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71.
黑莓对水分、盐分和低温逆境的适应性   总被引:2,自引:2,他引:0  
在南京盆栽条件下,黑莓(Rubus L.spp.)“Hull”品种1年生扦插苗在土壤相对含水量为70%以上时,地上部分和地下部分均生长良好,正常开花结实;土壤相对含水量下降到50%-60%时,地上部分生长明显减弱,地下部分生长受到一定影响,但植株都能存活;土壤相对含水量下降到45%-50%时,地上部分及地下部分均生长不良,部分植株死亡;土壤相对含水量降到30%-35%时,植株无法生存。黑莓“Hull”品种扦插苗是对盐(NaCl)敏感的植物,中度(0.2%)以上盐浓度对生长有明显的抑制作用,相对于地上部分和根系,根颈部所受的影响较小,表现为地上部无新的枝条萌出,无叶片产生;地下部无新根产生;根颈部萌芽数量减少,长度变小,随着盐浓度的增加,生长减慢甚至死亡。轻度(0.1%)盐处理未见有抑制作用。黑莓不同品种的枝条抗冻性不同,所测定的3个品种中,“HuLL”抗冻性最差,LT50为-25.5℃,“Chester”与“Navoho”的抗冻性相近,LT50均为-29℃。  相似文献   
72.
木莓果实红色素的理化性质及其稳定性   总被引:11,自引:2,他引:9  
对木莓(Rubus swinhoei Hance)果实中提取的红色素理化性质进行了探讨,并就光、温度、pH值、氧化还原介质、7种金属离子、葡萄糖、蔗糖和苯甲酸钠等对其稳定性的影响进行了研究。结果表明,木莓鲜果中总花色苷含量高,属水溶性性花色苷类。该色素对热的耐受性较好,但耐氧化还原性和耐Vc较差;7种金属离子中Na^ 、Mg^2 、Al^3 和较高浓度Mn^2 (≥5.0mmol/L)对该色素的稳定性较好,并有不同程度的护色效果,Zn^2 对其稳定性较好,而Fe^3 和Cu^2 对共稳定性有明显的影响或破坏作用;葡萄糖、蔗糖和苯甲酸钠无不良影响。  相似文献   
73.
寒莓中三萜成分的研究   总被引:1,自引:0,他引:1  
从蔷薇科悬钩子属植物寒莓(Rubus buergeri Miq.)中分离鉴定了12个三萜类化合物。其中1个为新化合物,命名为寒莓酸甲酸(12a),其结构经波谱分析鉴定为2α,3α,19α,24-四羟基齐墩果-12-烯-28-酸甲酯。  相似文献   
74.
糖基化是植物次生代谢产物生物合成中重要的修饰反应。目前已报道的以二萜为底物的UDP-糖基转移酶(UGT)数量稀少。本研究基于甜叶悬钩子叶片的转录组数据,利用生物信息学分析手段,选定可能具有二萜类催化活性的UDP-糖基转移酶基因进行克隆。最终克隆得到18条UGT基因序列,在大肠杆菌中进行了异源表达,并对克隆的基因进行了初步的序列分析。本研究为进一步挖掘和验证甜叶悬钩子中UGT的功能奠定了基础。  相似文献   
75.
悬钩子属植物化学成分及药理活性研究进展   总被引:1,自引:0,他引:1  
本文对近10年来悬钩子属植物的化学成分和药理活性研究进行了综述,为该属植物的进一步开发利用提供参考。悬钩子属植物的化学成分主要包括黄酮、萜、鞣质、甾等。药理活性主要包括抗菌、抗炎、抗肿瘤、抗氧化、抗过敏、保肝、镇痛等。  相似文献   
76.
几种野生悬钩子家化的生物学基础研究   总被引:4,自引:0,他引:4  
在对中国7个省区悬钩子属(Rubus L.)资源调查的基础上,选出蓬(R.hirsutus Thunb.)、掌叶覆盆子(R.chingii Hu)、山莓(R.corchorifolius L.)和高粱泡(R.lambertianus Ser.)4个野生种进行栽培化研究。本文报道4个种的生长结果习性、物候期、营养需要、花芽分化过程以及繁殖习性,并提出了一系列栽培措施。  相似文献   
77.
