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161.
A significant effect of year on maize nutritive value has been reported in many studies; however, the direct effect of year on both nutritive values and fermentation traits of maize silage has not been directly investigated. During a 7‐year period (2006–2012), we investigated the following variables of 597 maize silages commercially produced in bunker silos on farms in the Czech Republic: dry‐matter content (DM), crude protein (CP), starch, amylase‐treated neutral detergent fibre (aNDF), acid detergent fibre (ADF) and net energy lactation (NEL), as well as fermentation traits such as pH, contents of lactic acid (LA), acetic acid (AA), butyric acid (BA) and the ratio between LA and volatile fatty acids. The effect of year and DM explained 16 and 30% of the variability in nutritive and fermentation traits respectively. Although a common silage DM content was used for each year, the climatic effect of year significantly changed almost all tested variables, but particularly aNDF, ADF, starch, AA and BA. The year contribution to trait variability effect was as much as two times higher for fermentation traits (12·6%) as for nutritive value (6·1%). Temperature–precipitation relationships associated with achieved maize yield were considered as factors explaining the year effect. Temperature and precipitation averaged over the full vegetation period had low relevance to nutritive and fermentation traits. This study reveals the importance of year‐to‐year variation in silage nutritive value and fermentation, which could be useful for understanding the contribution of year to these changes in both field experiments and national assessments. 相似文献
162.
Tree-specific management practice related to individual tree physiological condition is necessary for higher quality and quantity in apple fruit production. Detection of apple flowering abundance based on analysis of HSL (hue, saturation, luminance) images was used to estimate the number of flower clusters (FC) of individual trees in a high density apple orchard. The image acquisition was performed with a still camera and an industrial color camera during the day and night. The FC estimation algorithm included HSL thresholding with parameter optimization. Three hypothetical, tree-specific management practices (sprayings) were assumed, using >25, >50 and >100 FC thresholds to carry out the practice. When an industrial camera was used for image acquisition during the daytime and hypothetical spraying was done by on/off criterion >100 FC per tree, 10 % incorrect executions were identified. Comparable FC counting performance was achieved by using a still camera or an industrial camera. 相似文献
163.
实时定量PCR(qRT-PCR)是分析功能基因表达水平的常用方法之一,qRT-PCR数据统计分析离不开合适内参基因的选择。为了选择中国小麦花叶病毒(Chinese wheat mosaic virus, CWMV)侵染条件下的小麦内参基因,本实验通过PCR扩增效率和扩增特异性分析,从10个持家基因中选择8个候选基因,然后以接种CWMV的小麦样品为材料,利用qRT-PCR技术进一步检测上述8个基因在CWMV侵染条件下小麦样品中的时空表达特性。基于这些数据,通过geNorm、NormFinder程序分析,结果表明,2个小麦基因(即26S和CDC)在CWMV侵染前后以及不同组织中表达最为稳定,26S和CDC组合可选作CWMV与小麦互作过程中功能基因表达分析的内参基因。 相似文献
164.
本文根据灰色系统理论,选用区分毛叶石楠和小叶石楠及其变种的20个植物标本的各个鉴定性状资料,采用灰色聚类分析法,对毛叶石楠和小叶石楠及其变种进行了定量分类。结果表明,计算分类与比较形态分类结果相一致,而且该方法计算简便,实用性好,为植物分类提供了一种新的定量分类方法。 相似文献
165.
Ana Barbič 《Agriculture and Human Values》1998,15(3):253-265
Cultural identity of rural areas is discussed with some basic concepts such as culture, territory, contemporary globalization, and individuation processes. This case study of cultural identity in the Slovenian countryside focuses on its spiritual culture, of which several components are presented in detail: the language of rural areas, (handy)crafts, nutrition and food culture, co-operation and mutual help among rural residents at work and in leisure, and the art products of Slovenian farmers. In discussing the present status and the future of rural cultural identity, the danger of idolizing (romanticizing) traditions for the sake of selling them to tourists is pointed out and the necessity of traditions being part of everyday life of rural residents stressed. As a part of work and leisure life of rural residents, traditions are constantly changing due to local as well as to international socio-economic processes, to inner and outer stimuli to keep existing traditions and to create new ones. 相似文献
166.
167.
Shah Mujahid Ali Saito Taiju Šindelka Radek Iegorova Viktoriia Rodina Marek Baloch Abdul Rasheed Franěk Roman Tichopád Tomáš Pšenička Martin 《Fisheries Science》2021,87(1):71-83
Fisheries Science - The cleavage pattern of a vertebrate’s embryo is either holoblastic (complete) or meroblastic (partial). Sturgeon and other basal bony fishes represent a transition of the... 相似文献
168.
Golpour Amin Broquard Coralie Milla Sylvain Dadras Hadiseh Baloch Abdul Rasheed Saito Taiju Pšenička Martin 《Fish physiology and biochemistry》2021,47(3):703-711
Fish Physiology and Biochemistry - The aim of this study was to evaluate seasonal testicular development in the cultured sterlet, Acipenser ruthenus. During annual sexual cycle of male sterlet,... 相似文献
169.
170.
Marek Šmejkal Marie Prchalová Martin Čech Mojmír Vašek Milan Říha Tomáš Jůza Petr Blabolil Jan Kubečka 《Ecology of Freshwater Fish》2014,23(3):405-413
Fish associations with different types of littoral habitats were studied in four canyon‐shaped reservoirs in the Czech Republic in years 2010 and 2011 by gillnets. Two to three habitats per reservoir–beaches (former meadows), stump fields (former forest) and rubble slopes–were defined and sampled along the longitudinal axis of reservoirs. Effects of reservoir, habitat and locality (position along longitudinal axis) on fish biomass, abundance and species structure were tested for juvenile and adult fish separately. Hierarchical analysis of variance revealed that habitats differed significantly in fish biomass and abundance. Redundancy analysis showed that analysed environmental variables had significant influence on fish community structure. Most variability in community structure was explained by reservoir and then by combination of habitat and slope steepness. Locality position had the smallest influence on community structure. For both adult and juvenile fish total abundance and biomass, the most inhabited habitat was beaches; rubble slopes were the least inhabited. Habitat associations differed among species. Among adults, bream Abramis brama, white bream Blicca bjoerkna and roach Rutilus rutilus were associated with beaches and stump fields, whereas perch Perca fluviatilis, ruffe Gymnocephalus cernuus, asp Aspius aspius and pike Esox lucius were associated with rubble slopes. Bream, white bream, bleak Alburnus alburnus, roach, ruffe and pikeperch Sander lucioperca were associated with beaches among juveniles, whereas the only juvenile associated with rubble slopes was perch. We showed that most common species are associated with distinct habitats and also that utilisation of various littoral habitats differs in general. 相似文献