新型包膜缓释尿素在辣椒上施用效果的研究

为探讨自行研制的有机无机复合物包膜缓释尿素的缓释性能及对作物生长发育的影响,进行辣椒小区田间试验。结果表明,包膜缓释尿素处理辣椒的椒长、椒肩宽、总产量比常规施肥分别增加15.8%、26.2%、12.4%,包膜缓释尿素用量减少20%的条件下,椒肩宽、总产量比常规施肥增加10.9%、3.3%;等氮量包膜缓释尿素和包膜缓释尿素减量20%处理辣椒果实中NO3--N含量比常规施肥减少41.7%和44.2%;在辣椒整个生长期内施用包膜缓释尿素处理土壤中的全N含量保持在100 mg kg-1左右。综上,有机无机复合物包膜缓释尿素能够达到持续供应作物养分,促进作物生长发育,降低硝酸盐含量,提高产量的目的。     

Studies on Blended Urea for Nitrogen Economy in Grain Sorghum

A field experiment was conducted with sorghum variety CSH-9 in kharif season of 1983 and 1984 to find out the efficiency of coated urea fertilizers over urea alone. The coated urea fertilizers used were neem cake coated urea, neem extract coated urea, coaltar coated urea, 10% didin coated urea along with ordinary urea. Four rates of urea application viz 50, 100, 125 kg N/ha were used along with control in single and split application.
The dry matter yield was recorded to be higher with ordinary urea at initial growth stage of sorghum. However the coated urea fertilizers recorded more dry matter at advancing growth stages. The dry matter accumulation increased with increasing N rates. Split application of N registered higher dry matter. The grain yield was increased due to coating of fertilizers. The neem cake coated urea and 10 % didin coated urea produced highest grain yield which was about 1.5 times more over urea alone. The grain and fodder yields were increased with increasing N rates, the highest yields being with 120 kg N/ha application. N concentration in plant was decreased with advancing growth stage. The concentration, uptake and N recovery were highest with 10% didin coated urea in 1984 and with neem cake urea in 1983. Coated urea fertilizers and split application of N resulted in increasing the N use efficiency over single application.     

MAGNETIC RESONANCE IMAGING OF SPONGY DEGENERATION OF THE CENTRAL NERVOUS SYSTEM IN A LABRADOR RETRIEVER

A 7-month-old, neutered female Labrador Retriever was evaluated for tetraparesis and subtle cerebellar dysfunction. Clinical signs progressed over a period of 6 weeks to severe ataxia, hypermetria, intention tremors, and finally non-ambulatory tetraparesis. On magnetic resonance imaging of the brain there were large, bilaterally symmetrical, ovoid lesions in the region of the deep cerebellar nuclei that were hyperintense on T2-weighted and proton density images and hypointense on T1-weighted images. There were similar but smaller bilaterally symmetrical lesions present within the thalamus. Euthanasia was performed and lesions consistent with the previously described spongy degeneration of Labrador Retrievers were identified. This disease and its relation to similar human heritable leukodystrophies are discussed.     

包膜控释肥料在土壤中养分释放特性的测试方法与评价

在土壤培养基础上,着重研究了包膜控释肥料养分释放率的三种测定方法以及在土壤中测得的包膜控释肥料养分释放率与在水中测得的养分释放率间的相关性。结果表明,在土壤培养中,采用肥料养分化学测定法、肥料养分称量法和土壤无机氮增量法都能直接或间接表征包膜控释肥料在土壤中的养分释放率及其相关性状。包膜控释肥料在土壤与水两种体系中所测得的养分释放率之间相关性显著,其相关关系符合一元一次线型回归方程,相关系数(r)大于0.920。     

Effect of long-term field exposure of soil to acetylene on nitrification,denitrification, and acetylene consumption

