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11.
本文围绕2023年7月登陆我国华南沿海的2304号“泰利”热带气旋,利用CMA-STI热带气旋最佳路径数据集、NCEP/NCAR再分析I资料、NOAA每日(非插值)OLR资料,对登陆台风“泰利”在广西地区的暴雨增幅进行了特征分析。结果表明,登陆后的“泰利”被副热带高压、大陆高压、切断低压及副高延伸的高压脊包围,这样的环流形势有利于环流维持;“泰利”活动期间越赤道气流明显增强,索马里急流和80-90°E的越赤道气流在南海北部海域交汇后,将大量的水汽、动量和潜热能量注入登陆“泰利”环流,使其登陆后仍能维持一段时间;2023年7月第4侯,西南季风处于活跃期,触发低纬西南季风涌北传并侵入“泰利”环流,进而在广西地区产生暴雨增幅。此外,低层热力条件特征也是导致“泰利”暴雨增幅的重要原因。  相似文献   
12.
巨胚杂交稻的农艺及产量性状   总被引:2,自引:0,他引:2  
以2个巨胚不育系及其相应的2个非巨胚不育系,3个巨胚恢复系、2个非巨胚恢复系为材料,配制一套共20个半双列杂交组合,研究巨胚(ge)基因对杂交稻的若干生物学特性的影响。结果表明:ge基因对杂交稻主要农艺性状和部分产量性状没有显著影响,但ge基因使杂交稻的千粒重、容重、理论产量和实际产量下降,且只有在纯合时才有显著表达。含杂合geGE基因也使其上述性状有所下降,但幅度明显小于gege纯合基因。  相似文献   
13.
介绍燕麦的营养价值及其市场前景,阐述法库县在土质、气候、地理环境、人文环境等方面种植燕麦的条件优势,通过对比种植燕麦与玉米的经济收益,探索燕麦在法库县种植的潜力。  相似文献   
14.
水稻物质生产特性及其与产量的关系研究   总被引:3,自引:0,他引:3  
以汕优63、Ⅱ优162、Ⅱ优419、K18A/149和65002为材料,在云南省涛源乡、宾川县和杭州市富阳县进行试验,分析了水稻高产的物质生长特性,并比较了不同环境下物质生长特性的差异及原因。结果表明:云南涛源和宾川产量分别比杭州高80%和66%,导致云南产量较高的主要原因是生物产量较高。生物产量差异主要在幼穗分化以后,尤其是灌浆结实期。在云南生态条件下,中后期能容纳较高的叶面积系数(LAI),群体生长速率(CGR)较高,使花后物质生产量大,且花后物质运转量也较高。  相似文献   
15.
通过梯度饲养、消化代谢和比较屠宰试验,综合评定了籽粒苋籽实粉对星布罗(Star-bro)肉仔鸡的营养价值和对日粮氨基酸利用率的影响.结果测得籽粒苋籽实粉含可消化粗蛋白质132.75g/kg,表观代谢能13.44MJ/kg;日粮中纳入16%苋籽实粉,显著提高了氨基酸利用率和血浆游离赖氨酸、亮氨酸及甘氨酸浓度,日粮粗蛋白质和能量代谢率分别提高6.91%和5.33%,日粮中营养物质转化为胴体蛋白质、脂肪的效率及料肉比均得到改善.  相似文献   
16.
In semi-arid Mediterranean areas, small grain aftermath stubble represents an important summer source of food for grazing flocks of small ruminants. Wheat stubble is a mediocre source of forage and flocks are grazed in summer under harsh conditions of temperature and air dustiness. However, stubble grazing procedures are changing, water and shading are more frequently available between grazing sessions (“improved management”), and the biological soundness of this ancestral practice needs to be re-visited. The present study was aimed at evaluating the cost in energy of “improved” wheat stubble grazing, compared with feeding a similar diet indoors. The intake of stubble was first quantitatively and qualitatively evaluated in Awassi sheep. Ewes consumed daily 980 ± 100 g day− 1 of wheat stubble. Ewes were then housed and fed diets consisting of wheat hay, straw and grain formulated to be iso-energetic and iso-nitrogenous to diets consumed from wheat stubble. The average intake of ME was similar during the confinement and the pasture periods (6.4 ± 0.5 and 7.6 ± 0.8 MJ day− 1of ME, respectively). During 2 days of each period, animals were fitted with external electrodes and data loggers of heart rate and skin temperature. Energy expenditure (EE) was calculated from oxygen consumption estimated as the product of heart beats rate measured for the two days by the amount of oxygen delivered to body tissues at each heart beat (O2 pulse). The O2 pulse was determined by simultaneously measurement of oxygen consumption and HR twice daily on two occasions, while grazing stubble and indoors. Energy expenditure and energy balance were not different in sheep while grazing wheat stubble (11.1 and − 3.5 MJ day− 1) or fed indoors (11.1 and − 4.8 MJ day− 1). Our data show that stubble did not cover nitrogen and energy requirements for maintenance, and that the cost of summer stubble grazing carried out under conditions described here is less than thought before.  相似文献   
17.
