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91.
92.
Recent results on hot water as an alternative treatment open a new perspective in disease incidence reduction. In the present work peach fruit were wounded, inoculated with conidia of Monilinia laxa and 15 min, 3, 6, 12, 24 and 48 h after inoculation treated by dipping in hot water (HT) at 60 °C for 20 s. The effect of heat treatment on some cell wall genes involved in ripening such as β-galactosidase (β-GAL), pectin lyase (PL), polygalacturonase (PG) and pectin methyl esterase (PME), was analyzed by qRT-PCR. The expression levels of defense related genes, phenylalanine ammonia lyase (PAL) and chitinase (CHI), heat stress-related genes such as heat shock proteins 70 and 90 (HSP70, HSP90), and reactive oxygen species (ROS) scavenging genes were also evaluated by qRT-PCR. A 100% disease incidence reduction, as compared to untreated fruit, was obtained by treating 6 and 12 h after inoculation. Moreover, brown rot was inhibited by 85.7% when fruit were heat-treated 48 h after inoculation. The expression levels of cell wall genes (β-GAL, PL, PG and PME) showed a general decrease in HT fruit as compared to the control, whereas PAL, CHI, HSP70 and ROS-scavenging genes increased their expression level in HT samples with respect to the untreated ones. Our results show a curative activity of heat on peach inoculated with M. laxa 48 h before treatment. Each analyzed gene proved to be differentially expressed following heat treatment. 相似文献
93.
94.
95.
96.
Abscission or retention of ripening fruit is a major component of seed dispersal strategies and also has important implications
for horticultural production. Abscission-related traits have generally not been targeted in breeding efforts, and their genetic
bases remain mostly unknown. We evaluated 144 Malus accessions representing wild species, domestic cultivars, and hybrids for abscission-related traits. We found that seasonal
timing of fruit abscission in wild species and hybrids showed a broad distribution similar to that seen for domestic cultivars,
and that internal ethylene concentration at the time of abscission varied by over three orders of magnitude. Wild species,
domestic cultivars, and hybrids all included representatives that showed abscission of fruit prior to substantial production
of ethylene, as well as accessions that retained fruit for a significant period of time following ethylene production. For
all accessions that retained fruit, fruit removal resulted in abscission of the pedicel, and exogenous ethylene promoted abscission,
suggesting that the abscission zone was functional. Our results suggest important roles for mechanisms independent of fruit
ethylene production in abscission. 相似文献
97.
Harry S. Paris 《Euphytica》2003,129(1):119-126
Longitudinal striping of the fruit exterioris a common trait in Cucurbita pepo(pumpkin, squash, gourd). Striping occursas ten pairs of alternating dark and lightstripes that are regularly situated inaccordance with the ten sub-epidermalcarpellary vein tracts. Usually, the darkstripes occur in the central areas betweenthe vein tracts, with the light stripesoccupying the remainder of the fruitsurface. A new phenotype is described inwhich dark spots or streaks occur in thecentral areas between the vein tracts;these are usually accompanied by darkstreaks or stripes that occur adjacent toand over part or all of the length of someor all of the ten carpellary vein tracts. The inheritance of this irregular stripingpattern was studied by crossing anaccession that bred true for this phenotypewith a near-isogenic line havinglight-colored fruits. The resultsindicated that irregular striping isdominant to light coloration and isconferred by a single gene. Testcrossesfor allelism with regular striping wereprepared by crossing the irregularlystriped accession with near-isogenic lineshaving broad stripes, l-1
BSt/l-1
BSt, and narrowstripes, l-1
St/l-1
St. The testcross results revealed thatirregular striping is conferred by anallele at the l-1 locus, designatedl-1
iSt. The l-1
iStallele is dominant to light-colored (l-1), recessive to dark-colored (L-1), and can be co-dominant or recessiveto broad-striped (l-1
BSt) andnarrow-striped (l-1
St),depending on whether or not it is fullyexpressed. Dominance relationships at thel-1 locus can, therefore, berepresented as L-1 > (l-1
BSt > l-1
St) l-1
iSt > l-1. 相似文献
98.
99.
鲜枣脯真空渗糖技术影响因素的研究 总被引:1,自引:0,他引:1
通过对枣脯的真空渗糖技术及其影响因素进行系统的研究,结果表明:当真空度控制在0.080MPa,维持真空时间为30分钟、充气时间为60分钟;加糖采用喷糖方式、糖液的温度为95摄氏度时,为枣脯真空渗糖的最佳条件。 相似文献
100.
A quick methodology to identify sexual seedlings in citrus breeding programs using SSR markers 总被引:8,自引:0,他引:8
In citrus breeding and genetics, it is very important to distinguish between zygotic and nucellar seedlings in order to eliminate
unwanted genotypes. Usually, isozyme marker shave been employed to determine the genetic origin of young plants. In this work
we propose the use of SSR markers as an alternative methodology and compare them with isozymes in this kind of screenings.
Two different populations were analysed: one derives from an interspecific cross and the other from selfing. We conclude that,
in most cases, microsatellites are more efficient than isozymic markers to identify the sexual origin of citrus seedlings,
given their higher level of polymorphism and the scarce number of polymorphic isozymes in some populations. We describe a
quick and efficient methodology for SSR analysis, including a fast DNA extraction in microcentrifuge tubes, and visualization
through silver staining, which eliminates the need for a labelling step.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献