怀山药生长土壤的研究

采用野外调查与室内分析相结合的方法。研究了怀山药生长土壤的分布概况、类型、物理性质、化学性质等。不同土种,不同的理化特性,怀山药品质不同。砂壤土、小两合土、淤土、褐土化两合土4个土种中,以褐土化两合最适宜怀山药的生长,其在质地、土壤结构、砂粘比例、土壤耕性、养分状况等方面均为理想,所产怀山药产量高,品质佳。     

氮钾锌肥配施对玉米地上部分养分的积累与分配的影响

选用对玉米产量有重要作用的氮和被称作为品质元素且与氮有明显交互作用的钾, 以及在北方地区植物和人体共同缺乏的锌为肥源因子, 采用二次通用旋转回归组合设计的试验方法, 定量探讨了氮、钾、锌肥配施对玉米地上部分氮、钾、锌含量和分布的影响, 为北方地区玉米高产、优质提供合理施肥依据。     

School food environments and the obesity issue: content,structural determinants,and agency in Canadian high schools

To understand the phenomenon of the rapidly increasing prevalence of overweight and obese children and youth, it is especially important to examine the school food environment, the role of structural factors in shaping this environment, and the resulting nutrition and health outcomes. The paper examines research on school food environments in the US and Canada. It notes evidence of widespread availability of poor nutrition products in both environments and delineates reasons for the situation, and examines initiatives presently being undertaken in a number of jurisdictions in both countries to encourage healthy eating in schools. Empirical data are presented from a pilot study of high schools in the Canadian province of Ontario. The study documents the extent of student purchasing of nutrient-poor foods and beverages, and the structural factors internal and external to the school that appear responsible for the availability of such products in food environments in this critical institutional sphere. The paper also examines positive local initiatives in high schools that seek to encourage healthy eating in schools.

提高梅花鹿再生茸产量的研究

于１９９０年３月－６月分别在黑龙江省海林县三部落鹿和吉林省松花湖鹿场进行试验。用止血，提高动物营养和人工降雨增加鹿舍相对湿度的三种方法对梅花鹿再生茸生产生长的影响和潜力进行了研究。研究结果表明：单纯进行锯茸止血或提高动物营养对再生茸的产量没有明显影响（Ｐ＞０．０５）；在止血和提高动物营养的基础上同时进行人工降雨，可明显中再生茸的产量１７５±２８ｇ（Ｐ＜０．０１），使锯口愈合时间提前４．６±０．４ｄ     

常见落叶果树果实矿质营养的研究现状

矿质营养是果树生长发育、产量和品质形成的物质基础,对产量的形成和品质的改善有重大影响。本文主要综述了北方常见落叶果树果实矿质营养的变化规律、不同矿质元素及叶片、土壤矿质元素对果实产量和质量的影响,为今后果树矿质营养研究提供一定的理论依据。     

Distribution of Leaf Color and Nitrogen Nutrition Diagnosis in Rice Plant

Greenness and nitrogen content of each leaf on main stem of different japonica and indica ricevarieties under different nitrogen levels were investigated. Results showed that the fourth leaf from the top ex-hibited active changes with the change of plant nitrogen status. When the plant nitrogen content was low, itscolor and nitrogen content were obviously lower than those of the three top leaves. With the increase of plantnitrogen content, the color and nitrogen content of the fourth leaf increased quickly, and the differences ofcolor and nitrogen content between the fourth leaf and the three top leaves decreased. So, the fourth leaf wasan ideal indication of plant nutrition status. In addition, color difference between the fourth and the third leaffrom the top was highly related to the plant nitrogen content regardless of the variety and development stage.Therefore, color difference between the fourth and the third leaf could be widely used for diagnosis of plantnutrition. Results also indicated that the minimized color difference between the fourth and the third leaf at the criticaleffective tillering, the emergence of the second leaf from the top, and the heading was the symbol of high yield. Plantnitrogen content of 27 g kg-1 DW for japonica rice and 25 g kg-1 DW for indica were the critical nitrogen concentrations.     

