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1.
向日葵[IIelianlhus anuus (L.)]是我国的重要经济作物。其花粉通常呈深浅程度不同的黄颜色。据我们掌握和查新资料,目前世界上尚未见有关白花粉方面的报道。1989年7月下旬至8月上旬,我们在吉林农业大学向日葵育种试验田的恢复系C8711群体中,先后发现4株白花粉突变体。暂分别定名为C8711—1、C8711—2、C8711—3和C8711—4。在进行人工套袋之前,此4株突变体已经在一定程度上发生了开放授粉,其中C8711—4开放授粉程度较轻。成熟时单独收获这4株突变体的种子,以进行有关遗传学研究,本文拟对白花粉突变的遗传学机理进行初步的探讨。  相似文献   
2.
J. Domínguez 《Plant Breeding》1996,115(3):203-204
The inheritance of resistance to a highly virulent population of sunflower broomrape (Orobanche cernua) has been studied in R-41, a Spanish sunflower restorer inbred line. Using the cytoplasmic male-sterile inbred line HA-89 (cms; very susceptible to this population of broomrape) as a female parent, progenies of the cross with R-41, i.e. Fl, F2 and BC1 to both parents, as well as the parental lines, were analysed for their reaction to the broomrape population EC-94. The goodness of fit of the observed vs expected segregation ratios indicated that the inheritance of resistance to broomrape in line R-41 is conferred by two independent dominant genes.  相似文献   
3.
Sequence parts of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA were analysed to screen for the intraspecific variability of a non-coding genomic region in 15 Plasmopara halstedii populations of different pathotype and geographic origin. Samples revealed uniformity in a ca. 790 Bp fragment comprising of the ITS-1, 5.8S and front parts of the ITS-2. In contrast, clear differences were found in a ca. 810 Bp fragment of the ITS-2 thus allowing differentiation between populations of pathotype 100, 310 and 330 and a group of populations representing pathotypes 700, 701, 703, 710 and 730. Samples of pathotypes 700 to730 originated from Slovakia, France, and Germany, but were uniform in both ITS sequence parts, thus indicating very recent origin of these highly aggressive physiological races. The potential use of ITS sequences for pathotype differentiation and phylogenetic studies in P. halstedii is discussed.  相似文献   
4.
Ecophysiological simulation models provide a quantitative method to predict the effects of management practices, plant characteristics and environmental factors on crop and weed growth and competition. The INTERCOM interplant competition model was parameterised, calibrated by monoculture data for three cowpea (Vigna unguiculata) genotypes that differed in growth habit, common sunflower (Helianthus annuus) and common purslane (Portulaca oleracea), and used to simulate competition of cowpea cover crops with sunflower or purslane. The simulation results were compared with observations from field competition experiments in 2003 and 2004. INTERCOM more accurately simulated actual field data for the competition of cowpea genotypes and sunflower than companion field experiments for the competition of cowpea and purslane. The validated simulation model of cowpea and sunflower at two densities was used to study the effects of cowpea growth habit on final biomass production of cowpea and sunflower. The model suggested that erect growth habit was more competitive than semi‐erect and prostrate growth habit, when cowpea genotypes were grown with sunflower. Cowpea leaf area distribution was important to higher cowpea biomass production, while cowpea height growth was important to reduce sunflower biomass. Our simulation approach is suggested as a method for crop breeders to gauge the likely success of selection for competitive crops before undertaking expensive long‐term breeding experiments.  相似文献   
5.
Resistance to the dicotyledenous parasite Orobanche cumana in sunflower is characterized by a low number of parasitic attachments and a confinement of the parasite in host tissues leading to its necrosis. To help understand what determines such resistance mechanisms, molecular, biochemical and histological approaches were employed before (early response) and after (late response) attachment of the broomrape parasite to susceptible (2603) and resistant (LR1) sunflower genotypes. The expression patterns of 11 defence-related genes known to be involved in different metabolic pathways (phenylpropanoids, jasmonate, ethylene) and/or in resistance mechanisms against microorganisms were investigated. RT-PCR and cDNA blot experiments revealed that the resistant genotype exhibited a stronger overall defence response against O. cumana than the susceptible one, involving marker genes of the jasmonate (JA) and salicylic acid (SA) pathways. Among them, the SA-responsive gene, def. (defensin), appeared to be characteristic of LR1 sunflower resistance. However, no JA accumulation and similar SA contents (250–300 ng g−1 FW) were measured by GC/MS in both genotypes, parasitized or not. In addition, three cDNAs, isolated by a suppression-subtractive hybridization, were shown to be strongly induced only in the resistant genotype 8 days post-inoculation, when the first O. cumana attachments occurred. These genes, putatively encoding a methionine synthase, a glutathione S-transferase and a quinone oxidoreductase, might be involved in detoxification of reactive oxygen species, suggesting the occurrence of an oxidative burst during the incompatible interaction. Finally, host cell-wall modifications leading to parasite-confinement were correlated with more intense callose depositions in the resistant genotype, concomitant with over-expression of the callose synthase cDNA HaGSL1 .  相似文献   
6.
