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1.
[目的]研究2016年的江西省国家级开发区的土地利用集约情况,为未来开发区的土地集约利用方向提供建议。[方法]采用多因素分析法从土地利用状况、利用效益和管理绩效3个方面构建评价指标体系,对江西省20个国家级开发区土地集约利用水平进行评价和分析。[结果]得到江西省20个国家级开发区的土地集约利用综合评价分值,并进行排序。[结论]江西省国家级开发区土地集约利用程度基本为集约度较高和集约度中等。 相似文献
2.
[目的]查找水稻RSSG58在拟南芥中的同源基因并观察其组织表达模式。[方法]利用相关基因信息学网站构建水稻RSSG58的基因进化树,构建其同源基因ATG58::GUS定位载体转入拟南芥,观察分析ATG58的组织表达模式。[结果]进化树和序列对比发现ATG58与RSSG58具有较高的序列相似性,GUS定位遗传材料显示ATG58在多种组织都有表达,在生长发育早期的根、子叶、下胚轴、胚芽表达量相对较高,在生殖发育阶段的花苞和花药内优势表达,ATG58与RSSG58具有相似的GUS定位组织表达模式。[结论]ATG58是水稻RSSG58的同源基因,二者组织表达模式一致,这些结果为深入研究拟南芥ATG58和水稻RSSG58在雄配子发育过程中的作用及机制提供了基础资料。 相似文献
3.
[目的]筛选适宜栽培的黄瓜嫁接砧木。[方法]对4种黄瓜砧木与津优4号黄瓜接穗品种进行嫁接栽培试验,以黄瓜自根苗为对照(CK),研究了不同砧木嫁接对黄瓜生长发育、抗病性、品质及产量等的影响。[结果]黑籽南瓜砧木嫁接黄瓜植株的成活率最高(95.0%);4种砧木嫁接均能显著降低发病率,其生长势、产量均显著优于自根苗,但品质与自根苗无显著差异。[结论]黑籽南瓜砧木嫁接黄瓜在成活率、生长势、抗病性、品质和产量等方面表现优异,适宜作为黄瓜嫁接砧木进行推广。 相似文献
4.
Megan M. Mathey Sonali Mookerjee Lise L. Mahoney Kazim Gündüz Umesh Rosyara James F. Hancock Philip J. Stewart Vance M. Whitaker Nahla V. Bassil Thomas M. Davis Chad E. Finn 《Euphytica》2017,213(5):112
Ten seedlings from 36 crosses representing eastern and western North American short day and remontant genotypes were evaluated in 2011 and 2012 in California, Michigan, New Hampshire and Oregon, for phenology, flower related traits, plant characteristics, fruit characteristics and fruit chemistry traits. There was significant variability among genotypes, locations and evaluation year for most of the characteristics; however, few genotype × location and genotype × year interactions were detected. General combining ability variance components were significant for all traits and greater than SCA variance components for peduncle length, total flowering weeks, flowering cycles, truss size, growing degree days for harvest data, remontancy, achene position, ease of capping, fruit weight, percent soluble solids, titratable acidity and soluble solids/titratable acidity. ‘Sarian’ was identified as the best contributing parent for remontancy. Narrow-sense heritability estimates were moderate to high (0.33–0.78) for total flowering weeks, flowering cycle, truss size, remontancy, number of runners, fruit weight, pH, and titratable acidity. Having a better understanding of these attributes will provide breeders guidance on the most effective breeding strategies for incorporating superior traits from this germplasm into their programs. 相似文献
5.
Replicate allocation to improve selection efficiency in the early stages of a potato breeding scheme
M. F. Paget P. A. Alspach J. A. D. Anderson R. A. Genet W. F. Braam L. A. Apiolaza 《Euphytica》2017,213(9):221
Field data and simulation were used to investigate replication within trials and the allocation of replicates across trial sites using partial replication as an approach to improve the efficiency of early-stage selection in a potato breeding programme. Analysis of potato trial data using linear mixed models, based on four-plant (clonal) plots planted as augmented partially-replicated (p-rep) designs, obtained genetic and environmental components of variation for a number of yield and tuber components. Heritabilities, trial-to-trial genetic correlations and performance repeatability of clonal selections in p-rep trials and in subsequent fully replicated trial stages were high, and selection was effective for the economically important traits of marketable tuber yield and tuber cooking quality. Simulations using a parameter-based approach, pertaining to the variance components estimated from the p-rep field trials, and the parametric bootstrapping of historic empirical data showed improved rates of genetic gain with p-rep testing over one and two locations compared with testing in fully replicated trials. This potato breeding study suggests that the evaluation and selection of a clonal field crop in fully replicated trials may not be optimal in the early stages of a breeding cycle and that p-rep designs offer a more efficient and practical alternative. 相似文献
6.