Although there is an extensive database on the nutrient content of conventionally produced feedstuffs, there is very little published research on the nutrient content of feedstuffs that are organically grown. Industrial and organic crop production differ in both crop and soil management. There are data to suggest that these differences may result in differences in the nutrient content of organic grown feedstuffs. The purpose of this study was to determine the ME content of organically grown amaranth, buckwheat, white corn, yellow corn, and wheat samples obtained from the University of Minnesota's organic research farm. Both chickens and turkeys were used in the assays to compare the ME content for these 2 species. The TMEn content, on an as-fed basis, of amaranth, buckwheat, yellow corn, white corn, and wheat for chickens were found to be 3,146, 3,072, 3,603, 3,324, and 3,592 kcal/kg, respectively. The TMEn content of the same samples, on an as-fed basis, determined with turkeys were found to be 2,748, 2,227, 2,810, 2,757, and 2,959 kcal/kg, respectively. True ME content of the organically grown feed ingredients was found to be greater when chickens were used in the bioassay as compared with turkeys and differed significantly from published values for the same cereals grown using conventional means.  相似文献   
18.
This experiment was conducted to investigate the effect of soybean meal replaced by brewer's grain (BSG) or fermented brewer's grain (FBSG) on growth performance,immune organ index and intestinal flora of meat geese.A total of 250 geese at 28 days of age were randomly assigned to 5 groups with 5 replicates per group and 10 geese per replicate.The geese in control group were fed a basal diet (with soybean);The geese in groups 1 and 2 were fed the basal diet with the 10% and 20% BSG replacing the soybean,respectively;The geese in groups 3 and 4 were fed the basal diet with the 10% and 20% FBSG replacing the soybean,respectively.The whole experiment period was 42 days,including three phases:15 d (early stage),14 d (middle stage) and 14 d (later stage).The results showed as follows:①From the whole experiment period,compared with control group,the ADG of geese in group 1 was significantly increased (P<0.05),the ADG and ADFI of geese in group 4 were significantly decreased (P<0.05),there were no obvious change in growth performance of geese in groups 2 and 3 (P>0.05).② Compared with control group,the thymus index and spleen index of geese in groups 1,2 and 3 were extremely significantly increased at early stage (P<0.01);At middle and later stages,the spleen index of geese in group 2 were significantly and extremely significantly increased (P<0.05;P<0.01);There were no significant differences in bursa of fabricius index of geese among all groups (P>0.05).③ Compared with control group,the number of Escherichia coli and Salmonella in cecum in groups 1 and 2 were extremely significantly decreased at early and later stages (P<0.01),while the number of Bifidobacteria and Lactobacillus were increased in different degrees;the number of Bifidobacteria and Lactobacillus in cecum in groups 3 and 4 were extremely significantly increased at later stage (P<0.01).In conclusion,10% BSG replacing soybean in the basal diet could improve the growth performance and intestinal flora of meat geese;10% FBSG replacing soybean in the basal diet could promote the growth of beneficial bacteria of meat geese,but had no effect on growth performance;While 20% replacing soybean in the basal diet could decrease the feed intake and weight gain of meat geese,hinder its growth and development.  相似文献   
19.
水稻(Oryza sativaL.)是我国主粮作物之一,稻米镉污染对我国粮食安全造成一定威胁.镉低积累水稻品种的选育可有效降低水稻籽粒镉污染风险,高效准确的镉积累相关分子标记在镉低积累水稻品种选育中具有至关重要的作用.以水稻微核心种质为材料,基于籽粒镉积累关联基因的功能性SNP位点开发了KASP分子标记LCd-38.选...  相似文献   
20.
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