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201.
温度和气体成分对冬枣果实贮藏期间品质的影响   总被引:7,自引:0,他引:7  
主要探讨冬枣(Ziziphus jujuba Mill. cv Dongzao)在-1 C的动态气调(CA-Ⅰ, 70% O2 0% CO2处理7天,然后转入5% O2 0% CO2中)、普通气调(CA-II, 5% O2 0% CO2;CA-III, 10% O2 0% CO2)及普通冷藏和常温(25C)等条件下,果实发病率、色素、可溶性固形物、可滴定酸、乙醇和乙酸乙酯含量等的变化。结果表明:与普通冷藏相比,气调贮藏能减缓果实的腐烂,抑制色素的分解和减少果肉中乙醇、乙酸乙酯的含量。动态高氧处理能有效地保持果实的颜色,抑制色素降解及果皮褐变。CA-Ⅲ (10% O2 0% CO2)能有效地减少果肉乙醇的含量而CA-Ⅱ(5% O2 0% CO2)能有效地减少果肉乙酸乙酯的含量。气调贮藏的果实可滴定酸及可溶性固形物含量与其他处理的果实没有明显的差异。  相似文献   
202.
The major components of the sex pheromone of Dioryctria abietivorella (Groté) (Lepidoptera: Pyralidae) were recently identified as (9Z,11E)‐tetradecadien‐1‐yl acetate (9Z,11E‐14:Ac) and a polyunsaturated, long‐chain hydrocarbon (3Z,6Z,9Z,12Z,15Z)‐pentacosapentaene (C25 pentaene). The optimal ratio of these components and the role of potential minor components were not fully determined in the initial short report on the pheromone's identification. We tested different ratios of the two major components loaded into grey halobutyl rubber septum dispensers, placed in sticky traps deployed in conifer breeding arboreta. The optimal ratio of the two components was 200 µg 9Z,11E‐14:Ac to 2000 µg C25 pentaene. (Z)‐9‐Tetradecen‐1‐yl acetate, which had been identified previously in female pheromone gland extracts, and five other potential minor pheromone components, were tested individually as additions to the optimized two‐component lure blend. None of the ternary blends were more attractive than the optimized two‐component blend, at the ratios tested. Two lure adjuvants, a UV stabilizer (Sumisorb 300) and the antioxidant butylated hydroxytoluene, added individually or together, did not affect the attractiveness of the optimized lure blend. The Pherotech diamond sticky trap baited with the optimized lure blend was the most effective trap design among eight types of sticky trap and a bucket style trap that were tested. Traps baited with synthetic lures were as attractive as traps baited with virgin female moths. The optimized two‐component lure blend in the Pherotech diamond trap is recommended for monitoring fir coneworm infestations. The availability of an effective synthetic pheromone opens the possibility for control tactics using mating disruption or attract‐and‐kill techniques.  相似文献   
203.
Jujube trees and yields are affected by various diseases caused by fungi, bacteria, phytoplasma and parasitic plants. Nearly 30 kinds of jujube diseases, such as rust, anthracnose, white rot, fruit rots, ascochyta spot, fruit shrink, dieback and witches’-broom, have been known so far. The purpose of this review is to compile the literature published about different aspects of the most threatening diseases occurring in jujube worldwide. Natural occurrence of diseases of minor importance is listed.  相似文献   
204.
黄土高原半干旱区不同密度山地苹果园水分生产力模拟   总被引:1,自引:0,他引:1  
张丽娜  李军  范鹏  曹裕  郭正  杨小利 《生态学杂志》2013,24(10):2878-2887
采用修订WinEPIC模型,模拟研究了陕西延安和甘肃静宁1965-2009年7种不同密度处理山地苹果园产量和深层土壤水分效应.结果表明:各密度处理4~45年生果园产量均呈现初期快速增加,达到最大值后又逐年波动性降低趋势;果园密度越高,初期产量增加越快,后期产量随降水量年际波动越剧烈.各密度处理果园遭受干旱胁迫规律基本一致,即生长前期无干旱胁迫,随种植年限延长干旱胁迫波动性加剧,生长后期干旱胁迫日数与年降水量波动趋势相反.生长初期,各密度处理果园0~15 m土层逐年土壤有效含水量均呈现波动性强烈降低趋势,延安和静宁分别在17~22年生和13~20年生之后土壤有效含水量维持在0~600 mm的较低水平.各密度处理果园0~15 m土层土壤湿度剖面分布特征相似:均经历了土壤湿度逐年降低和土壤干层逐年加厚的干燥化过程,土壤稳定干层深度可达12 m.基于0~15 m土壤有效水分含量和4~45年果园产量模拟结果确定,延安和静宁果园适宜种植密度分别为650~800和550~700 株·hm-2.
  相似文献   
205.
灌水定额对旱区苹果园土壤水盐再分布的影响   总被引:3,自引:0,他引:3  
以甘肃省秦安县盐渍化苹果园土壤为研究对象,采用大田试验的方法在苹果花期研究了不同灌水定额(0、900、1800、2700、3600 m3.hm-2)对果园0~100 cm土层水盐再分布(10、20、30 d)的影响.结果表明:随着灌水定额的增大,Na+淋溶深度增加,且再分布的滞后效应明显;Ca2+的"零通量面"逐渐消失;Mg2+的"零通量面"面宽逐渐增加;Cl-淋溶迁移方式由波动式变为直线式,蒸发迁移方式由波动式变为阶梯式;SO42-再分布方式呈点穴式;HCO3-再分布累积层位逐渐上移.在地下水位埋藏较深的土壤剖面中部存在一个"盐分零通量面",在水分再分布过程中,"盐分零通量面"的位置逐渐向下移动,体现旱地土壤水分耗竭特征.灌水定额在2700~3600 m3.hm-2时,灌溉有利于土壤剖面0~100 cm土层盐分和水溶性Na+的淋洗;灌水定额在1800 m3.hm-2以下时,灌溉加速了土壤表层盐分的累积.从钠盐淋洗和节水两方面综合考虑,旱区盐渍化果园土壤春季适宜的灌水定额为1800~2700 m3·hm-2.  相似文献   
206.