微量元素铬的营养研究进展

铬是动物的必需微量元素之一,是葡萄糖耐量因子的重要活性组成成分,铬通过葡萄糖耐量因子(GTF)协同胰岛素的作用,影响碳水化合物、脂类、蛋白质和核酸代谢,进而影响动物的生长、免疫、繁殖和胴体品质,降低应激,改善机体免疫机能,提高畜禽生产性能和繁殖力。本文通过对铬的理化特性、铬在动物体内的吸收、运输、贮存和排泄、铬的生物学功能以及铬在动物生产性能上的作用、铬的需要量等方面进行了综合阐述,指出其广阔的应用前景及发展方向。     

Effect of Euchsaena mexicana Schrad Diets on Nutrient Digestibility and Nitrogen Metabolism for Wulong Goose

One trial was conducted to study nutrition digestibility of Euchsaena mexicana Schrad (EMC) diets for Wulong Goose.Thirty-two geese of 9 months old were selected and divided into four groups randomly, with eight geese in each group.Four groups were fed with the isocaloric and isonitrogenous diets of different EMC contents (12, 19, 25 and 31%),respectively. The results showed that, as dietary EMC increased, dry matter (DM) digestibility was decreased significantly,meanwhile the digestibility of crude fiber (CF), neutral detergent fiber (NDF) and acid detergent fiber (ADF) increased significantly (P＜0.05). The ratio of apparent essential amino acid (EAA) digestibility (except Leu) among the four groups had significant difference (P＜0.01). the content of NH3-N in feces dropped (P＞0.05). There were no significant differences in net protein utilization (NPU), N apparent digestibility, N deposition and Ca apparent digestibility in different groups (P＞0.05). The apparent digestibility of P in different groups elevated, while there was significant difference between group D and A (P＜0.01), and there was significant difference between group D and B (P＜0.05).     

有机,无机态氮肥及施用方法对水稻吸收土壤氮素的影响

两年盆栽试验的结果表明,1.在淹水土壤中施用硝酸钾和尿素(1986),均有促进水稻吸收土壤氮素的作用,分别比不施肥的对照增加3.4％～12.7％和13、0％～28.9％,尿素的效果优于硝酸钾。这两者深施或混施的促进作用均对应优于其表面匀施。2.施用尿素和豆科绿肥箭舌豌豆(1987)后,水稻吸收的土壤氮素,随生育期的进展而不断增加。从六叶期到完全成熟期,水稻吸收的土壤氮占其吸收全氮的百分数,施用尿素的从21.9增至31.0,施用箭舌豌豆的从26.4增至40.8。3.在整个生育期,施用尿素和箭舌豌豆的水稻吸收土壤氮素的绝对量,均高于不施肥的对照。箭舌豌豆促进水稻增加吸收土壤氮素的作用优于尿素。4.淹水植稻,不论有否施用化学氮肥或施用何种形态的氮,都会发生土壤原始氮素的损失;但合理施用有机肥料有利于土壤原始氮素的维持,以及土壤的培肥。     

黄土高原旱地春谷吸肥与土壤供肥规律研究

１９９０～１９９２年在山西榆次市对黄土高原旱地春谷吸肥与土壤耕层供肥规律进行了研究。结果表明，土壤耕层氮磷供给能力动态变化遵循倒Ｌｏｇｉｓｔ１０生长曲线方程变化，钾的供给能力动态变化遵循一次方程变化；谷子不同生育时期吸收氮磷钾动态变化遵循Ｌｏｇｉｓｔ１０生长曲线方程变化；谷子一生随着生育进程对氮磷钾的吸收量逐渐增加，土壤氮磷钾供给量则随着谷子吸收量的增加而减少，即供给能力趋于减弱，氮的吸收高峰与土壤供给高峰基本一致，磷的吸收高峰在土壤供给高峰之后，钾的吸收高峰在土壤第一供给高峰期，孕穗至抽穗阶段是谷子吸收氮磷钾的高峰期；从谷子一生来看，吸收氮磷量小于土壤供给量，钾的吸收量大于土壤供给量。通过分析并对榆次市黄土高原区旱地春谷施肥问题提出新见解，即亩产要达到２００ｋｇ以上应重视施用钾肥。