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排序方式: 共有173条查询结果,搜索用时 31 毫秒
1.
以黑暗培养(D)为对照,阐明了蓝光(B)连续光照对大豆(Glycine max L.Merr.)芽苗菜品种东农690生长和类黄酮合成的影响。结果表明:与对照组相比,蓝光连续光照36 h显著提高了大豆芽苗菜子叶中山奈酚(kaempferol)和黄豆苷元(daidzein)的含量,同时子叶中蓝光光受体基因CRY1、CRY2,类黄酮合成相关基因IFS的表达量也显著提高。处理组中,大豆芽苗菜下胚轴中黄豆苷(daidzin)含量逐渐增加,黄豆苷元(daidzein)、染料木素(genistein)、染料木苷(genistin)和山奈酚(kaempferol)的含量先升高后下降,但在36 h时均显著高于黑暗处理。在蓝光光照6和24 h时,大豆芽苗菜下胚轴中苯丙氨酸解氨酶(PAL)与查尔酮异构酶(CHI)活性与对照组相比均显著提高。类黄酮合成途径相关基因PAL、CHS、ANS、IFS的表达量在蓝光处理下均是先升高后下降,而蓝光光受体基因CRY1与CRY2的表达量随着光照时间延长逐渐升高。 相似文献
2.
A study was established in the Missouri Ozarks to evaluate coppice regeneration of oak. Five years after a 32-year-old stand was clearcut and regenerated naturally through stump sprouts, the dominant sprout on each stump was identified based upon height. Treated plots were thinned to the single dominant sprout on each stump whereas control plots were not thinned. Twenty-five years later the largest 247, 371, 494, and 618 stems per ha were examined and height of the dominant sprout at age 5 was found to be strongly related to dbh at age 30 in both thinned and unthinned plots. However, in the thinned plots, the largest 494 stems per ha were on average 11%, 28%, and 58% greater, respectively, in height, dbh, and volume compared to similar dominant sprouts in unthinned plots. Logistic regression analysis was used to develop curves for the evaluation of potential gains from clump thinning. In this analysis, the average height of a stand at age 5 was used to estimate thinning gains at age 30. 相似文献
3.
为筛选最适合芽菜培养的小豆品种,以‘白红8号’为试材,设置3种生长调节物质(乙酰水杨酸、乙烯利和6-苄氨基腺嘌呤(6-BA))的各6个浓度(0.0、0.1、0.2、0.3、0.4、0.5 mmol/L;0、20、30、40、50、60 mg/L和0、2、3、4、5、6 mg/L)喷施处理,测定其生物特性(上胚轴长度、上胚轴直径、萌发率、鲜重、干重和产出比)、营养成分(可溶性蛋白和可溶性糖)及抗氧化等特性。结果表明:3种生长调节物质喷施处理都能够提升其营养价值,在乙烯利喷施浓度为50 mg/L,‘白红8号’小豆芽苗菜中各营养成分、酶活性及抗氧化性等均可达到最大值,显著提高了其营养价值。因此,为提高生产中小豆芽苗菜的产量和营养价值,最终确定乙烯利喷施浓度为50 mg/L效果最佳。 相似文献
4.
T. Hodgkin 《Euphytica》1977,26(2):401-408
Summary Brussels sprouts inbred plants, homozygous for the same recessive S-allele, were intercrossed in all combinations and the number of pollen tubes penetrating the stigmas of such crosses measured. The results of five such experiments showed that pollen as well as stigma is significant in determining the number of pollen tubes counted. It was also found that the capacity of a plant's stigmas to permit pollen tube penetration was independent of the capacity of its pollen to penetrate other plants' stigmas. Variation in pollen tube production between pollens of the plants tested was often greater than that between their stigmas. 相似文献
5.