以枣(Jujube)皮为原料,经酶解和微波超声波处理后提取红色素,研究酰基化剂(Acylating agent)对红色素理化性质的影响.结果显示,枣皮红色素分别与阿魏酸和水杨酸形成的复合物对光和部分金属如Na+、Ca2+和Fe3+稳定;在pH 1~7范围内不稳定,pH 9~14范围内稳定.结果表明,阿魏酸和水杨酸与枣皮红色素复合后产生的酰基化产物有助于红色素分子的稳定.  相似文献   
207.
Agricultural activities represent a global threat to biodiversity, yet little is known about the relative importance of different agricultural land uses in relation to their wildlife communities. We explored bird community structure, diversity, and composition in a landscape dominated by primary tropical dry forest, and in three agricultural systems (i.e., tree orchards, herbaceous cropfields, cattle pastures) to evaluate the way in which birds use different habitats within the landscape. Tropical dry forests had the highest species richness and community evenness, although the bird community in tree orchards was also relatively species rich and even. Cattle pastures had more bird species than cropfields but both habitats were comparatively species poor with low evenness. Our results are related to habitat structure and the spatial location of sites within the landscape matrix. Based on our observations, we recommend including native tree species within agricultural systems and surrounding areas to provide additional resources for birds. Finally, we suggest promoting natural recruitment of native trees and shrubs within cattle pastures to provide suitable habitat for species that use tropical dry forest plants. Abstract in Spanish is available at http://www.blackwell‐synergy.com/loi/btp .  相似文献   
208.
桃园生草对桃树节肢动物群落多样性与稳定性的影响   总被引:3,自引:0,他引:3  
Jiang JX  Wan NF  Ji XY  Dan JG 《应用生态学报》2011,22(9):2303-2308
对种植白三叶草的桃园(生草桃园)和非生草桃园的桃树节肢动物群落进行分析比较.结果表明:生草桃园桃树天敌、中性类群和植食类群数量分别是非生草桃园的1.48、1.84和0.64倍,而节肢动物群落个体总数无显著差异;与非生草桃园相比,生草桃园桃树节肢动物群落丰富度(83.733±4.932)、多样性(4.966±0.110)和均匀性指数(0.795±0.014)均显著升高,而优势度指数(0.135±0.012)显著降低.稳定性指数S/N、Sd/Sp与非生草桃园均无显著差异,但Nn/Np、Nd/Np及Sn/Sp均显著高于非生草桃园.生草桃园桃树节肢动物群落多样性与稳定性指数N/Np、Sd/Sp、S/N存在显著的负相关关系,而与Nn/Np、Sn/Sp无相关性;非生草桃园多样性与稳定性指数Nn/Np、Nd/Np存在显著的正相关关系,而与其他稳定性指数无显著相关性.  相似文献   
209.
The geometric attributes and physical, mechanical, and chemical properties were determined for 11 Indian jujube (Ziziphus mauritiana Lamk.) cultivars grown in Saudi Arabia including Zaytoni, Kashmiri, Komethry, Um-Sulaem with spines, Toffahy, Um-Sulaem without spines, Abdel-Sattar, Pu-Yun, Pu-Pineau, seedy ber, and buddling ber. The geometric mean diameter, surface area, sphericity, and shape index of the fruits ranged from 20.61 to 42.48 mm, 1339.58–5666.92 mm2, 71.39–96.80%, and 110.25–275.18%, respectively. The fruit physical properties, i e fruit weight, fruit volume, stone weight, flesh weight, true fruit density, and pulp-stone ratio varied from 4.71 to 39.02 g, 4.78 to 42.75 cm3, 0.11 to 2.35 g, 4.61 to 36.67 g,0.913 to 1.055 g/cm3, and 7.90 to 43.11, respectively. In addition, the mean color value of L*, a* and b* for the fruits ranged from 64.48 to 96.33, 2.65–4.05, and 6.32–84.36, respectively. The mechanical properties, including elastic range, bioyield force, modulus of elasticity, plastic range, and rupture force ranged from 2.31 to 8.86 mm, 21.64–325.77 N, 14.15–124.09 N/s, 0.83–3.45 mm, 56.42–364.21 N, and 107.77–480.91 N/s, respectively. The greatest rupture force belonged to the Pu-Pineau cultivar and the smallest belonged to the Um-Sulaem without spines cultivar at the horizontal orientation of both cultivars. The fruit chemical analysis values for total soluble solids, titratable acidity, total soluble solids/titratable acidity ratio, and vitamin C ranged from 13.43 to 23.55%, 0.48–1.27%, 14.24–39.85%, and 55.27–164.47 mg/100 g, respectively. The relevant data obtained for the 11 varieties of Indian jujube are valuable for developing and designing machines for processing operations, transportation, separating, packing, sorting, and harvesting. Additionally, the findings revealed considerable variation in chemical content, physical and mechanical characteristics among the tested cultivars.  相似文献   
210.
枣树组织培养研究进展   总被引:3,自引:0,他引:3  
综述了枣树的器官培养、愈伤组织培养、花药培养、胚与胚乳培养、原生质体培养以及影响枣树组织培养的其他因素。营养器官培养报道的最多,其他外植体的培养相对较少,研究尚处于起步阶段。还针对枣树组织培养存在问题提出了今后的研究方向。  相似文献   
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