植物激素对空心泡叶片不定芽形成的影响   总被引:2,自引:0,他引:2  
空心泡是蔷薇科悬钩子属植物,属小果类果树,其聚合果肉质多浆,芳香,果味酸甜。空心泡目前尚处于野生状态,是一种很有利用前景的植物。有关悬钩子属植物组织培养已有许多报道,所有这些工作都  相似文献   
78.
Bud break in protected Northern European raspberry crops is often poor and uneven with many of the sub-apical buds remaining in a dormant state. In order to improve bud break and therefore yields, the mechanism controlling bud dormancy must be determined. Canes of the biennial cultivar ‘Glen Moy’ were forced as isolated single nodes, trisections, or as intact canes after different lengths of cold storage chill unit (CU) accumulation in order to determine whether the buds were in an endodormant or paradormant state. The results showed that buds on the lower parts of the intact canes remained in a dormant state long after buds from higher up the intact cane and also the single nodes from all parts of the cane had emerged from the deepest phase of endodormancy. This would imply that these buds were being held in a paradormant state until large amounts of chilling units (>1000 CU) had been accumulated. The trisected cane portions revealed almost no significant differences in bud break levels throughout the experiment when compared with the single nodes. This suggests that removal of the apical part of the cane would be effective in improving bud break by reducing the paradormant condition. A period of secondary dormancy was also observed in the intact canes which may also exacerbate the poor bud break observed in protected crops. This was not seen in the single nodes or the trisected canes which indicates that treatments which reduce paradormancy may also minimise the risk of secondary dormancy. By identifying the phase of bud dormancy which causes poor bud break, attention can now be focused on methods which overcome paradormancy in protected crops. Such methods might include tipping (removal of the cane apex), horizontal training methods, more efficient chilling methods, and chemical treatments.  相似文献   
79.
Abstract The ecological distribution and life history characteristics of three Rubus species, i.e., R. palmatus Thunb. var. coptophyllus (A. Gray) O. Kuntze, R. microphyllus L.f. and R. crataegifolius Bunge were investigated, with particular emphasis on the seasonal growth cycles, modes of the alternation of aerial organs, and patterns of dry matter allocation, and these features were critically compared with one another. It was found that seasonal changes of aboveground biomass are strongly related to the modes of cane alternation, to underground branching producing stolons, and to their dry matter allocation patterns. The modes of cane alternation, underground branching and dry matter allocation patterns were very similar in R. microphyllus and R. crataegifolius , taking about five months from May to September. But R. palmatus var. coptophyllus showed much more gradual replacement of aerial organs, extending over seven months from May to December. These three Rubus species are often predominant in the early successional stages of pioneer communities which develop after cutting of forests in central Japan, and differentiations of the above-mentioned life history traits found in Rubus species seem to be related to the constraints inherent in their somewhat labile, changing environments, e.g., at the forest margin or clearings produced temporarily.  相似文献   
80.
 This paper reports genomic in situ hybridization (GISH) and fluorescent in situ hybridization (FISH) data for chromosomes of raspberry (Rubus idaeus 2n=2x=14), blackberry (Rubus aggregate, subgenus Eubatus. 2n=2–12x=14–84) and their allopolyploid derivatives used in fruit breeding programmes. GISH was used to discriminate labelled chromosomes of raspberry origin from those of blackberry origin in allopolyploid hybrid plants. The raspberry chromosomes were labelled by GISH at their centromeres, and 1 chromosome was also labelled over the short arm. In one allopentaploid plant a chromosome carried a terminal signal. Karyotype analysis indicated that this is a blackberry chromosome carrying a raspberry translocation. GISH analysis of an aneuoctaploid blackberry cv ‘Aurora’ (2n=8x=58) showed that both whole and translocated raspberry chromosomes were present. The basic Rubus genome has one ribosomal DNA (rDNA) locus, and in all but one case all levels of ploidy had the expected multiples of rDNA loci. Interestingly, in the blackberry cv ‘Aurora’, there were only six sites, two less than might be predicted from its aneuoctaploid chromosome number. Our results highlight the potential of GISH and FISH for genomic designation, physical mapping and introgression studies in Rosaceous fruit crops. Received: 20 February 1998 / Accepted: 12 May 1998  相似文献   
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