S. Louarn A. M. Torp I. B. Holme S. B. Andersen B. D. Jensen 《Genetic Resources and Crop Evolution》2007,54(8):1717-1725
Fifty-nine Brassica oleracea cultivars, belonging to five botanical varieties, were evaluated for microsatellite (SSR) polymorphisms using 11 database
sequence derived primer pairs. The cultivars represented 12 broccoli (Brassica oleracea var. italica), ten Brussels sprouts (B. o. var. gemmifera), 21 cabbage (B. o. var. capitata, including the groups white and red cabbage), six savoy cabbage (B. o. var. sabauda), and ten cauliflower (B. o. var. botrytis) cultivars from 13 seed suppliers. The 11 primer pairs amplified in total 47 fragments, and differentiated 51 of the cultivars,
whereas the remaining eight cultivars were differentiated from the rest in four inseparable pairs. All SSR markers, except
one, produced a polymorphic information content (PIC value) of 0.5 or above. The average diversity for all markers within
the tested material was 0.64. There was no major difference in the diversity within botanical varieties and groups. The cluster
analysis and the resulting dendrogram showed that the cultivars tended to group within these taxonomic units. The present
study substantiates the use of microsatellite markers as a powerful tool for cultivar differentiation and identification in
vegetable brassicas. 相似文献
6.
The purpose of this study was to investigate the effect of glucose on glucosinolates, antioxidants and metabolic enzymes in Brassica sprouts. After glucose treatment, total glucosinolates, phenolics and anthocyanin contents and antioxidant activity were significantly enhanced in Chinese kale and pak choi sprouts, while only the anthocyanin and ascorbic acid contents were increased in radish sprouts. These results indicate that glucose treatment has selectively improved the nutritional compounds in different Brassica sprouts. 相似文献
7.
[目的]筛选诱导珙桐茎愈伤组织的最佳培养基,为建立悬浮细胞系以及大规模繁殖珙桐提供前期技术基础。[方法]采集5年生以下珙桐的嫩枝条幼嫩茎为外植体,环割后接种在改良MS培养基上,培养基设25个处理,分别添加浓度为0、0.1、0.2、0.3、0.4 mg/L的NAA,浓度为0、10、20、30、40 mg/L的豆芽汁和浓度为0、5、10、15、20 mg/L的番茄汁。[结果]天然提取物和植物生长调节剂对珙桐茎诱导愈伤组织都有影响,其影响程度是NAA>豆芽汁>番茄汁。改良MS培养基添加30 mg/L豆芽汁+20 mg/L番茄汁+0.4 mg/LNAA是诱导珙桐茎愈伤组织的最佳培养基,诱导出的愈伤组织质量好,出愈率高达98%。[结论]添加天然提取物可诱导出质量好的珙桐茎愈伤组织,这与豆芽汁和番茄汁含有丰富的维生素B和维生素C有关。 相似文献
8.
模拟工厂化生产豆芽工艺培育黄豆芽,对培育过程中出现的烂芽病样进行病原菌的分离、纯化及鉴定,确定病原菌为立枯丝核菌(Rhizoctonia solani);并测定了立枯丝核菌不同菌量对绿豆芽的致病性,结果显示:不同接种量引起绿豆芽的发病时间、发病率及生物产量均存在明显差异。接种量为2块菌饼配制5 mL和2块菌饼配制10 mL的菌丝悬浮液造成严重的烂芽,第5天发病率分别达46 %和25 %。不同处理防治豆芽立枯病的试验表明:40 ℃热力消毒、1 %石灰水和1/5 000高锰酸钾均有一定的防治作用,相对防治效果分别为91.30 %、54.35 %和50.00 %。 相似文献
9.
影响杉木休眠芽数量的因素 总被引:2,自引:0,他引:2
杉木萌芽更新的繁殖基础是休眠芽,其数量对更新成败关系极大。通过对立木树干基部取样测定,基本查清影响杉木休眠芽数量变化的因素。研究结果表明,杉木休眠芽的数量随林分立地条件而变化,立地愈优良,休眠芽数量愈少,中心产区少于边缘产区;在同一林分中,大径级立木休眠芽的数量少于小径级的;随林分年龄增加休眠芽数量增加,至中龄林阶段时达最多,以后随年龄增加逐渐减少;影响杉木休眠芽数量的主导因子为林分年龄和立地条件。作者还对更新措施提出合理建议。 相似文献
10.