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1.
以盆栽的试验方式,研究了在老龄苹果园土壤中添加不同量(0、0.1、0.3、0.5 g ? kg-1)的硫磺对土壤微生物环境及再植平邑甜茶(Malus hupehensis Rehd.)幼苗的影响,为减轻苹果连作障碍提供理论依据。温室和露地盆栽结果显示:硫磺对改善连作土壤环境及促进平邑甜茶幼苗的生长具有良好的效果,但不同添加量促进效果不尽相同,其中以0.3 g ? kg-1的促进效果最为显著。与对照相比,0.3 g ? kg-1的硫磺处理浓度下平邑甜茶幼苗株高、地径、鲜质量、干质量分别增加了60.83%(26.03%,露地数据,下同)、26.78%(19.66%)、73.44%(62.15%)和93.32%(72.93%);根长、根表面积、根体积、根尖数、根系呼吸速率提高了1.47倍(1.82倍)、2.28倍(2.05倍)、2.05倍(2.74倍)、1.73倍(1.67倍)、2.12倍(1.98倍)。硫磺处理后叶片叶绿素含量、光合参数、土壤酶的活性均有不同程度提高。0.3 g ? kg-1硫磺处理具有最高的细菌与真菌比值、真菌的丰富度和多样性指数及最低的优势度指数。主成分分析发现,随硫磺添加量增加,土壤真菌群落与对照距离越来越远,但当添加量由0.3 g ? kg-1增加至0.5 g ? kg-1对改善连作土壤环境的效果不是特别明显。实时荧光定量结果表明,硫磺的添加可以显著降低串珠镰孢菌基因拷贝数。综上,0.3 g ? kg-1硫磺处理可较好地优化土壤环境,促进平邑甜茶幼苗的生长,可作为一种减轻苹果连作障碍的有效方法。  相似文献   
2.
银杏为我国传统的名贵树种,其生长缓慢、结实晚,一般要20多a才能开花结实,并且产量低。阐述银杏的生物学特征、繁殖方式、栽培管理方法、修剪整形及病虫害防治等实用技术,旨在为扩大银杏园林生产、提高银杏的种植质量和产量提供有益的参考。  相似文献   
3.
[Objective] The effect of concentrated biogas slurry on growth and physiological characteristics of cotton seedlings was studied in this experiment, and theoretical basis for the rational application of concentrated biogas slurry was provided. [Method] Potted cotton seedlings was sprayed by five different dosages of concentrated biogas slurry, the impact of different spraying quantity (163 mL·hm-2, 326 mL·hm-2, 489 mL·hm-2, 668 mL·hm-2, 815 mL·hm-2) after spraying time (after spraying 2nd day, 4th day, 6th day) on cotton seedlings growth and physiological indexes were studied. [Results] The results showed that the suitable quantity of spraying of concentrated biogas slurry had promoting effect to the cotton growth and development, the excess concentrated biogas slurry could inhibit the growth of cotton seedlings. The plant height, dry weight per plant and leaf area of spraying 489 mL·hm-2 processing are the highest, the average of two batches on the 6th day after spraying are 21.15%, 35.95%, 18.84% higher than CK, respectively. Spraying concentrated biogas slurry can improve cotton seedlings chlorophyll content, soluble sugar contents, soluble protein content. Spraying 489 mL·hm-2 processing is the highest in both batches, the average of two batches is 18.84%, 24.03%, 3.16% higher than CK, respectively. The result of concentrated biogas slurry onseedlings leaves took effect quickly, especially in 0~4th days. [Conclusion] It is concluded that the suitable amount of concentrated biogas slurry has a positive effect on the growth and physiological characteristics of cotton seedlings, which is beneficial to the formation of strong seedlings of cotton and provides the basis for the later growth of cotton.  相似文献   
4.
肉鸡安全生产质量监控可追溯系统的实现   总被引:10,自引:2,他引:8  
结合肉鸡生产日常管理,运用现代网络信息技术,对鸡肉产品生产过程诸环节中影响终端食品安全关键因素进行分析。采用基于产品批次记录与逐级编码方式,将肉鸡生产、产品加工、物流销售等与鸡肉产品安全有关的信息串连起来,建立电子文档记录,构建肉鸡安全生产质量监控可追溯系统,通过该系统消费者可逆向追溯肉鸡饲养管理信息、疾病防治与免疫情况等多项可追溯内容,达到监控肉禽食品安全目的。该系统已在山东民和集团实现。  相似文献   
5.
通过4种叶面肥在牛蒡上的应用试验,结果证明,天达-2116植物生长营养液对牛蒡增产效果显著,改善了牛蒡的品质,提高了牛蒡对白粉病的抗性,为山东省制定出口牛蒡良好农业操作规范(GAP)提供科学依据.为提高农产品出口量、增加效益提供参考.  相似文献   
6.
