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101.
An experiment was conducted in rice field plots each of 30 m2 to determine the appropriate combination of feeding and fertilization regimes for the giant freshwater prawn Macrobrachium rosenbergii (De Man, 1879) cultured along with rice in rice fields. There were four treatments: rice culture only with regular fertilization (A, control); rice–prawn integrated culture with regular fertilization (B); rice–prawn integrated culture with basal fertilization and commercial feed (C) and rice–prawn integrated culture with regular fertilization and commercial feed (D). Juvenile prawns of 1.5‐g size were stocked on the third day after rice transplantation at a density of 2 prawns m?2 and fed twice daily at 5% reducing to 2% of body weight during the experiment. The rice yield in treatment D (0.42 kg m?2) was significantly higher than that in other treatments (0.34, 0.36, 0.34 kg m?2 in treatments A, B, C respectively). Prawns grew significantly faster (P<0.05) in treatments C and D (23.8±0.9 and 22.0±1.7 g prawn?1 respectively) than in treatment B (14.7±1.6 g prawn?1). Prawn production in treatment C (347±13 kg ha?1 crop?1) was significantly (P<0.05) higher than that (234±30 kg ha?1 crop?1) in treatment B, while in treatment D (296±53 kg ha?1 crop?1) it was not significantly different from that in treatments B and C (P>0.05). Treatment C gave the highest economic returns among all treatments, followed by treatments D and B, indicating that the combination of basal fertilization and commercial feed is the most appropriate nutrient input regime for the rice–prawn integrated culture system. 相似文献
102.
Nobmann JA Blaha T Beyerbach M Kreienbrock L Meemken D 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(7-8):313-319
The German Salmonella Monitoring Programme started by the QS-System in 2002 (Blaha, 2004) is mandatory due to the so-called "Salmonella Regulation for Pigs" since 2007 (Anonym, 2007). The Regulation does not clearly prescribe the specific muscle which is to be taken as source of the meat juice. Thus, at different slaughter plants meat samples are also taken from different muscles and several scientific papers describe various muscles as source of the meat juice, too. The objective of this study was to compare the serological results of meat juices from three different locations (diaphragm pillar, neck, belly muscle) to each other and to those of the blood serum from exactly the same animals. All samples were simultaneously tested for Salmonella antibodies by two serological tests (Salmo-type Pig Screen, LDL, Germany; HerdChek Swine Salmonella, IDEXX, Germany). Comparisons were carried out between the various sample kinds per animal and between the two test systems. The analysis of all results of the meat juices revealed in both test systems a clear decline of the OD% values from the diaphragm pillar to the neck to the belly muscle. The average OD% values of all samples were higher when measured by the HerdChek ELISA (IDEXX, Germany) than by the Salmotype ELISA (LDL, Germany), especially in blood serum. Since the results of the meat juice samples gained from the diaphragm pillar were in both test systems by far the closest to the results of the corresponding serum blood samples, it is recommended to amend the "Salmonella Regulation for Pigs" by prescribing meat from the diaphragm pillar as the only muscle for gaining meat juice. 相似文献
103.
为了解染色体易位对小麦农艺性状的影响,以豫农982(1BL/1RS易位系)和wheatear(7DL.7Ag易位系)杂交后代的900个F2群体及其F2∶3家系为实验材料,对F2群体进行1BL/1RS易位和7DL.7Ag易位类型的分子检测,并对F2群体及F2∶3家系的主要农艺性状进行田间调查(F2群体的农艺性状仅作参考,重点分析F2∶3家系的农艺性状)。结果表明,(1)STS标记Lr19130与SSR引物Xgwm428联合使用可作为共显性标记鉴定纯合与杂合的7DL.7Ag易位,完善了7DL.7Ag易位的分子检测方法;(2)1BL/1RS易位可显著降低株高,提高穗粒数与小穗数;(3)7DL.7Ag易位在籽粒千粒重和饱满度上有显著的正向作用,但7DL.7Ag易位的穗粒数显著低于非7DL.7Ag易位,且有延迟小麦成熟和增加株高的趋势;(4)1BL/1RS和7DL.7Ag双重易位可同时提升小穗数和千粒重,但穗粒数减少。 相似文献
104.
