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71.
Ibrahim Wasiu Arolu Mohd Y. Rafii Marhalil Marjuni Mohamed M. Hanafi Zulkefly Sulaiman Harun A. Rahim Mohd Isa Zainol Abidin Mohd Din Amiruddin Ahmad Kushairi Din Rajanaidu Nookiah 《Euphytica》2017,213(7):154
In practice, progeny and individual palm selection are believed to be the most suitable breeding approach for improvement of quantitative traits in oil palm because their phenotypic expressions are strongly influenced by abiotic factors. Therefore progeny selection approach was applied in this study for the selection of high fresh fruit bunch (FFB) and dwarf oil palm planting materials. Cross between Deli dura and Nigerian pisifera resulted into 34 D × P full sib progenies with 1036 seedlings. For six consecutive years, data were collected on yield and yield component traits, while vegetative traits were recorded once. Bi-parental analysis was carried out using analysis of variance, followed by progenies mean comparison, variance components, heritabilities and cluster analysis. Highly significant (P ≤ 0.01) progeny effect was recorded in this study and this had a pronounced effect on the expression of all the quantitative traits. Progenies performance of FFB varied significantly and it ranged from 166.49 to 220.06 kg/palm/year (kg/p/yr) with trial mean of 192.93 kg/p/yr. Palm height after 8 years of field planting ranged from 1.67 to 2.78 m (control cross) with trial mean of 2.12 m. Broad sense heritability (\({\text{h}}_{\text{B}}^{2}\)) was found to be very low (<17.60%) for all the yield traits, however this parameter was high for vegetative traits with palm height having \({\text{h}}_{\text{B}}^{2}\) of 90%. Cluster analysis based on all the quantitative traits grouped all the 34 DP progenies into nine distinct clusters. From this study, five progenies (DP3, DP4, DP5, DP8 and DP24) were identified to be high yielding and dwarf palms compare to trial mean. At density of 140 palm/ha, they will produce FFB of 28.63–30.81 t/ha and average of 29.69 t/ha which is about 27.15% higher in FFB when compared to the current planting material with FFB of 23.35 t/ha. In addition, the selected progenies possessed average annual palm increment of 29.82 cm/yr with range of 26 and 32.5 cm/yr which was 57.33% shorter than the current planting material with palm height increment of 45–75 cm/yr. 相似文献
72.
73.
设计了简便可行的光度滴定装置;探讨了光度滴定法同时测定酱油中游离酸和游离氨基氮的测定条件。结果表明,此法操作简便、快速,有良好的重现性和精密度。用该法测定酱油中的游离酸和游离氨基氮,取得了回收率分别为99.4% ̄103%和97.3% ̄101%、变动系数分别为2.2% ̄2.8%和0.39% ̄1.4%的良好效果。经t检验,用本方法测定酱油中游离酸和游离氨基酸不引起系误差,并且测定结果与我国国家标准方法 相似文献
74.
Tolga Dinçer Asli Cadun Ilker Aydın Cengiz Metin Sukran Cakli 《Journal Of Aquatic Food Product Technology》2013,22(4):378-385
Tissue distribution of polyphenol oxidase (PPO) was studied in caramote prawn (Melicertus kerathurus) and jinga shrimp (Metapenaeus affinis) postmortem. Activity was analyzed in different tissues: the head (cephalothorax + carapace), carapace, exoskeleton of the abdomen, pereopods, and maxillipeds, individually. Based on the results, PPO activity of jinga shrimp was determined to be higher than caramote prawn during the research period. Partial tissue distribution showed that the highest activity was determined in carapace by using 70% ammonium sulfate fractions. Partial tissue distribution was also used to determine the spread of black spots. In addition, comparison between the PPO levels of caramote prawn and jinga shrimp was performed. The importance of these species is their economic value. However, there is no available data in the literature about caramote prawn and jinga shrimp. The determined data showed us that using antioxidant chemicals would be suitable for jinga shrimp. 相似文献
75.
P. Udén 《Journal of animal physiology and animal nutrition》2011,95(1):27-33
A novel macro in vitro system was used to test the theory that rumen proportions of acetate, propionate and butyrate are not representative of their respective net production rates. Whole rumen content (10–16 kg) from two cows was mixed with a bicarbonate buffer and incubated separately in two 40‐l in vitro vessels for 3 h. A total of six experimental periods were used. In this study, a total of six cows were used and fed 1/8 of the daily ration by hand every 3 h. To obtain differences in rumen volatile fatty acids (VFA) composition, 1 l of acetate (416 mm ), propionate (108 mm ), butyrate (79 mm ), lactic acid (300 mm ) or nothing was infused during 24 h into the rumen before collection of representative samples of rumen contents. Infusions of acids were then continued during the in vitro incubations in exact proportion to the digesta removed from the rumen. In Periods 1 and 2, the cows were alternatively infused with acetate or nothing. In Periods 3 and 4, the infusions consisted of propionate or butyrate and in Periods 5 and 6 of lactate or nothing. Nine liquid samples were obtained between 3 and 180 min after the start of incubation and analysed for concentrations of VFA. Changes in proportions of individual VFA were estimated by linear regression. No differences in VFA proportions were observed in the absence of infusion (p > 0.5) over time, but when individual VFA were infused, their respective proportions increased. This was interpreted as the result of a decreased in vitro fermentation rate of digesta substrates compared with that in the rumen. Lactate infusion increased butyrate proportion in vitro. It is concluded that this study could not provide any evidence that ruminal VFA proportions are unrepresentative of the proportions of net production. 相似文献
76.