Karolina Tremmel-Bede László Láng Kitti Török Sándor Tömösközi Gyula Vida Peter R. Shewry Zoltán Bedő Marianna Rakszegi 《Euphytica》2017,213(12):291
Improving the nutritional quality and health benefits of food has been of increasing interest globally over the last decade. Staple cereal foods are the major sources of dietary fiber and a recent study identified the Chinese wheat cultivar Yumai-34 as having unusually high levels of water-extractable arabinoxylan (WE-AX) and total arabinoxylan (TOT-AX) in flour. Crosses were therefore made between this variety and three Central European varieties (Lupus, Mv-Mambo, Ukrainka) and the physical properties (test weight, thousand-kernel weight, flour yield, kernel hardness), composition (protein, gluten, WEAX, total AX) and processing quality (gluten index, Zeleny sedimentation, Farinograph parameters) of the grain were compared for thirty-one breeding lines (F7–F9) and the four parents in a 3-year field experiment (2013–2015). Increases of 0.5% in the WE-AX content and 1% in the content of total AX content of the flour were achieved, with an improvement in dough properties. The thousand-kernel weight, protein content, gluten content, Zeleny sedimentation and water absorption of the flour also increased in many lines, while three of the lines had yields that were competitive with the official control varieties, making them suitable for registration. 相似文献
7.
8.
Tobias Würschum Hans Peter Maurer Sigrid Weissmann Volker Hahn Willmar L. Leiser 《Plant Breeding》2017,136(2):230-236
Genomic prediction has emerged as a powerful genomic tool to assist breeding of complex traits. In this study, we employed a population of 647 triticale doubled haploid lines derived from four families to assess the potential of this approach for triticale breeding. All lines were phenotyped for grain yield, thousand‐kernel weight, biomass yield, plant height, frost tolerance and Fusarium head blight resistance. The obtained prediction accuracies were moderate to high and consisted to varying degrees of within‐ and among‐family variance, in line with the different degrees of phenotypic differences between family means. The prediction accuracy within individual families also varied with the genetic complexity of the traits and was generally highest based on effect estimation with lines from the respective family, whereas the prediction accuracy decreased with decreasing relatedness among the families. Taken together, our results illustrate the potential of genomic prediction to increase selection gain in triticale breeding, but the composition of the training set is of utmost importance, and consequently, the implementation of this approach in applied breeding programmes is not straightforward. 相似文献
9.
Marker‐assisted backcrossing to develop foliar disease‐resistant genotypes in TMV 2 variety of peanut (Arachis hypogaea L.) 下载免费PDF全文
Rohini M. Kolekar Mallenahally Sukruth Kenta Shirasawa Hajisaheb L. Nadaf Babu N. Motagi Sattigarahalli Lingaraju Prakashgouda V. Patil Ramesh S. Bhat 《Plant Breeding》2017,136(6):948-953
TMV 2 is a very popular peanut variety among the Indian farmers, but it is highly susceptible to fungal foliar diseases like late leaf spot (LLS) and rust. Marker‐assisted backcrossing (MABC) in TMV 2 using foliar disease‐resistant donor, GPBD 4 and the disease resistance‐linked markers (GM2009, GM2079, GM2301, GM1839 and IPAHM103) resulted in a large number of backcross populations and also straight cross populations. Foreground selection followed by field evaluation under disease epiphytotic conditions could identify a few superior genotypes. Two homozygous backcross lines TMG‐29 and TMG‐46 showed enhanced resistance to LLS and rust diseases (score of 3.00 for both) along with 71.0% and 62.7% increase in the pod yield per plot, respectively, over the check, TMV 2. These foliar disease‐resistant and productive lines can be released as commercial varieties or can be used as genetic resources in the peanut improvement. 相似文献
10.
E. Fleta‐Soriano L. Díaz E. Bonet S. Munné‐Bosch 《Journal of Agronomy and Crop Science》2017,203(4):286-294
Melatonin (N‐acetyl‐5methoxytryptamine) is an amphiphilic low‐molecular‐weight compound found in evolutionary distant living organisms, from bacteria to mammals. It can be synthesized by plants and acts as a potent antioxidant and/or a regulator of plant growth and development. Here, we investigated the role of melatonin in plant response to drought stress and recovery in maize (Zea mays L.) plants, with an emphasis on its possible photoprotective and antioxidant role and/or signalling function in relation to the stress‐related phytohormones, abscisic acid, salicylic acid and jasmonic acid. Results show a positive correlation between endogenous contents of melatonin and photoprotection, as indicated by the maximum efficiency of photosystem II photochemistry (Fv/Fm ratio), which was confirmed further by exogenous application of melatonin during recovery from drought stress. Melatonin applications during drought recovery improved the Fv/Fm ratio in maize plants exposed to a subsequent drought stress. Furthermore, endogenous contents of melatonin positively correlated with those of stress‐related phytohormones, particularly with those of salicylic acid, although exogenous application of melatonin did not alter the contents of these defence compounds. It is concluded that melatonin can exert a defensive role in maize plants exposed to drought stress, particularly improving the efficiency of photosystem II photochemistry. 相似文献