Coated CaC₂ is a newly developed product which can supply nitrification-inhibiting quantities of C₂H₂ (1–10 Pa) to the soil, throughout a cropping season. This method of applying C₂H₂ to the soil maintains C₂H₂ in the soil continuously for several months. It is not know whether these low C₂H₂ concentrations alter soil microbial processes. A field study was initiated to determine the effect of supplying C₂H₂ to a clay soil, using coated CaC₂, on soil respiration, denitrification, nitrification, and C₂H₂ consumption. The C₂H₂ consumption rate increased with length of soil exposure to C₂H₂ (r ²=0.59). The rates of CO₂ production (r ²=0.88) and denitrification (r ²=0.86) were both highly correlated with the C₂H₂ consumption rates. The nitrifier potential decreased to a minimum of 21% of the control after 3 months of C₂H₂ treatment. After this time, nitrifier activity increased to 41% of the control after 11 months of treatment. This increase was due to increased C₂H₂ consumption in the soil. After 3 months of continuous application of C₂H₂ to the soil, the C₂H₂ concentrations were generally below that necessary to inhibit nitrification. No adaptation to the C₂H₂ by nitrifiers was found. Repeating these measurements 1 year later showed that soils previously exposed to C₂H₂ retained their enhanced C₂H₂ oxidation capacity and the capacity to use C₂H₂ to increase denitrification. Nitrification potentials remained about 50% lower in soils exposed to C₂H₂ a year earlier compared to soils not previously exposed to C₂H₂.     

15%克·福·唑醇悬浮种衣剂芽后包衣对玉米幼苗的生理效应

研究了唑醇类种衣剂芽后包衣对玉米幼苗的生理效应。结果表明,用15%克·福·唑醇悬浮种衣剂芽后包衣处理对玉米幼苗无不良影响,对幼苗根系活力、根的过氧化物酶活性、幼苗叶片叶绿素含量、光合速率及叶肉细胞间隙CO2浓度均有不同程度的提高。以药种比1∶50芽后包衣效果最佳。     

不同包膜控释肥施用对轮作作物养分利用效率的影响

为揭示不同包膜控释肥对轮作作物氮、硫养分利用效率的差异,在池栽条件下,连续2年选用控释掺混肥(SCU+PCU)、硫加树脂包膜控释氮肥(PSCU)和树脂包膜控释氮肥(PCU)在夏玉米-冬小麦体系中,研究不同包膜控释肥对轮作作物籽粒产量的差异及与氮素利用效率和硫素利用效率的关系。结果表明:施用控释掺混肥和PSCU均可明显促进作物生长,增加植株对氮和硫的吸收,使作物氮素利用效率与硫素利用效率协同提高,在保持植株一定氮素和硫素积累量的基础上,通过提高氮素和硫素的收获指数促进籽粒产量的增加,夏玉米季SCU+PCU,PSCU,处理的氮肥利用率均高于Urea处理分别为19.6%,15.65%,实现作物对氮素的高效利用。     

生物质颗粒成型机平模设计的有限元分析

平模是生物质颗粒成型机核心的、最易损坏的部件,主要由加工物料过程中模孔与物料的应力及位移变化引起.通过ANSYS分析模孔直径、模盘厚度及模孔倒角3因素变化时平模模盘模孔与挤压物料的位移和应力变化情况,结果显示,模孔所受应力和位移变化随着模孔倒角的增大而减小,随模板厚度和模孔直径的增大而增大.由此可对模盘模孔的成型参数进行分析,确定模孔成型参数为:模孔倒角80°,模盘厚度40 mm,模孔直径应介于7～8 mm之间.     

A technique for predicting urea release from coated urea in wetland soil

Abstract

A simple technique for measuring urea release from different coated urea fertilizer materials in simulated wetland soil has been developed and tested. The laboratory soil system used simulates physical, chemical, and microbiological environments of wetland soils under field conditions. Laboratory and field values for urea release are in good agreement.     

蟠桃磷脂酶D基因RNAi表达载体构建

[目的]构建蟠桃磷脂酶D基因的RNAi表达载体.[方法]以英格尔蟠桃为材料,将CTAB改良法提取的蟠桃总RNA反转录成cDNA作为模板,通过RT - PCR扩增约347 bp的保守片段,将目标片段插入到pSK - int中间表达载体中,获得pSK - PLD - RNAi中间表达载体,然后将其转入植物双元表达载体pCAMBI1301中,构建该基因的shRNAi表达载体pCAMBIA - PLD - RNAi.[结果]经限制性内切酶酶切和测序鉴定证明蟠桃磷脂酶D基因的RNAi表达载体pCAMBIA - PLD - RNAi已构建成功.[结论]蟠桃磷脂酶D基因的RNAi表达载体的构建为进一步通过RNAi技术延长蟠桃果实的贮藏寿命奠定了基础.