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151.
Phosphoenolpyruvate carboxylase activity in ear organs is related to protein concentration in grains of winter wheat 总被引:1,自引:0,他引:1
The relationship between phosphoenolpyruvate carboxylase (PEPC) activities in flag leaf blade and ear organs (glume and grain) and protein content of grain as well as grain weight after flowering were studied in different winter wheat (Triticum aestivum L.) genotypes. Results showed higher PEPC activity in the developing grain than in flag leaf blade and glume during grain development. For 16 of the genotypes studied, the mean PEPC activity in the developing grain or glume at 15 and 25 days after flowering was significantly and positively correlated with final protein content of grain. Enzyme activities in glume and flag leaf blade were positively correlated with final grain weight but the activity in developing grain was weakly and negatively correlated with grain weight. The overall data suggest that PEPC may be involved in protein biosynthesis during grain development, and it may have an important role in regulating carbon and nitrogen metabolism in the ear of wheat. 相似文献
152.
株高、穗位高是影响玉米耐密性的重要株型性状,明确玉米株高、穗位高的遗传基础有利于株型改良。基于NCⅡ遗传交配设计,以陕A群和陕B群选育的85个自交系组配的246份F1群体为材料,进行株型表型评价,同时结合55 951个高质量SNPs标记,对株高、穗位高以及穗位系数进行全基因组关联分析。结果表明:株高、穗位高、穗位系数的遗传力分别为77.68%、77.04%、73.78%,且三者之间存在显著正相关。同时,通过全基因组关联分析检测到7、5、4个SNP与株高、穗位高和穗位系数显著相关,解释1.47%~ 25.27%表型变异。通过候选基因功能注释,共筛选到10个候选基因,涉及植物的生长发育、生物合成、响应非生物胁迫等过程,针对3个共定位区间和热点区间锚定 plt1、 atp2、 ZC3H46、 emp21等为候选基因。可见,通过株型表型鉴定及相关基因的挖掘,可为陕A群和陕B群两个玉米群体的株型改良提供理论基础。 相似文献
153.
Brigitte Dorn Hans-Rudolf Forrer Stéphanie Schürch Susanne Vogelgsang 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(1):51-61
The Fusarium species complex of maize kernels and stem pieces as well as mycotoxin contamination of commercial grain maize hybrids for
animal feed were evaluated in Switzerland. Throughout 2 years, natural Fusarium infection varied significantly between the years and the locations and it ranged from 0.4% to 49.7% for kernels and from
24.2% to 83.8% for stem pieces. Using the agar plate method, 16 different Fusarium species were isolated from kernels and 15 from stem pieces. The Fusarium species composition, prevalence and impact differed between the north and the south and between kernel and stem piece samples.
The dominant species on kernels in the north were F. verticillioides (32.9%), F. graminearum (31.3%), F. proliferatum (7.3%) and F. crookwellense (7.1%), in the south F. verticillioides (57.1%), F. subglutinans (24.6%), F. proliferatum (14.8%) and F. graminearum (1.5%) and on stem pieces F. equiseti (36.0%), F. verticillioides (20.1%), F. graminearum (9.5%), F. crookwellense (6.2%) and F. subglutinans (6.2%). In the south, fumonisin concentration of most hybrids exceeded guidance values for animal feed. Other Fusarium species isolated were F. avenaceum, F. culmorum, F. oxysporum, F. poae, F. sambucinum, F. semitectum, F. sporotrichioides, F. solani, F. tricinctum and F. venenatum. Maize hybrids varied in their susceptibility to Fusarium infection. Because of the high diversity of Fusarium species encountered in Switzerland representing a high toxigenic potential, we propose to screen maize hybrids for resistance
against various Fusarium species and examine maize produce for several mycotoxins in order to ensure feed safety. 相似文献
154.
María M. Reynoso Sofía N. Chulze Kurt A. Zeller Adriana M. Torres John F. Leslie 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(2):207-215
Fusarium verticillioides (sexual stage Gibberella moniliformis) is a common fungal pathogen of maize worldwide that also produces fumonisin mycotoxins. Populations of this fungus can be
diverse with respect to neutral and selectable genetic markers. We used vegetative compatibility groups (VCGs) and amplified
fragment length polymorphisms (AFLPs) to evaluate the genetic structure of three F. verticillioides populations from commercial maize fields in Argentina. Based on work with similar populations from outside South America,
we expected individuals within the populations to be genetically diverse, that genotypic variation would be distributed in
a manner consistent with random mating, and that populations from different locations would be genetically indistinguishable
from one another. We analysed 62 AFLP loci for 133 fungal isolates. All three populations were genotypically diverse but genetically
similar and potentially part of a larger, randomly mating population, with significant genetic exchange occurring between
the three subpopulations. There was no evidence for linkage disequilibrium at P = 0.05. The low values of G
ST
, the lack of frequent private alleles, and the lack of a systemic pattern of linkage disequilibrium all suggest that sexual
reproduction is sufficiently common in F. verticillioides and that the dispersal of strains is sufficiently efficient for the population of F. verticillioides in the main maize growing region to be a single randomly mating population with no detectable genetic subdivision. Thus differences
in disease and/or toxin production observed in this region are best attributed to differences other than the genetic composition
of the population. 相似文献
155.
