补灌水平对宁南山区露地青花菜产量、品质及耕层水分动态的影响     

冯海萍  杨冬艳  谢华  裴红霞 《中国瓜菜》2021,(3)

为探究宁夏南部山区自然降水条件下露地青花菜的最佳补灌灌溉方案,采用大田田间对比试验,设置5个补灌水平,在宁夏原州区冷凉蔬菜基地开展补灌水平对土壤水分分布、青花菜产量、品质、水分利用效率的试验研究。结果表明,青花菜全生育期自然降雨主要集中在7月份,且占全生育期降雨量的78.49%,此月份无需补灌即可满足生育后期对水分的需求;不同处理青花菜生育期内土层深度20 cm处土壤含水率总体表现为W5(27mm·667m^-2)>W4(22.5mm·667 m^-2)>W3(18 mm·667 m^-2)>W2(13.5 mm·667 m^-2)>W1(9 mm·667 m^-2),补灌后各处理土壤含水率均达到田间持水量的85%以上;补灌灌溉水平对青花菜花球产量性状、营养品质均有显著影响,W3处理经济总产量最高,达1524.10 kg·667 m^-2,显著高于其他处理6.28%~33.24%;可溶性糖和可溶性蛋白含量也最高,W3可溶性糖含量显著高于W1、W4和W5处理24.46%、12.20%、21.41%,W3可溶性蛋白含量显著高于W135.78%,且可溶性固形物和维生素C质量分数也较高,分别为6.26 g·100 g^-1和9.57 mg·100 g^-1。基于主成分分析的青花菜膜下滴灌最优补灌方案为补灌灌溉定额为69 mm,苗期-莲座期补灌灌水2次,灌水量为33mm,莲座期-球前期补灌灌水2次,灌水量36mm,结球前期-采收期补水主要依靠自然降雨。该结果可为本区露地冷凉青花菜夏季栽培产量的积累与水资源的合理应用提供理论指导。  相似文献   

中微量元素对番茄产量和品质影响的整合分析   总被引：3，自引：0，他引：3  

石如岳  王冲  杨俊雪  于点  高萌萌 《中国瓜菜》2021,(3)

基于已有文献数据讨论了施用中微量元素对番茄单果质量、产量和品质影响的程度,以期为科学施用中微量元素肥料提供依据。研究数据来源于中国知网、万方数据和Web of science,以不施用中微量元素为对照,选择反应比作为效应值,通过Meta分析方法综合分析施用中微量元素对番茄产量和品质的作用效果,并分亚组进行讨论分析。整合分析发现,施用中微量元素能够显著提高番茄果实单果质量和产量,提高比率分别为5.8%、10.2%;显著提高了果实中维生素C和番茄红素含量,提高比率分别为26.3%、69.4%;显著降低了果实中硝酸盐含量达6.7%。综上,施用中微量元素能够显著提高番茄果实单果质量、产量和维生素C含量、番茄红素含量等品质指标,叶面喷施效果优于土壤施用,微量元素效果优于中量元素,且中微量元素施用应以平衡施肥为前提。  相似文献   

国家奶牛良种补贴项目在泾阳县实施的成效与启示     

郭泾利 《中国牛业科学》2011,37(4):59-60,69

为今后奶牛改良工作成果的巩固和推广提供依据,对国家奶牛良种补贴项目在泾阳实施的效果与措施进行总结.结果表明:累计使用良种冷冻精液细管23.7万支,生产改良奶牛3.15万头,且已有1.1万头的优质母牛已正式进入产奶阶段.良种补贴后代奶牛的头胎日产奶量达到27 kg左右,比同期母亲日产奶量高2 kg～3 kg;生奶平均乳...  相似文献   

Does orientation of raft helps in augmenting yield during lean period?: A case study of Gracilaria edulis cultivation in open sea by vertical raft alignment along the south-eastern coast of India     

