The first project provides a set of qualitative data from a small cohort of focus groups and the second a set of quantitative data from a larger consumer sample. This paper draws together the main findings of both projects and provides a comprehensive overview of European citizens’ and consumers’ attitudes towards and preferences regarding beef and pork. In general, consumers consider meat to be a healthy and important component of the diet. Consumers support the development of technologies that can improve the health attributes of meat products and guarantee eating quality, but they have a negative view of what they see to be excessive manipulation and lack of naturalness in the production and processing of beef products. In the Q-PorkChains study consumer and citizen segments are identified and profiled. Consumer segments were built upon the frequency and variety of pork consumption. The citizen segments were built upon their attitudes towards pig production systems. Overall, the relationship between individuals’ views as citizens and their behaviour as consumers was found to be quite weak and did not appear to greatly or systematically influence meat-buying habits. Future studies in both projects will concentrate on consumers’ acceptance of innovative meat product concepts and products, with the aim of boosting consumer trust and invigorating the European beef and pork industries.  相似文献   

19.
The objectives of the current study were to investigate the relationship between body condition score (BCS) and dairy form and changes in genetic parameters for BCS and dairy form within and across lactations and age. Body condition score and dairy form were obtained from the Holstein Association USA, Inc. Records were edited to include those cows classified between 24 and 60 mo of age and between 0 and 335 d in milk (DIM). A minimum of 20 daughters per sire and 15 cows per herd-classification visit were required. The dataset consisted of 135,178 records from 119,215 cows. Repeatability, multiple trait, and random regression models were used to analyze the data. All models included fixed effects for herd-classification visit, age within lactations 1, 2, and 3 or higher, and 5th-order polynomials for DIM. Random effects included sire and permanent environment for all models. Random regression models included age at classification nested within sire or DIM and lactation number nested within sire. Genetic variance for both BCS and dairy form was lowest in early lactation and highest in midlactation. Genetic correlations within and across lactations were high. The genetic correlation between DIM 0 in lactation 1 and DIM 305 in lactation 3 was estimated to be 0.77 for BCS and 0.60 for dairy form. The genetic correlation estimate between 30 mo of age at classification and 50 mo of age at classification was 0.94 for both dairy form and BCS. The repeatability models appeared to generate accurate evaluations for BCS or dairy form at all ages and stages of lactation.  相似文献   

20.
酚类物质的结构与性质及其与葡萄及葡萄酒的关系   总被引:20,自引:0,他引:20  
酚类物质是一类大而复杂的化合物。葡萄与葡萄酒中常见的酚类物质可分为类黄酮和非类黄酮两大类,它们是葡萄中重要的次生代谢产物,与葡萄的抗病性、采后生理、贮存、保鲜等密切相关。葡萄酒中的酚类物质来自于葡萄果实、果梗、酵母代谢以及橡木桶,参与形成葡萄酒的味道、骨架、结构和颜色等,对红葡萄酒的特征和质量尤其重要。  相似文献   

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