NaCl胁迫下栽培型番茄Na+、K+吸收、分配和转运特性   总被引:6,自引:2,他引:6  
【目的】明确盐分胁迫下栽培型番茄离子吸收、分配和转运特性。【方法】以栽培番茄为试材,以NaCl溶液为盐分胁迫条件,通过苗期耐盐性鉴定,采用原子吸收光谱法测定不同耐盐性番茄品种体内离子含量,对盐分胁迫下番茄体内离子积累、分布和转运机制进行系统分析。【结果】番茄对Na+的吸收随盐分处理浓度和时间的增加而增加,在各器官的积累量顺序为根>茎>叶。对于较耐盐品种,Na+在体内的积累总量低于盐敏感品种。盐分胁迫后,番茄叶片、茎和根系中Na+/K+比均随NaCl浓度的升高而升高。耐盐品种的Na+/K+比低于盐敏感品种。离子在体内的区域化分布情况是,较耐盐品种的Na+在根茎中的分配比例较高,盐敏感品种趋向于向叶片分配。K+在较耐盐品种的分布集中于叶片。在盐胁迫初期,盐分处理浓度超过200 mmol•L-1时,番茄植株对K+向地上部的选择运输性随着胁迫时间的延长呈现出下降的趋势。低于200 mmol•L-1时,表现出很好的选择运输性,耐盐品种的Sk/Na(运输)高于盐敏感品种,根系表现出更强的向地上部运输K+的能力。【结论】盐分胁迫下,叶片中较低的Na+含量和更强的向地上部运输K+的能力是番茄耐盐性的重要特征。  相似文献   
7.
蔬菜的质量和安全日益受到人们的关注,无公害蔬菜已成为蔬菜生产的发展方向。本文简述了无公害蔬菜的概念,分析了烟台市无公害蔬菜的生产现状及存在问题,提出了无公害蔬菜生产的措施与对策,以期为烟台市无公害蔬菜的生产提供参考。  相似文献   
8.
不同施肥模式对甘薯生长发育及高产生理特性的影响   总被引:5,自引:0,他引:5  
分层施肥是在配方施肥的基础上根据甘薯不同生育期的需肥特点进行养分供给,其增产效果好于配方施肥和普通施肥,高产机理在于通过增加光合面积、提高净同化率、改善光合产物分配来提高经济产量。  相似文献   
9.
关于推进水产养殖用药科学化管理的探讨   总被引:1,自引:1,他引:0  
我国渔药市场存在着营销秩序混乱、药品质量良莠不齐、水产养殖滥用药等问题。应从完善制度、加强管理、改进技术、提高素质几个方面入手,对渔药的生产、经营、使用每个环节实行全程质量监控,保证水产养殖用药质量。  相似文献   
10.
A two-year trial was conducted to test the interactive effects of special-for-apple organic fertilizer, CaSO4, and amino acid Ca on Fuji/Balenghaitang (Malus robusta Rehd.) rootstock in Burozem soil in China. Total Ca, exchangeable Ca, and fruit Ca were significantly improved by the soil application of CaSO4 with the highest exchangeable Ca and fruit Ca observed in Fuji apple trees treated at the rate of 3.5 kg CaSO4 per tree. 3.5 kg CaSO4 was divided into two applications, with first application in the first month after full bloom, and the second in the second month after full bloom in summer, progressively to improve fruit Ca concentration. Dividing CaSO4 into two applications in combination with organic fertilizer or amino acid Ca spray, proved to be more effective on improving the fruit Ca concentration, with the highest level of 179.17 mg/kg FW in Fuji apple trees treated with 2 kg CaSO4 applied and amino acid Ca sprayed in the first month after full bloom, 1.5 kg CaSO4 applied in summer, organic fertilizer applied in winter. Organic fertilizer applied in winter alone remarkably improved the fruit Ca concentration, as well as storage Ca in roots and stems, and the best effect was observed in Fuji apple trees which were supplemented organic fertilizer (10 kg) in winter and CaSO4 (1 kg) in the first month after full bloom per tree. The effect on Ca increment became less pronounced when the amount of organic fertilizer reached 15 kg or CaSO4 was more than 3.5 kg per tree. There was a positive correlation between the Ca/Mg ratio in soil and fruit, exchangeable Ca, and fruit Ca concentration, while a negative correlation was observed between the N/Ca ratio in fruit, available P, available K in soil, and fruit Ca concentration. Both N/Ca ratio and Ca/Mg ratio in fruit were affected by different fertilization regime, and bitter pit incidence at the end of storage kept acceptable only if N/Ca < 17 and Ca/Mg ≥ 7 at harvest. The commercial fertilization regime turned out to be organic fertilizer in combination with CaSO4 applied in soil in winter, amino acid Ca sprayed in the first month after full bloom, and CaSO4 applied in soil in summer. __________ Translated from Journal of Fruit Science, 2007, 24(1): 6–10 [译自: 果树学报]  相似文献   
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