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Χ灾绷吹矸酆康挠跋焓钦?,直接影响比间接影响大。Study on the correlation between rice quality and agronomic traits of quality riceNIE Cheng rong, WEN Yu hui, WANG Yun bo, CHEN Ming zhong,LI Mei, LIU Dao quan(Agronomy Department, Foshan University , Nanhai 528231,China)The correlative analy  相似文献   
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Some Physical Properties of Linseed   总被引:1,自引:0,他引:1  
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1. An experiment was conducted to determine the effect of different dietary protein contents on the performance of naked neck (Na/na) and normally feathered (na/na) broilers.

2. Chicks from the two genotypes were reared in wire‐floored cages and divided at random into 3 groups. Birds were fed on high protein (HP, 12.99 MJ ME, 238 g crude protein/kg and 12.94 MJ ME, 216 g crude protein/kg from 0 to 3 and 3 to 7 weeks, respectively), medium protein (MP, 12.99 MJ ME, 219 g crude protein/kg and 12.87 MJ ME, 201 g crude protein/kg from 0 to 3 and 3 to 7 weeks), and low protein (LP, 12.94 MJ ME, 205 g crude protein/kg and 12.75 MJ ME, 184 g protein/kg from 0 to 3 and 3 to 7 weeks) diets.

3. The LP diets resulted in a significantly lower daily body weight gain of males from 0 to 3 weeks. Dietary protein content had no effect on body weight gain from 3 to 7 weeks, body weight at 7 weeks, and the food intake of birds. Carcase composition of birds from both genotypes was unaffected by dietary protein.

4. Naked neck birds had significandy higher body weights at 7 weeks. Yields of carcase and breast of Na/na males were significantly higher than those of na/na males. There were no significant differences between females from the two genotypes as regards carcase yield.

5. It was concluded that the dietary protein requirements of naked neck birds were similar to those for normally feathered birds.  相似文献   

5.
Isozyme analysis and sequence analysis of the internal transcribed spacer regions (ITS-1 and ITS-2) and the 5.8S subunit of the ribosomal DNA gene repeat were used to examine whether isolates of Phytophthora porri from Allium and Brassica represent a single homogeneous species. Twenty-six strains of P. porri, 16 strains isolated from the genus Allium, and 10 strains isolated from the genus Brassica, were analyzed using malate dehydrogenase (MDH), isocitrate dehydrogenase (IDH) and lactate dehydrogenase (LDH), represented altogether by four putative loci (Mdh-2, Idh-1, Idh-2, and Ldh-2). Isozyme analysis revealed that strains isolated from Allium contained five private alleles at three isozyme loci (Ldh-2 83, Ldh-2 104, Idh-1 108, Idh-1 112, and Idh-2 98), whereas six different alleles were observed at four isozyme loci (Ldh-2 85, Ldh-2 100, Ldh-2 114, Idh-1 100, Idh-2 100, and Mdh-2 111) in strains obtained from Brassica. The heterozygosity at the Ldh-2 locus, differing in allele composition, however, between strains from Allium and Brassica, was present in all strains, indicating that it is probably fixed. Sequence analysis of the ITS regions and the 5.8S subunit showed consistent differences between isolates from Allium and isolates from Brassica. Based on isozyme data, ITS sequence analysis and formerly published differences in restriction enzyme patterns of mitochondrial DNA, morphology and pathogenicity, it was concluded that the isolates of P. porri Foister did not represent a homogeneous species. Isolates from Brassica constitute a distinct species which is described here as P. brassicae sp. nov. It was inferred from isozyme patterns, which were in no case intermediate between the two species, that P. porri and P. brassicae do not hybridize and are reproductively isolated by barriers to gene flow.  相似文献   
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Plant Foods for Human Nutrition - St. John’s wort has been used for centuries in traditional medicine of many cultures, and nowadays it is well-known as a clinically important antidepressant...  相似文献   
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The need for a better understanding of the interaction between irrigation practices and the elevation and quality of the water table is of paramount importance for developing irrigation management strategies to ameliorate the regional problems of elevated saline water tables in the San Joaquin Valley, California. An area of approximately 3000 ha which includes portions of the Diener Ranch and the adjacent University of California, Westside Research and Extension Center, located south of Five Points in the Westlands Water District on the west side of the San Joaquin Valley was chosen for extensive field measurements. Field work consisted of four main activities namely, field instrumentation, collection of records of field activities, periodic data collection, and analyses of field data. Field measurements of water table carried out during 1994 indicated that the water table elevation was sensitive to the irrigation practices. There was a general increase in the area with a water table close to the surface during the irrigation season, and a return to water table elevations similar to the starting conditions at the end of the season. During the study period, the surface water quality deteriorated more in areas irrigated with reuse water and persisted through the end of the season. Depth averaged electrical conductivity for the study area over 6.5 m decreased between December 1993 and December 1994. Vertical hydraulic gradients in the saturated zone, were found to be an order of magnitude larger than horizontal gradients. The direction of vertical gradients changed, with downward gradients following pre-irrigations and upward gradients later in the season, when crop water requirements increased. Based on the results of the field study, it can be concluded that the irrigation management practices have a direct effect on local water table response as well as on water quality. Therefore, irrigation practices that promote less deep percolation losses may be helpful in controlling the water table rise.  相似文献   
8.
平江县位于湖南省东北部,是一个典型的"老、山、边、穷、大"五位一体的农业大县,也是国家级贫困县。近几年来,平江县农业综合开发办公室不断总结经验教训,努力探索农业综合开发的新途径,逐步完善有关政策,使平江县农业综合开发迈上了一个新的台阶。  相似文献   
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苹果蠹蛾[Laspeyresia pomonella(L.)]是世界上为害苹果和梨的主要蛀果害虫,被许多国家和我国列为植物检疫对象。该虫在我国现仅分布于新疆。英联邦昆虫研究所(Common-wealth institute of entomology,C.I.E.)(1951,1976)根据陈方洁、王飞鹏(1936)及胡经甫(1938)的记述,将我国浙江(奉化)、河北、湖北、东北三省(辽宁、吉林、黑龙江)、北平(北京)及新疆等8个省、市、自治区划分为该虫分布区,从而严重影响我国苹果及梨的出口和外销。为了查清该虫在我国的分布情况,首先核对并纠正 C.I.E.制图所依据的上述两篇文章的错误,同时在张从仲等(1984—1985)在山东、辽宁等8省市大面积进行的苹果蠹蛾性诱剂监测的基础上,于1991年4—10月在山东、辽宁、河北苹果和梨主要产区及出口基地继续进行苹果蠹蛾性诱剂监测、果园调查及剖果检查,结果均未发现苹果蠹蛾成虫或幼虫。到目前为止,此虫仍局限分布于我国新疆。  相似文献   
10.
草地早熟禾新品种特异性、一致性和稳定性测试指南初报   总被引:3,自引:0,他引:3  
在系统调研国内外文献,广泛收集草地早熟禾种质,连续2年温室幼苗性状评估,连续3年田间性状评价和广泛征求专家意见的基础上,首次编制了我国草地早熟禾特异性、一致性和稳定性(DUS)测试指南。指南在形式与主要内容上,与国际植物新品种保护联盟(UPOV)的草地早熟禾测试指南相协调,包括测试的总体技术要求、性状表、性状解释和技术问卷4部分;在性状与标样品种确定上主要参照了UPOV和日本的测试指南。  相似文献   
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