Response of Mustard to Ethrel Spray and Basal and Foliar Application of Nitrogen

In a field trial conducted during 1992–93 and 1993–94, the effect of basal (B) nitrogen (N) (45 and 60 kg N ha⁻¹) and foliar application (F) of water (W) or 10 kg N ha⁻¹ and 400 or 600 ppm ethrel (E) (2-Chloro ethyl phosphonic acid) at 70 days after sowing was studied on leaf area index and dry mass at 90 days and pod number per plant, seeds per pod, 1000 seed weight, seed yield, oil content and oil vield at harvest of mustard ( Brassica juncea L. Czern & Coss.) cv. T-59. Recommended basal (B) application of 90 kg N ha (BN₉₀) was used as control. On the basis of 2 year data it was found that basal application of 60 kg N and foliar spray of 10 kg N ha ⁻¹ and 600 ppm ethrel gave higher values for growth and yield characteristics and enhanced seed yield and oil yield by 12.5 and 14.8%, respectively over control BN_90.     

在生物经济中发展柞蚕产业

2009亚太国家生物经济会议《亚太生物经济项目册》中有五个蚕业项目,充分显示了我国蚕业在生物经济中的地位和发展潜力。本文引入生物经济的概念,介绍了我国柞蚕生物工程的概况,提出用工业化理念发展蚕业,要用现代信息产业改造传统蚕业,在生物经济领域突破发展柞蚕产业。     

“三线一圆”理念对高等教育工作的启示

借鉴“三线一圆”企业管理理论,把高校看作一个“生产”人才的特殊“企业”,将该理论中用于描绘企业生存和发展美好蓝图的业务线、制度线、声誉线和文化圆这四个抽象的管理元素用于构建高校教育管理的新模式。指出在高等教育工作中,通过强化高等教育事业的业务质量线、制度管理线、品牌声誉线,夯实校园文化内涵圆,从而构建全面造就人,综合发展人,科学培养人这一高等教育管理的系统工程。     

Selenium and vitamin E deficiency in pigs. II. Influence on plasma selenium, vitamin E, ASAT and ALAT and on tissue selenium.

The effect of dietary selenium (Se) and vitamin E (Vit. E) in pigs on Se and Vit. E in plasma and on Se in tissue from liver, heart, m. long, dorsi and m. psoas major was studied; and furthermore was the influence on the enzymes ASAT and ALAT studied.Two levels of Se were used, 0.03 and 0.06 mg Se per kg feed. Within each Se level 2 levels of Vit. E were used, 15 and 45 i. u. per kg feed. This resulted in 4 groups: 1. low Se and low Vit. E; 2. low Se and high Vit. E; 3. high Se and low Vit. E; 4. high Se and high Vit. E.Ten% of all pigs fed low Se, and 4% of the pigs fed low Se and high Vit. E diet died with severe symptoms of Se deficiency. None of the pigs fed the high Se diet died with such symptoms. Plasma Se determinations have been shown to indicate the Se status in pigs almost as accurately as liver Se determination. ASAT and ALAT enzyme determinations were not of any diagnostic value.There was a good agreement between dietary Vit. E level and the corresponding levels in plasma. Oxidized herring oil seems to enhance the Vit. E need.     

不同砧木对藤稔葡萄光合特性的影响

以少毛变叶葡萄191(LDP-191)、LN33、巨峰为砧木,藤稔为接穗,利用CI-310便携式光合测定仪对在自然条件下藤稔葡萄3种嫁接苗和自根苗的净光合速率、蒸腾速率、气孔导度、光合有效辐射和胞间CO2浓度进行了测定。结果表明:3种嫁接苗与自根苗在晴天的净光合速率的日变化均呈双峰曲线,且3种嫁接组合的净光合速率明显比自根苗的净光合速率高;藤稔自根苗的日均气孔导度明显高于藤稔/LDP-191、藤稔/LN33;不同砧木嫁接的藤稔葡萄光合特性有明显差异,而LDP-191砧木与自根苗相比除净光合速率外其他光合指标均有显著性差异,说明LDP-191砧木对藤稔葡萄是较好的砧木。     

生态农业经营模式浅析

生态农业经营是建立在生态环境发展基础上的经济性复合农业系统,不同地区的经营模式是由地域特色所决定的,生态农业经营模式具有多样性、效率性、综合性以及持续性等优势,在经营模式中能够将经济与生态的有效循环体现出来。为实现生态农业经营的发展与经济效益的最大化,现就生态农场的经营模式进行分析,并找出主导现代农业发展的因素与生态农业发展经营的方向。     