水稻植株生长模型的研究 总被引:5,自引:0,他引:5
研究了早稻茎数消长和叶龄增长,以及叶面积增长和抽穗率的变化,分析了叶龄与积温,氮肥水平及茎数之间的关系,以及不同类型品种间分蘖力的差异,分别组建了叶龄与积温,茎数的数学模型,不同施氮量与茎数消长的数学模型,以及叶面积增长和始穗率数学模型。结果表明,早稻常规品种的茎数消长主要与叶龄增长的关系密切,同时受品种的分蘖力潜能,总叶片数以及不同施氮量的影响,叶龄增长主要与积温有关,而与施氮量关系不明显。 相似文献
77.
Zhongwu Wang Shuying Jiao Guodong Han Mengli Zhao Walter D. Willms Xiying Hao Jian’an Wang Haijun Din Kris M. Havstad 《Strength and Conditioning Journal》2011,64(3):249-256
Livestock performance is a critical indicator of grassland production systems and is influenced strongly by precipitation and stocking rates. However, these relationships require further investigation in the arid Desert Steppe region of northeastern China. We employed a randomized complete block design with three replications and four grazing treatments (nongrazed exclosure [Control]), lightly grazed [LG], moderately grazed [MG], and heavily grazed [HG]) by sheep in a continuously grazed system (June to November), to test the effect of stocking rate on sheep performance. The planned stocking rates were 0, 0.15, 0.30, and 0.45 sheep · ha?1 · mo?1, for the control, LG, MG, and HG treatments, respectively. However, actual stocking rates were calculated for each paddock in each year based on a 50-kg sheep equivalent (SE). Annual net primary production (ANPP) was determined at peak standing crop in August 2004 to 2008. Live weight gain was determined for the summer and fall periods, as well as the total grazing period, in each year. ANPP decreased with increasing stocking rate, and daily live weight gain per head decreased linearly with increasing stocking rates over the total grazing period but in a quadratic manner over the summer period with a plateau at the lower rates. Maximum sheep production per unit area over the total grazing season occurred at about 2 SE ha?1 for about a 5-mo grazing period, but individual gains per sheep were predicted to decline after about 1 SE ha?1 presumably because of forage limitations. However, in order to achieve stable annual production, we recommend that the Desert Steppe be grazed at about 0.77 SE ha?1 for a 5-mo period (0.15 SE ha?1 · mo?1). This estimate is based on published grazing strategies that consider an average ANPP with a recommended utilization rate of 30%. 相似文献
78.
研究了沟埂工程及地面覆盖物对棉花的生物学效应。结果表明,沟埂工程能明显改善土壤水分状况,0~50cm上层的土壤含水量较对照提高2%~5%左右;对棉花的农艺性状和经济性状均呈正效应,果枝数、现蕾数、有效铃数均比对照有较大幅度的增加,百铃重增加0.05kg,667m ̄2增产皮棉7.9kg,增产率为15.02%;叶片总含水量、自由水含量显著高于对照,各处理叶片总含水量与0~15cm土壤含水量呈显著正相关,束缚水含量与土壤含水量呈负相关;比叶重明显增加,叶组织电导率低于对照。地面覆盖物对保持土壤水分有一定效应,保水剂处理效应不明显。 相似文献
79.
断奶仔猪料中添加甲酸钙、杆菌肽锌及高铜的效果 总被引:4,自引:0,他引:4
试验采用L9(34)正交设计,将35日龄断奶的27窝仔猪共207头,以窝为单位分成9组。试验因子为3个不同水平的甲酸钙(0,1,2%),杆菌肽锌(0,63,126万效价单位/吨),及铜(0,75,1500ppm)。45~75日龄期间进行饲养试验。结果表明,在45~75日龄期间,添加甲酸钙极显著影响(降低)猪的平均日增重(P<0.01)和经济效益;添加杆菌肽锌有利于仔猪的平均日增重,且以添加63万单位/吨为宜。加铜后不显著影响猪的平均日增重(P<0.1)。建议45~75日龄期间不再添加酸化剂。 相似文献
80.
重庆市畜禽粪便排放时空分布研究 总被引:12,自引:4,他引:12
以重庆市直辖前(1995、1996年)和直辖后(2000、2001年)畜禽养殖数据为基准,研究重庆市各区(市、县)畜禽的年粪便排放量,并从时间和空间上分析重庆市畜禽粪便年排放量的变化趋势。结果表明,1995、1996、2000、2001年畜禽粪尿总排放量为7455.03万t、7831.56万t、7223.84万t、7421.52万t;猪粪当量分别为6954.84万t、7419.62万t、6433.5万t、6748.02万t;畜禽粪便中平均年有机质排放量为794.45万t、N43.27万t、P23.36万t、K45.51万t。重庆市畜禽粪便负荷、猪粪当量负荷和有机质、N、P、K负荷分布以近郊为重,而畜禽粪便年排放量、猪粪当量及有机质、N、P、K量却是位于三峡库区的区、县量较大;直辖前后畜禽粪便年排放量及猪粪当量、猪粪当量负荷、N、P、K排放总量及负荷相差不明显。 相似文献