旋耕埋草机立刀设计功能实现程度的分析

以1GMC-70型船式旋耕埋草机立刀为研究对象,分析立刀设计功能,建立立刀刃口函数曲线,并利用Matlab软件进行立刀运动学分析。结果表明:立刀当前的结构参数不能很好地与其设计功能相匹配,立刀对螺旋横刀切土节距的增加量小于螺旋横刀切土节距的1/3,立刀自身的秸秆切断效应以及辅助螺旋横刀处理秸秆等效应都比较弱;立刀对未耕土壤有破茬作用,但破茬深度约为垡片最大厚度的1/3,破茬效应较小;立刀对刀辊后方已耕土壤几乎没有碎土效应;立刀没有将垡条切断,它只切割了垡条横截面积的40%左右;立刀的4-3-4-3-4焊接排布方式没有增加自身作业机会。田间作业试验表明,旋耕埋草机是否设置立刀对作业效果没有区别,故在当前结构参数下立刀没有实现其设计功能,建议重新设计立刀。     

Effects of Nitrogen Forms on Carbon and Nitrogen Accumulation in Tomato Seedling

Utilization of organic nitrogen （N） is an important aspect of plant N assimilation and has potential application in sustainable agriculture. The aim of this study was to investigate the plant growth, C and N accumulation in leaves and roots of tomato seedlings in response to inorganic （NH4^＋-N, NO3^-N） and organic nitrogen （Gly-N）. Different forms of nitrogen （NH4^＋-N, NO3^--N, Gly-N） were supplied to two tomato cultivars （Shenfen 918 and Huying 932） using a hydroponics system. The plant dry biomass, chlorophyll content, root activity, total carbon and nitrogen content in roots and leaves, and total N absorption, etc. were assayed during the cultivation. Our results showed that no significant differences in plant height, dry biomass, and total N content were found within the first 16 d among three treatments; however, significant differences in treatments on 24 d and 32 d were observed, and the order was NO3^--N 〉 Gly-N 〉 NH4^＋-N. Significant differences were also observed between the two tomato cultivars. Chlorophyll contents in the two cultivars were significantly increased by the Gly-N treatment, and root activity showed a significant decrease in NHa^＋-N treatment. Tomato leaf total carbon content was slightly affected by different N forms; however, total carbon in root and total nitrogen in root and leaf were promoted significantly by inorganic and organic N. Among the applied N forms, the increasing effects of the NH4^＋-N treatment were larger than that of the Gly-N. In a word, different N resources resulted in different physiological effects in tomatoes. Organic nitrogen （e.g., Gly-N） can be a proper resource of plant N nutrition. Tomatoes of different genotypes had different responses under organic nitrogen （e.g., Gly-N） supplies.     

Application of Current Hapten in the Production of Broad Specificity Antibodies Against Organophosphorus Pesticides

Diethylphosphono acetic acid （DPA） was used as a current hapten to generate broad specificity polycolonal antibodies against a group of organophosphorus pesticides. Six New Zealand white rabbits were immunized with immunogens synthesized by the active ester method （AEM） or 1-ethyl-3-（3-dimethylaminopropyl）-carbodimide method （EDC）. The titers of antisera reached 25 600 by AEM and 6 400 by EDC, respectively. Polyclonal antibodies raised against DPA were screened and selected for the competitive indirect enzyme-linked immunosorbent assay （CI-ELISA）. A CI-ELISA for DPA was developed with a detection limit of 3.536 ng mL^-1and an I50 value of 0.182 μg mL^-1. The assay specificity was evaluated by obtaining competitive curves for several structurally related compounds as competitors. The antiserum showed high affinities to chlorpyrifos, diazinon, omethoate, parathion-ethyl and profenofos with I50 of 0.12, 0.15, 0.21, 0.88, 0.97 and 2.5 μg mL^-1, respectively. The results indicate that the assay could be a screening tool for quantitation and semiquantitation determination of the above former five organophosphorus pesticides.     

欧美杨新品种在内蒙古中西部的引种试验1）

为选育出适应内蒙古自治区中西部气候条件的杨树新品种,对引进的16个杨树品种在呼和浩特市土左旗进行区域造林试验,对2、4、10 a等不同林龄的树高、胸径生长量、造林成活率、保存率、抗寒性、抗病虫害等性状的系统分析表明：各品种间树高、胸径、抗寒和抗病虫等性状间存在显著的差异,品种选择是有效的。经过主要性状的多重比较及综合分析,选取银中杨、碧玉杨和京2杨为速生、抗逆优良品种,其树高、胸径生长量与生长较差的863品种相比银中杨分别提高97．27％、90．31％,碧玉杨提高76．27％、66．43％,京2杨提高69．51％、70．19％。这些品种可抗风沙、干旱、冻害、土壤瘠薄,可在轻度盐碱土（ pH值为8．0左右）上正常生长,尚未发现病害、虫害等。因此,将上述品种确定为内蒙古中西部区应引进和栽培的优良品种,可以在生产中推广应用。     

随机交配群体隐性致死纯合基因型出现的平方Logistic模型(英文)

From the random mating population of maize, the relationship between heterosis and albino seedling was analyzed by means of mathematical theory, further the square logistic model for the appearance of lethal recessive homozygous genotype was deduced. The model shows that heterosis can determine the genetic structure and proportion of population. It approves, that the proportion of aa in each generation of maize seedlings shows a similar Logistic curve in growth process till equilibrium, so long as Aa containins lethal gene a from mutation presents heterosis. The ratio of equilibrium state of aa is determined by the ratio of AA-Aa fitness. Heterosis is helpful for the keeping of genetic diversity of population.     

