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71.
Many of 450 common wheat cultivars bred and registered during the twentieth century in 12 countries were proved, due to seed-by-seed analysis, to be composed of two or more biotypes differing in their alleles at the gliadin (Gli) loci. These multiple biotypes may be regarded as authentic progeny of the respective parent lines, as evidenced by the gliadin composition of the respective parents. Therefore, the official claim for each cultivar to be uniform is commonly not maintained in practice. The most frequent was a non-uniform cultivar composed of two biotypes differing at one Gli locus, but there were cultivars represented by a large set of related genotypes differing at several Gli loci. The proportion of the multi-biotype cultivars was never less than 15% for a country collection, exceeding 50% in other countries. This proportion differed significantly between neighbouring countries. In Australia, all multi-biotype cultivars were found in eastern states; in the state of Victoria, their frequency was statistically higher than in the rest of the country. The proportion of multi-biotype cultivars among newly-released cultivars decreased with time in Australia and the UK. Thus, the non-uniformity of registered cultivars represents a general and important phenomenon of common wheat as a crop.  相似文献   
72.
73.
Mastitis is a common reproductive disorder in bitches, reaching a prevalence of 0.71%. Mastitis has a wide range of forms, from asymptomatic to severe gangrenous mastitis that can lead to septic shock and death of the bitch and nurslings. However, most of the time it is overlooked, undiagnosed or mistreated. The present systematic review was performed to revise and summarize the existing knowledge related to this disorder, including diagnosis, treatment and prevention.  相似文献   
74.
Protein Z is a major component in beer foam. Two-dimensional electrophoresis was used to analyze wort proteins of two Australian (Buloke and Commander) and two Canadian (CDC Meredith and Bentley) varieties. The Canadian barley contained more abundant proteins from MW 40–45 kDa (pI 5 to 7). These proteins were identified as either protein Z4 or protein Z7 using liquid chromatography–mass spectrometry. Full-length gene of protein Z4 and Z7 were sequenced from Canadian and Australian barleys. Sequence differences were identified in the coding region and upstream regions of the two genes, resulting in protein sequence and expression variations. Molecular markers were designed according to the indels in the upstream regions of protein Z4 and Z7 genes. These markers were highly correlated to wort protein Z content in Canadian and Australian varieties. The Canadian barleys contained ‘high level’ genotypes for protein Z4 and Z7 while most Australian barleys had ‘low level’ genotypes for protein Z4, Z7 or both. The markers identified in this study provide a valuable tool for the selection of protein Z alleles in marker-assisted breeding. Total protein Z content was assessed using different steeping conditions, and increasing air-rest time increased protein Z content in 15 varieties.  相似文献   
75.
赵小刚  张蒙蒙  刘钰婷  戴思兰 《园艺学报》2020,47(Z2):3033-3034
小菊新品种‘东篱小太阳’是以‘东篱娇粉’为母本,A42为父本进行杂交,经5年选择培育而成。株形较大,自然成球,自然开花期集中在9月中下旬到10月中下旬,半重瓣,舌状花为鲜亮的红色,可满足北京地区国庆用花的需求。  相似文献   
76.
Quantifying the amount of carbon (C) incorporated from decomposing residues into soil organic carbon (CS) requires knowing the rate of C stabilization (humification rate) into different soil organic matter pools. However, the differential humification rates of C derived from belowground and aboveground biomass into CS pools has been poorly quantified. We estimated the contribution of aboveground and belowground biomass to the formation of CS in four agricultural treatments by measuring changes in δ13C natural abundance in particulate organic matter (CPOM) associated with manipulations of C3 and C4 biomass. The treatments were (1) continuous corn cropping (C4 plant), (2) continuous soybean cropping (C3), and two stubble exchange treatments (3 and 4) where the aboveground biomass left after the grain harvest was exchanged between corn and soybean plots, allowing the separation of aboveground and belowground C inputs to CS based on the different δ13C signatures. After two growing seasons, CPOM was primarily derived from belowground C inputs, even though they represented only ∼10% of the total plant C inputs as residues. Belowground biomass contributed from 60% to almost 80% of the total new C present in the CPOM in the top 10 cm of soil. The humification rate of belowground C inputs into CPOM was 24% and 10%, while that of aboveground C inputs was only 0.5% and 1.0% for soybean and corn, respectively. Our results indicate that roots can play a disproportionately important role in the CPOM budget in soils. Keywords Particulate organic matter; root carbon inputs; carbon isotopes; humification rate; corn; soybean.  相似文献   
77.
从粮食作物、经济作物及饲草的种植,饲草料的加工调制与利用,全舍饲肉羊的养殖及杂交繁育,以及羊粪尿的资源化利用等方面介绍了豫北山区“粮—草—羊”高效平衡养羊模式发展现状,以期为促进豫北山区资源可持续利用、山区生态环境良性循环和社会经济可持续发展提供思路。  相似文献   
78.
莱豆新品种龙莱1号的选育   总被引:1,自引:0,他引:1  
征集龙岩市莱豆地方品种13个,按照育种目标进行品种筛选、提纯、繁殖、特征特性观察与栽培技术试验,育成的莱豆新品种龙莱1号具有中熟、品质优、产量高、抗病性较强、适应性广、商品价值高等特点。该文介绍该品种从2003~2010年的选育过程及该品种主要特征特性。  相似文献   
79.
兴安盟春玉米生产现状及生态气候应对措施   总被引:2,自引:0,他引:2  
在深入基层调查和多年实践经验基础上,总结了兴安盟玉米生产中存在的主要问题,并提出了应对措施。结果认为,兴安盟玉米生产中存在的主要问题是没有充分利用气候资源实现高产稳产,玉米越区种植和浪费热量资源问题突出,并提出了合理利用气候资源趋利避害的应对措施和建议,对稳定兴安盟玉米单产、提高玉米总产具有重要意义。  相似文献   
80.
The mung bean variety Ji Heilv No.12 was bred by lnstitute of Characteristic Crop Research, Chongqing Academy of Agricultural Sciences and lnstitute of Food and Oil Crops, Hebei Academy of Agricultural and Forestry Sciences. using Jilv 9 and Jilv 7 as female and male parent respectively,with pedigree method. Ji Heilv No.12 is a new variety with features of high and stable yield,broad adaptability and strong resistance in yield trails during 2011-2012; it was approved and released by Chongqing Provincial Committee of Crop Variety ldentification in 2012,suitable for cultivating in most area of Chongqing.  相似文献   
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