《Aquacultural Engineering》2016

The food grade agar in India has been almost exclusively obtained from Gracilaria edulis, but the industrial production overwhelmingly relies on exploitation of natural resources. United Nations efforts through Food and Agriculture Organization under Bay of Bengal Program highlighted the necessity of undertaking commercial farming of this species along Indian coast for socio-economic benefits. The pilot-scale experiments established viability of large-scale cultivation by floating raft method. Nevertheless, drastic reduction in yield and quality during summer months due to enhanced sedimentation and severe epiphytism is found to be a major hindrance. Altering the positioning of rafts from horizontal to vertical alignment improved the growth and yield under open sea condition at two different locations along south east coast of India. The average yield in horizontal raft was found to be 3.08 ± 0.61 kg fr wt raft⁻¹ with corresponding DGR of 1.87 ± 0.63% day⁻¹ while same in case of vertical rafts was 13.76 ± 3.86 kg fr wt raft⁻¹ and 5.00 ± 0.5% day⁻¹ in Gulf of Mannar under 45 days growth cycle. The corresponding values along Palk Bay were 2.98 ± 0.52 g fr wt raft⁻¹ and 1.38 ± 0.42% day⁻¹ for horizontal raft and 13.02 ± 6.06 kg fr wt raft⁻¹ and 4.14 ± 1.18% day⁻¹ for vertical raft. ANOVA clearly indicated that raft position significantly influenced the biomass yield and DGR at Palk Bay (F = 75.77; F = 112.81) as well as Gulf of Mannar (F = 27.21; F = 59.16) at p = 0.001. The increment of 1.9–2.6% in fresh weight of individual frond was reported in vertically aligned rafts. The computational fluid dynamics (CFD) based unsteady numerical simulations have confirmed that vertical alignment of raft facilitates relatively free movement of water due to which sedimentation and epiphytism are either minimised or eliminated. Thus these studies can help us to deduce important conclusions pertaining to management of sustained commercial cultivation of this alga in Indian waters.  相似文献   

Recruitment of sympatric vendace (Coregonus albula) and whitefish (C. lavaretus) is affected by different environmental factors          下载免费PDF全文

Arne N. Linløkken  Odd T. Sandlund 《Ecology of Freshwater Fish》2016,25(4):652-663

Vendace and whitefish in Lake Osensjøen (boreal south‐east Norway) were studied by means of gillnet test fishing (1976–2013) and hydro acoustic acquisition (1986–2011). Vendace increased in number between 1998 and 2009 while growth and size at maturity decreased. The relative density of whitefish decreased in the pelagic habitat, whereas growth and size remained the same. Both species exhibited varying year‐class strength. Whereas strong year‐classes of both species became less frequent after 1980 than before this, this seemed to change after 2000, especially for vendace. Generalised additive models suggested a strong positive relationship between July/August mean air temperature and year‐class strength of both vendace and whitefish. Whitefish recruitment was also negatively affected by the new regulation regime implemented since 1981, and positively correlated with water level after hatching and by late ice off. The reason for the diverging impacts of environmental factors on the two species may be that vendace spawn in deeper waters that whitefish do. The results indicate that increasing summer temperatures benefit recruitment of both species, whereas low water level and early ice off will harm whitefish recruitment. Both trends are caused by climate warming. It may be speculated that increased density of the specialised plankton feeding vendace may affect the algal community through increased predation on herbivorous zooplankton and potentially affect the trophic state of the lake.  相似文献   

栽培槽大小对日光温室架式栽培番茄生长发育、水肥利用和产量品质的影响     

张海  李冬  胡莹莹  魏珉  杨凤娟  史庆华  王秀峰 《中国蔬菜》2016,1(8):45-49

利用封闭式循环供液高架栽培系统,研究了栽培槽大小(横切面宽度×深度:20cm×10cm,20cm×15cm,20cm×20cm)和钵栽(直径12cm×高10cm,基质容积1L)对架式栽培番茄(3穗果摘心)生长发育、水肥利用及产量品质的影响。结果表明:与钵栽相比,槽栽促进番茄植株生长,增加产量,但开花和采收时间延迟,果实品质下降,水肥利用效率降低;随着栽培槽体积的增大,植株生长旺盛,干物质积累量增加,但水肥利用效率降低,果实品质下降,不同大小栽培槽处理间水分利用效率和单株产量差异不显著。综合产量、品质及水肥利用效率等指标,番茄架式栽培槽大小以20cm×10cm为宜。  相似文献   