The Removal and Remediation of Phenanthrene and Pyrene in Soil by Mixed Cropping of Alfalfa and Rape

The mechanisms and efficiencies of the removal and remediation of polycyclic aromatic hydrocarbons （PAHs） in soils by different planting patterns with rape （Brassica campestris） and alfalfa （Medicago sativa） were studied by pot experiments in a greenhouse. Results showed that the remediation efficiencies under mixed cropping of alfalfa and rape significantly exceeded those under single cropping when the initial concentrations of phenanthrene and pyrene were at 20.05-322.06 mg kg^-1 and 20.24-321.42 mg kg^-1, respectively. After 70 days plantation of crops, the contents of extractable PAHs in soils under mixed cropping were much lower than those under single cropping. About 65.17-83.52% of phenanthrene and 60.09%- 75.34% ofpyrene was removed from the soils under mixed cropping, respectively, which were averagely 43.26 and 40.38% for phenanthrene, and 11.03 and 16.29% for pyren higher than those under single cropping. Alfalfa or rape did absorb and accumulate PAHs from the soils apparently; the PAHs concentrations in plants monotonically increased with the increase of initial PAHs concentrations in soil; the accumulations of PAHs in plants showed following sequence as roots 〉 above parts, phenanthrene 〉 pyrene and single cropping 〉 mixed cropping at same contamination level. Despite the presence of vegetation significantly enhanced the remediation of PAHs in soils, contributions of abiotic loss, plant uptake, accumulation and microbial degradation was much lower than those of plant-microbial interactions in the process of phytoremediation. Thus plant-microbial interactions are the main mechanisms for the remediation enhancement of soil PAHs pollution under mixed cropping models. Results suggested a feasibility of the establishment of multi-species phytoremediation for the improvement of remediation efficiencies of PAHs, which may decrease accumulations of PAHs in crops and thus reduce their risks.     

Relationship Between Anthocyanin Biosynthesis and Related Enzymes Activity in Pyrus pyrifolia Mantianhong and Its Bud Sports Aoguan

The aim of this article is to study the relationship between biosynthesis of anthocyanin and activities of phenylalanine ammonia lyase （PAL）, chalcone ismoerase （CHI） enzymes in Pyrus pyrifolia. Changes in the level of anthocyanin and the activities of enzymes of anthocyanin biosynthesis including PAL, CHI were studied in the pericarp of Pyrus pyrifolia Aoguan and Mantianhong during the period of pigment formation. Bagging treatment was also carried out to manipulate the synthesis of anthocyanin and the activities of related enzymes during the period of pigment formation. The results demonstrated that the level of anthocyanin of Aoguan was higher than that of Mantianhong. However, the content of anthocyanins has the similar changing trend in Aoguan and Mantianhong, highest anthocyanin concentrations of two varieties appeared in immature fruit and faded toward harvest. Meanwhile, similar changing trends of activities of PAL and CHI were also observed in both varieties. Aoguan has a lower activity of PAL than Mantianhong, whereas activity of CHI in Aoguan was higher than that in Mantianhong. Activity of PAL decreased during the period of pigment formation and was apparently not limiting to color development, whereas CHI activity increased at the same period and was closely related to the synthesis of anthocyanin. The results of bagging treatment showed that bagging treatment inhibited the activity of CHI, as well as the synthesis of anthocyanin, whereas debagging enhanced both the activity of CHI and synthesis of anthocyanin. The activity of CHI in debagging Aoguan pericarp was higher than the untreated Aoguan. However, effect of bagging treatment toward PAL activity was not obvious. Anthocyanin of bagging treated Aoguan decreased toward harvest. The content of anthocyanin of Pyruspyrifolia increased at the beginning of fruit coloration period and decreased toward fruit harvest. Activity of PAL was apparently not limiting to color development, whereas CHI activity was closely related to the synthesis of ant     

瘦素及其长型瘦素受体在雌性小鼠体内的表达

采用免疫组织化学SP染色法对长型瘦素受体在雌性小鼠生殖周期不同阶段的下丘脑、卵巢、子宫中细胞定位和分布进行了研究,并用ELISA方法对小鼠血清中的瘦素浓度进行了检测。结果显示,下丘脑神经元胞质中有棕褐色阳性颗粒,且阳性细胞数量随妊娠日龄增加逐渐增加,妊娠期与间情期阳性细胞数差异显著(P0.05);在卵巢中,卵母细胞胞质中有长型瘦素受体表达,随卵泡的发育,卵泡细胞中免疫反应阳性细胞数量逐渐增加;在胚泡附植期,瘦素受体在子宫腺和子宫内膜上皮细胞中大量表达。妊娠期血清瘦素浓度均高于间情期,且瘦素浓度从间情期到妊娠4日龄,呈上升趋势,妊娠5日龄稍下降,后随妊娠日龄逐渐增加。结果表明,瘦素及其长型受体能够促进卵泡发育,有利于小鼠胚泡的附植。