帆式张网渔船渔业经营状态的实证研究

帆式张网是东海渔业区的主要捕捞作业渔具。本论文根据37艘不同功率帆式张网渔船1999－2000年的渔业生产实态，按功率大小分类汇总了不同渔船生产成本，非生产成本，产值和利润等经济指标，比较分析了不同功率渔船的成本和效益。同时，还讨论了税费和资金成本对渔船经济效益的影响，比较分析了不同功率渔船的经营效果。     

Short-Term Dinoflagellate Bloom in a Shrimp Pond in Bahía de La Paz,Gulf of California

From mid-August to mid-September 1998, a dinoflagellate bloom in a shrimp pond near La Paz, Baja California Sur, was studied. Daily samples were taken of phytoplankton, dissolved oxygen, nutrient concentrations, photosynthetic pigments and proteins. The bloom occurred at temperatures of 29.7 to 33.2?°C. High densities of a Scrippsiella-like dinoflagellate (15.9?×?10⁶ cells/L) occurred on the first day of sampling, reaching a peak of 249?×?10⁶ cells/L on Day 13, and declining to 4 to 7?×?10⁶ cells/L by Day 26. Chlorophyll a varied from 8.63 mg/m³ on Day 4 to 141.38 mg/m³ on Day 13. Total nitrogen varied widely (0.2–11.50 μM) while phosphates peaked only once on Day 13 (4.14 μM). Proteins ranged from 523 to 6387 μg/L; the latter value occurred two days after the maximal peak of nitrates and coinciding with the highest level of phosphates. Fertilizers added to the ponds increased nutrient concentration and stimulated phytoplankton growth. In turn, the food supply to cultured shrimp noticeably increased throughout the bloom.     

不同温度对九孔鲍能量收支影响的研究

在摸拟自然条件下,设定5个温度梯度（15、19、23、27、3lac）进行了室内水族箱养殖,结果表明,九孔鲍（Haliotis diversicolor superrtesxa）的生长能和代谢能随温度的增加而增加,高于此温度时则相反,呈负相关关系。在温度为27℃时,九孔鲍的生长能占摄食能的比例达到最大值。九孔鲍在各温度下的能量收支方程为：15℃：100（C）=18．05（F）＋8．00（U）＋7．91（M）＋39．60（R）＋7．14（Psh）＋9．36（Pg）＋9．94 19℃：100（C）=19．89（F）＋12．24（U）＋7．97（M）＋33．74（R）＋6．62（Psh）＋9．54（Pg）＋10．01 23℃：100（C）=17．43（F）＋12．93（U）＋7．04（M）＋33．79（R）＋6．20（Psh）＋10．25（Pg）＋12．37 27℃：100（C）=15．56（F）＋11．03（U）＋7．05（M）＋28．53（R）＋13．67（Psh）＋16．12（Pg）＋8．03 31℃：100（C）=18．82（F）＋13．87（U）＋12．52（M）＋38．44（R）＋12．35（Psh）＋13．62（Pg）-9．62从能量收支方程中看出,只有小部分能量用于生长壳,一部分能量用于生长软体肉能,绝大部分能量用于代谢,还有一小部分能量用于排泄、排粪和分泌粘液。     

闽江河口养虾塘水体可溶性有机碳、营养盐和叶绿素a浓度变化特征

为揭示河口区陆基养虾塘可溶性有机碳(DOC)、营养盐、叶绿素a时空动态变化及其生态化学计量特征,在福建省闽江河口鳝鱼滩选择3个陆基养虾塘作为研究对象,于2018年5-10月原位测定养虾塘水温、pH、盐度、溶解氧指标,并采集不同深度水样,实验室测定DOC、可溶性无机氮(DIN)、磷酸盐(PO43--P)、叶绿素a浓度,探讨其主要影响因素。结果表明,养虾塘水体中DOC、DIN、PO43--P和叶绿素a质量浓度分别介于5.73~16.79 mg·L-1、0.04~1.80 mg·L-1、0.03~0.16 mg·L-1和15.02~443.08μg·L-1,均存在明显的时空变化特征;养虾塘水体DOC、营养盐、叶绿素a浓度受到养殖水体水环境参数、人为活动、养殖生物的共同影响;养虾塘水体碳(C)、氮(N)、磷(P)营养元素组成与植物、土壤之间具有相似性,并且表现为碳盈余和氮限制。在养殖过程中,加强对养虾塘水体营养盐和叶绿素a的动态变化监测,通过人为方式调节养虾塘水体C、N、P比率,对于防止养虾塘水体富营养化,促进养虾塘生态系统绿色可持续生产具有重要作用。