为开展麦类作物功能基因组学研究,选用综合性状突出的大麦品种Tamalpais,通过化学诱变剂甲基磺酸乙酯(Ethyl methane sulfonate,EMS)处理,创建了含有10 389个M2单株的突变群体。该群体数据分析表明,温室条件下,6.21%的M2幼苗呈现叶片颜色变异;大田实验中,M2群体出现丰富的表型变异,主要包括幼苗匍匐、分蘖、株高、生育期、叶色、叶形、叶条纹、叶斑、穗部特征、育性等,其中幼苗匍匐、分蘖、株高、叶色、叶条纹、叶斑的突变频率分别为0.11%、6.03%、0.13%、2.5%、0.18%、0.17%。抽样调查显示,M2世代的胚坏死率较低,仅有9%左右的单株表现出过半的胚坏死率。运用TILLING技术成功获得大麦COI1同源基因的突变体,筛选结果同时表明,该突变群体的突变频率约为平均每673kb一个点突变。因此,Tamal-pais群体突变表型丰富、TILLING检测可行,可作为麦类作物基因图位克隆与功能验证的重要素材,适用于麦类作物的正向和反向遗传学研究。 相似文献
105.
黄淮麦区小麦品种春化光周期基因型及其与产量性状的相关性 总被引:1,自引:0,他引:1
为了解新品种的春化和光周期基因的显隐性组成及对产量的影响,以2011-2012年度国家冬小麦品种区域试验黄淮南片的42个小麦品种为材料,用STS标记对Vrn-A1、Vrn-B1、Vrn-D1、Vrn-B3四个春化基因和光周期基因Ppd-D1位点进行检测,并结合供试材料的农艺性状,探讨春化基因显隐性组成与品种的冬春性、抽穗期及产量性状的相关性.结果表明,42个小麦品种均含有光周期非敏感型等位变异Ppd-D1a.各显性春化基因中,Vrn-D1的出现频率和含有其的品种(系)数最高(38.1%和16);Vrn-A1与每穗小穗数呈显著负相关;Vrn-B1与抽穗期呈显著正相关,与每穗小穗数和产量呈显著负相关;Vrn-D1与抽穗期呈极显著正相关.在春化基因组合中,vrn-A1+ vrn-B1+ vrn-D1与抽穗期呈极显著负相关,与每穗小穗数呈显著正相关;Vrn-A1+vrn-B1+vrn-D1与每穗小穗数呈显著负相关;vrn-A1+ vrn-B1+ Vrn-D1与抽穗期呈显著正相关.说明在小麦可以正常成熟的前提下,对产量等性状有正向作用的最佳春化基因型组合为Vrn-A1+vrn-B1+ vrn-D1. 相似文献
106.
植物蛋白饮料配方优化研究 总被引:4,自引:0,他引:4
采用均匀混料设计对以大豆、花生、核桃为原料的植物蛋白饮料进行配方试验,采用消费者总体接受性评定值及单位成本为指标进行配方优化。结果表明:当核桃浆、花生浆、大豆浆含量分别为0.31861,0.60838,0.07301时,消费者接受性最大为7.13,单位成本为2.25元/L;根据成本结合消费者接受性进行配方比较选择,实验表明当核桃浆、花生浆、豆浆的含量分别为0.16367,0.55157,0.28476时,其消费者接受性与前面的最优配方并无显著的差异,成本较低,为1.55元/L。 相似文献
107.
