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991.
Sameh Boukef Bruce A. McDonald Amor Yahyaoui Salah Rezgui Patrick C. Brunner 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(1):111-122
The occurrence of fungicide resistance in Mycosphaerella graminicola populations from Tunisia was investigated by examining mutations known to be associated with strobilurin and azole resistance.
Few mutations associated with fungicide resistance were detected. No evidence for strobilurin resistance was found among 357
Tunisian isolates and only two among 80 sequenced isolates carried mutations associated with azole resistance. A network analysis
suggested that these mutations emerged independently from mutations found in previously described European populations. The
population genetic structure of M. graminicola in Tunisia was analyzed using variation at 11 microsatellite loci. Populations in Tunisia were characterized by high gene
and genotype diversity. All populations were in gametic equilibrium and mating type proportions did not deviate from the 1:1
ratio expected under random mating, consistent with regular cycles of sexual reproduction. In combination with a high degree
of gene flow among sampling sites, M. graminicola must be considered a pathogens with high evolutionary potential. Thus, control strategies against Septoria blotch in Tunisia
should be optimized to reduce the emergence and spread of resistant isolates. 相似文献
992.
Hyun Cheol Soh Ae Ran Park Sangkyu Park Kyoungwhan Back Jae Bok Yoon Hyo Guen Park Young Soon Kim 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(1):37-48
To elucidate the functional roles of PR10 genes from two pepper species during plant-pathogen interactions, PR10 genes were isolated from fungal-resistant (Capsicum baccatum var. PBC80) and fungal-susceptible (C. annuum var. Yeoju) pepper fruits infected with anthracnose fungus (Colletotrichum acutatum). Despite strong nucleotide sequence identity, there were significant differences in the patterns of gene expression and
protein accumulation between the genes from the two host species. Induced expression of the PR10 mRNA in PBC80 (bacPR10) was highly maintained from 24 h after infection (HAI) rather than that in Yeoju (annPR10). These mRNA expression patterns were correlated with the level of respective protein that was detected as two or three
bands in each species. Substantial induction of bacPR10 proteins was confirmed by 2D-gel analysis followed by immunoblotting. Immunolocalization study showed that deposition
of bacPR10 was exclusively observed in the pericarp of PBC80 fruits after fungal infection, suggesting functional significance
in defence. Additionally, in vitro analysis of the enzymatic properties of PR10 proteins revealed that recombinant bacPR10 had higher ribonucleolytic activity
and exhibited less sensitivity to proteinase treatment than did annPR10. Taken together, these results support the idea that
relative abundance and prolonged longevity of bacPR10 in PBC80 fruits may contribute to their increased resistance in response
to the anthracnose fungus, as compared with Yeoju fruit. 相似文献
993.
Zhixiang Zhang Shan Peng Dongmei Jiang Song Pan Hongqing Wang Shifang Li 《European journal of plant pathology / European Foundation for Plant Pathology》2012,132(1):9-16
This study aimed to develop a polyprobe for the simultaneous detection of four viroids that infect grapevine: Hop stunt viroid (HSVd), Australian grapevine viroid (AGVd), Grapevine yellow speckle viroid-1 and 2 (GYSVd-1, 2), using a non-isotopic dot blot hybridization technique. A polyprobe was constructed by cloning tandem
full-length sequences of HSVd, AGVd and GYSVd-1 into a single vector. The cRNA polyprobe detected all four viroids with similar
sensitivity to that obtained using individual probes. In addition, samples of 78 varieties from Beijing and Xinjiang were
analyzed using the polyprobe to survey the incidence of grapevine viroids in China. The result demonstrated that grapevine
viroids were detected in 56 (71.8%) varieties. In this study, a rapid, reliable and cost-effective approach to the simultaneous
detection of four grapevine viroids has been developed which has the potential for routine use in quarantine and certification
programs. 相似文献
994.
Biological control of postharvest diseases of fruit 总被引:1,自引:0,他引:1
Carla Alexandra Nunes 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(1):181-196
Postharvest decay in harvested fruit causes considerable economical losses. Fungicides are the primary means to control these
losses. Public concern in food safety and environmental issues and the increase of pathogen resistant populations have enhanced
the interest in developing alternative methods to fungicides to control postharvest fruit decay. During the last two decades
a huge information and advances concerning the selection of antagonists, mode of action, different approaches to enhance biocontrol
activity, formulation and production have been achieved, and some biofungicides are already in the market. It is likely that
several more products will enter the market in the near future, as the result of the biological control research programs
worldwide. Nonetheless, it is necessary to continue finding new potential microorganisms, better understanding the mode of
action, and pathogen, antagonist and host interactions, to increase the potential of biocontrol helping to become a real alternative
to synthetic postharvest fungicides. This article presents an overview of postharvest biological control approaches and explores
new research possibilities to improve biocontrol activity. 相似文献
995.
996.
Sergio Lanteri Ezio Portis Alberto Acquadro Rosario P. Mauro Giovanni Mauromicale 《Euphytica》2012,184(3):311-321
The species Cynara cardunculus includes the globe artichoke (var. scolymus), the cultivated cardoon (var. altilis) and the wild cardoon (var. sylvestris). The three taxa are sexually compatible and originate fertile F
1 progenies, which, given the high heterozygosity of the species, are highly segregating. We report the characterization of
two F
1 populations, one bred from a cross between globe artichoke and cultivated cardoon, and the other between globe artichoke
and wild cardoon. Both populations featured a wide array of phenotypes in relation to several traits, and some of the newly
developed genotypes are of interest for the ornamental market. The two populations were genotyped at 50 microsatellite (SSR)
loci: in the globe artichoke × wild cardoon and globe artichoke × cultivated cardoon progenies 116 and 97 alleles were respectively
detected. SSR pattern scores were used to produce an UPGMA dendrogram and a PCoA plot. A set of nine SSR loci, evenly dispersed
across the genome, was shown to be sufficient to unambiguously identify each segregant. The molecular fingerprinting is useful
for establishing the true to type correspondence of propagative materials in nurseries and ensures the effective correspondence
between the real and the declared identity of a clone. 相似文献
997.