《Plant Production Science》2013,16(3):204-208
Abstract

Argentina is a major sunflower producer in the world, with crop acreage of 2?2.7 million ha in the last four years. Sunflower crop yield is often influenced by sanitary constraints, mainly fungal pathogens. Helianthus petiolaris is a wild species native to North America established in central Argentina displays a high tolerance to a number of fungal diseases and insects. Controlled crosses of this species with sunflower demonstrated that H. petiolaris constitutes a valuable genetic variability source for sunflower breeding to improve tolerance to rust (Puccinia helianthi), white rust (Albugo tragopogonis), verticillium wilt (Verticillium dahliae), powdery mildew (Erisiphe sp.) and the sunflower moth (Rachiplusia nu). This places H. petiolaris in an outstanding position as a genetic resource since different important traits could be transferred to the crop through interspecific hybridization.  相似文献   
7.
探究不同磷肥施用量对菊芋块茎产量、品质、植株理化特性及磷肥利用率的影响,为实现菊芋高产优质栽培和农田磷素高效利用与科学施磷提供参考依据。于2019-2020连续两年分别于河南省原阳县和方城县布置磷肥用量田间试验,2019年设0、60、120、180和240 kg P2O5·hm-2 5个磷肥用量水平,2020年则分别设0、45、90、135、180和225 kg P2O5·hm-2 6个施磷水平。研究磷肥施用对成熟期菊芋块茎产量、品质(菊糖、还原糖含量)以及营养生长和生殖生长期地上部植株磷素积累量、叶片绿原酸、SPAD值、可溶性糖、可溶性蛋白含量等理化指标的影响,计算分析菊芋收获指数、磷肥利用率和农学效率等肥料吸收利用状况。结果表明:磷肥供应均显著提高2019和2020年菊芋块茎产量,肥料效应呈“线性+平台”趋势变化,适宜施磷量分别为155和107 kg·hm-2。此外,磷肥供应显著提高菊芋块茎菊糖和还原糖含量。与不施磷相比,2019-2020年度块茎总糖含量增幅分别平均为11.6%和18.3%。各生育期菊芋地上部植株磷素积累量、叶片绿原酸含量、SPAD值、可溶性糖和可溶性蛋白含量均随施磷量增加而明显提高。菊芋磷素收获指数(PHI)、磷肥利用率(AUP)和农学效率(AEP)均随着磷肥用量增加而明显下降,施磷处理两年平均PHI、AUP和AEP分别为0.813、15.1%和23.9 kg·kg-1。因此,合理施磷可显著提高菊芋成熟期块茎产量、改善品质,增强各生育期生理活性。在本试验条件下菊芋适宜施磷量为105~150 kg·hm-2。  相似文献   
8.
羟基肉桂酰辅酶A:莽草酸/奎宁酸羟基肉桂酰转移酶(HCT)是木质素合成过程中的关键酶之一。本研究构建了菊芋HtHCT基因的植物表达载体pCAMBIA1390-HtHCT,分别对拟南芥和本氏烟进行遗传转化,并对转基因植株进行生理生化指标测定。PCR和RT-PCR结果表明,HtHCT基因已经插入到受体植物基因组中,并能进行转录;转基因植株生理生化指标检测表明,HtHCT基因能够调节拟南芥和本氏烟中木质素的含量及组成,并对受体材料的类黄酮合成亦有一定的影响。  相似文献   
9.
观赏植物的精准应用有助于提升城市公园品质。对湛江地区14个观赏向日葵Helianthus annuus品种进行夏季田间引种试验,观测、记录和分析其8个物候特征和14个表型性状,结果表明各观赏向日葵品种间物候特征具有差异性,表型变异较为丰富,14个品种聚类为四大类群。进一步探讨了观赏向日葵应用的品种选择、种植调节及配植方式,为观赏向日葵多重配植方式、应用分类和节庆精准应用提供了科学依据。  相似文献   
10.
向日葵品种抗向日葵螟鉴定及抗性评价方法   总被引:1,自引:0,他引:1  
利用田间自然抗虫鉴定法连续3年在内蒙古巴彦淖尔市对56个向日葵品种进行了抗向日葵螟鉴定,结果表明,17个油葵品种中除P50表现为中抗(籽粒被害率为6.7%),其余品种全部表现为高抗,籽粒被害率均在0~2.5%;而39个食葵品种中仅新食葵7号表现为高抗(籽粒被害率为1.9%),其余多表现为感虫或高感,籽粒被害率在5.8%~54.1%。进一步利用黑色素鉴定法对所有品种进行了室内检测,其结果与田间抗虫鉴定结果基本吻合。由此认为:在进行田间自然抗虫鉴定时,宜根据田间向日葵螟成虫种群动态选择适宜的播期,使向日葵的开花期与向日葵螟成虫发生盛期尽量吻合,以提高害虫对向日葵的选择压力和鉴定结果的科学性,同时避免出现播期避害现象,干扰鉴定结果的准确性。  相似文献   
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