Potential for organic Chilean wine     

Paula Cederberg  Jan-Gunnar Gustafsson 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(1):19-32

Abstract

The potential for extending organic wine production in Chile is discussed in relation to its history and present situation. The main objective is to present an overview of the production of organic wine in Chile, its certification, and national and international markets. During the wine harvesting season in March and April 2006, the authors visited and interviewed staff at four Chilean organic wineries. The wineries were all situated in the wine-producing centre of the country and were of variable sizes. One of the certification bodies in Chile was also interviewed. In addition to the field studies and interviews in Chile, various written information has been used. Second to Argentina, Chile is the country that produces most wine in Latin America. Vineyards cover a total of 110 000 hectares of the country's two million hectares of arable land. A study carried out in 2005 showed that 2000 hectares (almost 2%) of vineyards are organically cultivated. The organic production is operated by 32 different companies, which produce organic wine mainly for exportation to the international market. In Chile, the number of certified organic wine producers has increased in recent years in a trend directed by international demand and possible competitive advantages for Chilean wines. In order for a wine to be called ‘organic’ or ‘wine made from organically grown grapes’, the cultivation and final product must be approved by a certification company. In Chile there are three main active certification bodies; one national (Certificadora Chile Orgánico, CCO) and two international (the Swiss company IMO and the German company BCS). The study reveals a country with innovation and energy but facing strong pressures from the international market and its jungle of laws and directives, and the differing prestige of different certifications and labels. Chile as a wine-producing country has many competitors, and the production of organic wine could be a way to find diversity and exploit new market ground where environmental consideration concerns and sustainability are important targets.  相似文献   

通径分析在油纤兼用亚麻产量分析中的应用     

刘海龙  王世发  周玉萍  牛海龙  刘淑莲  潘亚丽  孙晓平  徐迟 《安徽农业科学》2012,40(11):6416-6417,6419

首先对18个胡麻(Linum usitatissimum Linn.)品系的5个产量构成性状及产量进行相关分析,指出单株粒数和分枝长与产量之间的相关性达显著水平,并且各性状之间还存在着相互作用、相互制约和相互促进的关系。因此对吉林省胡麻产量及其构成性状的关系须采用通径分析方法进行分析,以估算每一个性状对产量的直接作用,以及一个性状通过另一个性状对产量的间接作用。通径分析结果表明,在吉林省提高胡麻产量,可主要通过提高单株粒数和增加分枝数来实现;返青将致使胡麻减产。  相似文献   

大豆新品种中黄30种植密度试验   总被引：1，自引：0，他引：1  

王瑞霞  石爱丽  崔海明  张扬  郭玉炜  胡颖 《河北农业科学》2013,(2)

为了探索大豆新品种中黄30在承德地区的最佳种植密度，试验采用回归设计法，设种植密度18.0万、22.5万、27.0万、33.8万、36.0万和45.0万株/hm 2计6个处理，对不同种植密度下的大豆病虫害发生情况和产量进行了分析；并对其种植密度与产量的关系进行了回归分析，建立了回归方程。结果表明：在试验设定的密度范围内，随着种植密度的增大，大豆虫食率、褐斑病率和紫斑病率均呈先降低后升高的变化趋势，其中密度为22.5万株/hm 2时，3种病虫害的发生率均最低，分别为0.4％、0.5％和0.1％；大豆产量呈先增加后降低的变化趋势，产量与种植密度的二次回归方程为 Y ＝-2731.4259＋358.9022 X-5.0335X 2。本研究条件下，密度为33.8万株/hm 2时大豆产量最高，为3801.667 kg/hm 2。  相似文献   

农民创业过程中基层政府与农民关系的探究     

高山平 《青海农林科技》2010,(1):79-80,65

在国家政策的积极支持下,现在农民创业的热情非常高涨,也有很多成功的案例,但不少基层政府没有很好地理解政策的精神,导致创业过程中农民与基层政府的关系出现了偏差,使得农民不相信基层政府,甚至对有些干部非常反感。本文分析了关系出现偏差的原因并提出了完善的措施。  相似文献