Ploidy manipulations and interspecific crosses have allowed considerable genetic progress in Musa breeding, but estimation
of genetic parameters for parental selection remains a major challenge. This study aimed to determine the components of genetic
variance and the relative contribution of genetic effects to phenotypic variation of yield and phenological traits in secondary
triploid hybrids from tetraploid–diploid crosses. The hybrids were evaluated in two consecutive growth cycles on a tropical
forest site. Non-genetic effects accounted for a large fraction of the variation observed for most traits, except bunch weight.
Partitioning of genetic variance into additive and dominance components confirmed the predominant role of additive genetic
effects on the expression of bunch weight, fruit filling time, fruit length, plant height, and number of leaves while primarily
non-additive effects accounted for suckering behavior and fruit circumference. Maternal general combining ability (GCA) effects
accounted for the additive genetic variation in plant height and number of leaves, suggesting that selection for these traits
should be carried out in tetraploid clones. Conversely, paternal GCA effects were the primary causes of genetic variation
for fruit filling time, bunch weight, and fruit length, suggesting that these characters should be selected for in diploid
clones. Specific combining ability (SCA) effects were observed for all traits, except fruit filling time, suggesting that
additional genetic gain could be achieved through recombinative heterosis for these traits. 相似文献
998.
Zhenchang Liang Min Sang Benhong Wu Aihong Ma Shengjian Zhao Gan-Yuan Zhong Shaohua Li 《Euphytica》2012,186(2):343-356
Variation patterns and inheritance of anthocyanin content in the ripe berries of a tetraploid × diploid table grape cross population were investigated in two successive years. The population segregated for three different ploid levels: dipolids, triploids, and tetraploids. A total of 28 different anthocyanins were detected and quantified in the progeny population. Transgressive segregation for the total anthocyanin content was observed in all the three ploid progeny populations. The total anthocyanin content increased as the ploid level increased. The broad sense heritabilities (H2) of the total anthocyanin content were all relatively high, ranging from 0.53 to 0.98, 0.57 to 0.97 and 0.43 to 0.94 in the diploid, triploid and tetraploid population, respectively. Our results suggested that the total anthocyanin content followed an additive inheritance model in this polyploid segregation population. We also observed that the relative contribution of individual anthocyanins to the total anthocyanin content varied significantly among different ploid populations, suggesting that genetic background has important impact on the accumulation of the individual anthocyanin compounds. These results will help develop better breeding strategies in a polyploid table grape breeding program for improving the content of anthocyanins, an important class of polyphenolics possessing antioxidant activities and many other health-related benefits. 相似文献
999.
Varietal seed mixtures tend to increase and stabilize crop yields, yet their application is sparse. Large-scale cultivation of variety mixtures may require a better understanding of how inter-varietal interactions and their interaction with the environment may influence the grain yield of variety mixtures relative to their component varieties. For this purpose, six variety mixtures of spring barley and 14 component varieties were grown in each of 17 trial environments. A total of 28 observed and a priori plant characteristics, including grain yield, disease severity and weed competitiveness, were derived for each component variety in each trial. The relationship between inter-varietal diversity of each characteristic and the mixing effect on grain yield was analysed. Additionally, various types of yield stability were estimated and compared among mixtures and component varieties. One mixture out-yielded all of its component varieties in almost half of the trial environments. Inter-varietal diversity in grain yield potential correlated significantly with mixing effect, as did straw length diversity when weighted with weed pressure. The grain yields of most mixtures were more stable across environments than their component varieties when accounting also for the general response to environmental productivity. Hence, most mixtures adapted slightly better to environmental productivity and were less sensitive to environmental stress than their component varieties. We conclude that the efficacy of variety mixtures may be enhanced by mixing relatively high-yielding varieties differing in responsiveness to environmental productivity. 相似文献
1000.
S. Gandhi Doss S. P. Chakraborti S. Roychowdhuri N. K. Das K. Vijayan P. D. Ghosh 《Euphytica》2012,185(2):215-225
Sericulture is an agro-based industry, which heavily depends on mulberry (Morus spp.) for its sustainability, as mulberry leaf is the only available feed for the silkworm Bombyx mori L. Sericulture, in West Bengal and other subtropical regions in India, suffers from lack of adequate quantity of quality
mulberry leaf during the colder months, the best season for rearing the high yielding bivoltine silkworm hybrids. In order
to develop mulberry varieties, which can sustain normal growth during these colder months to yield better, efforts have been
made in different research institutes in India. The present report is part of such an effort in which accessions in germplasm
bank were screened for better growth, leaf retention and leaf yield contributing associated traits. Twenty three selected
parents were crossed, 3,500 seeds were sown, 2,700 seedlings were transplanted to progeny row trail, selected 210 hybrids
were evaluated under primary yield trial and finally nine hybrids along with a control variety were studied in detail for
all leaf yield contributing traits under final yield trial. Stability analysis was adopted to identify hybrids, which can
yield stably across seasons. The hybrids CT-44 and CT-11 out yielding the control by 17.17 and 7.11% were selected as these
hybrids yield 7.93 and 8.15 mt/ha leaf respectively during the colder months (February) for their direct use as cultivars
in West Bengal and other subtropical areas of India to sustain bivoltine sericulture to produce quality and gradable silk
fibers. 相似文献