Zi Shi Ruyang Zhang Jinfeng Xing Minxiao Duan Yuandong Wang Aiguo Su Fengge Wang Liwen Xu Hongli Tian Jidong Wang Wei Song Jiuran Zhao 《Plant Breeding》2018,137(5):706-713
Ear shape substantially correlates to grain yield, so understanding their genetic architecture is of great significance in maize breeding. Ear length (EL), ear diameter (ED), length of barren tip (LBT) and cob diameter (CD) were determined for 240 doubled haploid maize lines, and all four traits showed a relatively high broad sense heritability around 77%. Using this DH population consisting of 240 lines and a genetic map constructed from 964 SNPs, a total of five, four and three QTLs were identified for EL, ED and CD, respectively, in three various growing conditions. Among these, qEL1‐1, qED1 and qCD1 were consistently mapped at an overlapping location on Chr1, which contributed 15.7, 28.3 and 22.6% of the phenotypic variation in EL, ED and CD, respectively. All other QTLs exhibited minor effect with the phenotypic variation explained ranging from 4.7% to 7.8%. Because most of the QTLs were detected in at least two different planting environments, they appear to be potential loci for gene isolation and marker development in maize molecular breeding. 相似文献
156.
不同密度下玉米倒伏相关性状与产量的研究 总被引:8,自引:1,他引:7
研究分析7.5万株/hm2和9.0万株/hm2密度下14个杂交组合茎秆穿刺强度、压折强度和穗位系数的变化与倒伏的关系,并利用逐步回归和通径分析,解析其对产量的影响作用。结果表明,茎秆穿刺强度、压折强度、穗位系数、倒伏率、密度与产量密切相关。随着密度的提高,穗位系数和倒伏率分别增加2.4%、88.51%,茎秆穿刺强度、压折强度和产量分别降低4.4%、22.26%、4.6%。过高的密度影响各性状间的相关程度发生变化,尤其是高密度下与产量密切相关的茎秆压折强度、倒伏率,其相关性表现得更显著。通过对产量作用因子进行分解,发现高密度下对产量的影响作用倒伏率穿刺强度压折强度,其作用系数分别为-0.670、0.224、0.171,最终遴选出耐密性优异的高产组合ZD181和ZD179。 相似文献
157.
158.
玉米鼠耳病(maize wallaby ear disease,MWED)是近年在我国玉米上新出现的病害,已对四川北部、重庆及贵州等地的玉米生产造成严重危害。该病在玉米上引起显著矮缩,叶变小,僵硬,叶背面形成白色、扁平的腊泪状瘿瘤等典型症状。玉米鼠耳病毒(Maize Wallaby Ear Virus,MWEV)可能与我国发生的玉米鼠耳病有关,国外报道MWEV的昆虫介体有3种:二点叶蝉(Cicadula bipunctella)、斑翅二室叶蝉(Balclutha punctata)及Nephotettix pallida,但研究表明我国发生的MWEV仅与二点叶蝉及斑翅二室叶蝉有关。更新栽培技术、改变生态条件及传播介体暴发是引起MWED流行的重要原因。本文综述了MWED的分布与危害、病原致病因子的鉴定、病害流行及防治等方面的研究进展。 相似文献
159.
160.
为探讨不同生理发育时期日本大耳白兔红细胞免疫功能的变化规律,应用红细胞C3b受体花环(E—C3bRR)和红细胞免疫复合物花环(E—ICRR)试验以及红细胞免疫粘附调节因子活性测定试验.对不同生理发育期日本大耳白兔红细胞免疫学进行了研究。结果显示:随着年龄的增长,日本大耳白兔的红细胞C3b受体花环(E—C3bRR)和红细胞免疫粘附促进因子(RFER)显著降低(P〈0.01),而红细胞免疫复合物花环(E—ICRR)和红细胞免疫粘附抑制因子(RFIR)显著升高(P〈0.01)。日本大耳白兔红细胞E—C3bRR和RFER与年龄呈显著负相关,而E—ICRR和RFIR与年龄呈显著正相关。 相似文献