家兔与大鼠胫骨前肌的生后发育 总被引:1,自引:1,他引:0
为探讨家兔、大鼠胫骨前肌在生后各日龄阶段前、后亚体内快慢肌纤维的发育情况,应用大体解剖结合组织化学法明确其肌亚体,并作琥珀酸脱氢酶(SDH)染色,图象分析两型肌纤维的直径特征。用电生理记录仪,分别测量肌前、后亚体功能。结果表明:家兔与大鼠各肌亚体划分在生后发育中逐渐分界清楚,生后2、3天均未能分出Ⅰ、Ⅱ型肌纤维,也未见有原始肌束。Ⅰ、Ⅱ型肌纤维比例随年龄增长而变化,Ⅱ型纤维比例增大。Ⅱ型纤维直径均大于Ⅰ型纤维,葡萄状运动神经末梢支配慢肌纤维,斑点状运动终板位于快肌纤维,前后肌亚体诱发电位表明其特殊的功能。 相似文献
108.
Thanh H. Dao 《Biology and Fertility of Soils》2014,50(1):155-167
Long-term nutrient management practices have lasting effects on the geographic distribution of soil microorganisms, loci of enhanced activity, and non-mobile nutrients such as phosphorus (P) to ultimately influence nutrient use efficiency by crops and edge-of-field losses. We determined the distribution of soil microbial biomass, phosphomonoesterases' activity, and P forms in a 10-ha no-till field that received annual additions of dairy manure at 0, 15, and 30 kg P ha?1 at the field scale for 16 consecutive years. The spatial structure of soil microbial indices and extractable P fractions were characterized based on their semivariance distributions for each manure treatment. The buildup in soil P occurred, although replacement was done at a crop removal rate. Manure additions resulted in overall mean increases in total labile P of 73 % and 156 % and alterations in the soil microbial ecosystem that depended on manure inorganic-to-enzyme-labile P composition in soils treated with 15 and 30 kg P ha?1, respectively. Distinct clusters of phosphate- and enzyme-labile organic P were observed within manure treatments, where accumulation of the latter forms was associated with high soil microbial biomass C and reduced acid phosphomonoesterase activity. The geographic variability highlighted the critical need for improving methods of field-scale application of manure and non-mobile nutrients. In addition, current soil testing methods that depend upon composite representative samples for estimating microbiological parameters linked to nutrient turnover and P requirements for optimal crop production should be modified to include site-specificity in sampling and interpretation approaches. 相似文献
109.
饲料中锰未添加组的草鱼生长和饲料效率降低,畸形率增加,随着饲料中锰含量的增加,椎骨中锰含量也逐渐增加。当饲料中锰添加量到15mg/kg饲料以上时,椎骨锰含量达到最大并趋于相对稳定。锰未添加组草鱼的比肝重,肝脂量明显高于锰添加组,锰未添加组血浆中破性磷酸酶活性比锰添加组高,而草鱼血浆中红细胞,血红蛋白;红细胞压积,红细胞体积,红细胞平均血红蛋白量,红细胞平均血红蛋白浓度,血浆总蛋白,血浆葡萄糖等,不受饲料中锰含量的影响。综合本试验结果,草鱼时饲料中锰的最适需要量为15mg/kg饲料为宜。 相似文献
110.
陕西几种主要土壤脲酶热力学特征初探 总被引:1,自引:0,他引:1
计算陕西省 7种土壤 19个不同肥力土样的脲酶热力学参数结果显示 ,土壤脲酶的ΔG≠ >0、Δ H≠>0、ΔS≠ <0 ,反映出酶促反应不能自发进行 ,必须由外界供给能量 ,才能克服位阻上的障碍 ;除水稻土外 ,其余土样脲酶的Δ G≠ 值低肥力土样大于高肥力 ,Δ H≠ 和ΔS≠ 值变化不明显 ,相关分析等揭示出土样脲酶ΔG≠ 与土壤肥力中的有机质呈显著相关 ,各热力学参数的平均值也呈现出一致的规律性变化 相似文献