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排序方式: 共有128条查询结果,搜索用时 15 毫秒
1.
采用不同浓度的氯化汞溶液(0.5、1.0、2.5、5.0、10.0、25.0、50.0、100.0 mg/L)对不同品种苋菜种子进行浸种处理。结果表明,Hg+对苋菜种子萌发的影响在低浓度时有促进作用,随着Hg+浓度增加,苋菜种子的根长和芽长都明显减少,当Hg+浓度达到100 mg/L时,苋菜种子见萌芽,但都有红褐色痕迹,即汞污染现象非常明显;Hg+较高浓度时,各个不同品种苋菜种子导电率相对较高,种子活力相对较低。 相似文献
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Alfredo Manicardi Laura Scarabel Josep María Llenes José María Montull María Dolores Osuna Joel Torra Farré Andrea Milani 《Pest management science》2023,79(12):4886-4896
BACKGROUND
Amaranthus palmeri is an aggressive annual weed native to the United States, which has become invasive in some European countries. Populations resistant to acetolactate synthase (ALS) inhibitors have been recorded in Spain and Italy, but the evolutionary origin of the resistance traits remains unknown. Bioassays were conducted to identify cross-resistance to ALS inhibitors and a haplotype-based genetic approach was used to elucidate the origin and distribution of resistance in both countries.RESULTS
Amaranthus palmeri populations were resistant to thifensulfuron-methyl and imazamox, and the 574-Leu mutant ALS allele was found to be the main cause of resistance among them. In two Spanish populations, 376-Glu and 197-Thr mutant ALS alleles were also found. The haplotype analyses revealed the presence of two and four distinct 574-Leu mutant haplotypes in the Italian and Spanish populations, respectively. None was common to both countries, but some mutant haplotypes were shared between geographically close populations or between populations more than 100 km apart. Wide genetic diversity was found in two very close Spanish populations.CONCLUSION
ALS-resistant A. palmeri populations were introduced to Italy and Spain from outside Europe. Populations from both countries have different evolutionary histories and originate from independent introduction events. ALS resistance then spread over short and long distances by seed dispersal. The higher number and genetic diversity among mutant haplotypes from the Spanish populations indicated recurrent invasions. The implementation of control tactics to limit seed dispersal and the establishment of A. palmeri is recommended in both countries. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献4.
籽粒苋鲜茎叶蛋白质含量及叶蛋白提取效率研究 总被引:3,自引:0,他引:3
对K112、R104等8个籽粒苋品种分不同时期进行了鲜茎叶蛋白含量分析和叶蛋白提取试验研究。结果表明,籽粒苋属于高蛋白质含量作物,全生育期叶蛋白含量平均达28.76%,采穗后茎叶平均蛋白质含量仍可达11.15%,其最佳利用时期为现蕾期至开花期,其中R104、R1011、K574蛋白质含量较高。 相似文献
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不同水氮管理对苋菜和菠菜的产量及硝酸盐含量的影响 总被引:7,自引:4,他引:7
通过田间试验研究不同水氮管理对苋菜和菠菜的产量、水分利用效率及硝酸盐含量的影响。结果表明,在同一水分处理条件下,不同的土壤供氮水平对苋菜和菠菜的产量均无显著差异,而各水分处理间也无显著差异,但水分利用效率却以W1处理(农民习惯灌水方式)为最低;苋菜和菠菜中硝酸盐含量主要受土壤的供氮量的影响,其次是土壤含水量,因此,降低土壤供氮量的同时适当降低土壤含水量,是提高水分利用效率和蔬菜品质的有效方法之一。 相似文献
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应用还原和非还原单向SDS-PAGE及二者结合的双向电泳技术,研究了红苋R104种子谷蛋白的亚基组成。谷蛋白由多种亚基组成,高分子量二硫键连接蛋白占其多数,经还原裂解成A(54KD)、B(40KD,39KD)、C(33KD,31KD)、D(22KD,20KD,18KD,)和E(15KD)5组主要单肽链单元,提出了二硫键连接蛋白的组成模式,并发现低分子量谷蛋白亚基存在肽内二硫键 相似文献
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Norain Jamalluddin Festo J Massawe 《The Journal of Horticultural Science and Biotechnology》2019,94(4):448-459
Drought is a major abiotic stress responsible for severe crop losses worldwide. Development of new crop varieties with increased drought tolerance is one way to increase crop productivity. The aim of this study was to characterise the diversity of nine accessions belonging to Amaranthus tricolor and A. cruentus, in response to drought stress using a dry-down protocol to characterise the transpiration efficiency (TE). Plants were subjected to either a gradual dry down or well-watered conditions. Results showed that TE was significantly higher (P < 0.01) in water-deficient (WD) plants compared to water-sufficient (WS) plants, 2.40 g kg?1–7.13 g kg?1 and 2.19 g kg?1–4.84 g kg?1, respectively. There was no significant difference in the fraction of transpirable soil water (FTSW) threshold decline between the amaranth genotypes. TE was highly correlated with yield under both WS (r = 0.89, P < 0.001) and WD conditions (r = 0.662, P < 0.001), and negatively correlated with root-to-shoot ratio under both WS (r = ?0.488, P < 0.05) and WD conditions (r = ?0.460, P < 0.05). Significant genotypic differences were seen for growth rate and stress susceptibility index (SSI). The result obtained in this investigation underline the need to identify genotypic variation in water use efficiency in amaranth.Abbreviations: FTSW: Fraction of transpirable soil water; NTR: normalised transpiration rate; SSI: Stress susceptibility index; TE: transpiration efficiency; WHC: water holding capacity; WD: water-deficient; WS: water-sufficient. 相似文献
8.
针对田间苋菜识别存在准确率低、样本数量少等问题,通过引入扩展感受野和提取上下文信息的ASPP注意力机制改进YOLO v5苋菜识别模型,在低数据集下改进后的模型能够显著提高F1值和mAP。实验结果表明,在低数据集下引入ASPP注意力机制后苋菜识别模型F1值提高13个百分点、mAP提高18.6个百分点。采用横向录制的方式苋菜被检测到的概率提高15.4个百分点。因此,本研究为苋菜或其他杂草在低数据集下的识别提供了有效的方法,为农业领域的杂草识别和管理研究提供了参考。 相似文献
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千穗谷(A maranthus hypochondriacusL.)是优质耐瘠薄牧草资源.为了探讨其种子的耐盐能力,分5个盐分胁迫处理:0、1、2、5、10 g/kg,分别在石英砂基质、海兴盐碱土基质和安国潮褐土基质上,进行发芽试验.结果表明,不同基质上千穗谷发芽率与盐分浓度表现出显著的负相关关系.在石英砂、海兴盐碱土、安国潮褐土基质上,千穗谷与盐分浓度的回归方程斜率分别为-5.77、-8.787、-7.95.千穗谷种子萌发盐分胁迫临界值为海兴盐碱土大于安国潮褐土,分别为3.5、3.4 g/kg;盐分胁迫极限值为安国潮褐土大于海兴盐碱土,分别为8.4、8.1 g/kg.盐分对千穗谷种子萌发及幼苗生长有一定的抑制作用;随着盐分浓度的提高,3种基质上千穗谷种子发芽率均呈下降趋势,幼苗生长状况也呈现同一趋势. 相似文献
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