鸡毒支原体活疫苗的保存期测定

将鸡毒支原体弱毒冻干疫苗和湿苗分别在不同温度下保存,然后分别在不同时间内测定其活菌数和鸡体内免疫效力测定。活菌数测定结果表明：鸡毒支原体冻干疫苗在－２５℃的条件下保存１１．５个月,活菌数维持不变;在－１５℃保存９．５个月,活菌数下降一个滴度;在４℃～１０℃条件下保存８．５个月,活菌数不变。湿苗（培养物）的室温２４℃保存４ｄ,活苗数不变,保存５ｄ活菌数下降两个滴度;在３２℃保存４８ｈ活菌数不变,保存     

Orychophragmus violaceus, a Potential Edible-oil Crop

Orychophragmus violaceus, a member of the Cruciferae family, has been found to have a high oil quality with high contents of palmitic (14.3 %) and oleic (20.3 %) acids, and lower contents of linolenic (4.8 %) and erucic (0.9 %) acids. Plants of O. violaceus exhibit a high number of branches, pods per plant, and seeds per pod, which contributes to the high yield potential of this plant. Individual selection was made in the original population of O. violaceus, and a few early, disease-tolerant and high-yielding lines were obtained. Intergeneric hybridization was performed between B. napus and O. violaceus and several hybrid plants (F₁) were obtained. After treatment with colchicine, amphidiploid plants developed. O. violaceus shows great potential for becoming an edible oil crop or being used as genetic material in a rapeseed breeding programme.     

真菌对桉树植株的生理影响

在苗圃接种试验基础上 ,对桉树植株营养吸收生理、根系活力进行了研究 ,根系显微观察表明 ,真菌组合在桉树根系上形成了混合菌根 ,即 :PG[彩色豆马勃 (Pisolithus tinctoriux ) X苏格兰球囊霉 (Glomus caledonium ) ]。接种菌根菌对桉树植株营养生理产生显著影响 ,接种组合 PG不仅促进植株对 N、P、K和 B的吸收 ,还有利于提高苗木的根系活力和 ABA的含量     

影响甘蓝型油菜与诸葛菜远缘杂交结实率的几个因素

在甘蓝型油菜（Brassicanapus）与诸葛菜（Orychophragmusviolaceus）属间远缘杂交授粉子房离体培养研究中，观察到不同杂交组合和不同类型的培养基对杂交结实率均有明显影响。     

二月兰传粉生物学研究

对二月兰在北京地区开花的物候期、花粉的活性、柱头的可授性、植株繁育系统及种子的萌发特性等方面进行研究,结果表明:二月兰的花期从3月底可一直到5月中旬,盛花期在4月,单朵花期维持5 d左右,5月中旬花朵基本凋谢,进入结实期;花粉活性蕾期最高,开花第4天基本无活性,而柱头可授性在开花后3～4 d最高;不同方式的结实率也表明二月兰自然条件下难于自花授粉;二月兰的种子储藏年限及温度对萌发率有一定的影响,尤其对萌发速度影响较大,2005年收集的种子较于2003年和2004年萌发更快,而在25℃下萌发速度比20℃和30℃更快.     

Use of Fourier-transform infrared spectroscopy to quantify immunoglobulin G concentration and an analysis of the effect of signalment on levels in canine serum

Deficiency in immunoglobulin G (IgG) is associated with an increased susceptibility to infections in humans and animals, and changes in IgG levels occur in many disease states. In companion animals, failure of transfer of passive immunity is uncommonly diagnosed but mortality rates in puppies are high and more than 30% of these deaths are secondary to septicemia. Currently, radial immunodiffusion (RID) and enzyme-linked immunosorbent assays are the most commonly used methods for quantitative measurement of IgG in dogs. In this study, a Fourier-transform infrared spectroscopy (FTIR) assay for canine serum IgG was developed and compared to the RID assay as the reference standard. Basic signalment data and health status of the dogs were also analyzed to determine if they correlated with serum IgG concentrations based on RID results.Serum samples were collected from 207 dogs during routine hematological evaluation, and IgG concentrations determined by RID. The FTIR assay was developed using partial least squares regression analysis and its performance evaluated using RID assay as the reference test. The concordance correlation coefficient was 0.91 for the calibration model data set and 0.85 for the prediction set. A Bland–Altman plot showed a mean difference of −89 mg/dL and no systematic bias. The modified mean coefficient of variation (CV) for RID was 6.67%, and for FTIR was 18.76%.The mean serum IgG concentration using RID was 1943 ± 880 mg/dL based on the 193 dogs with complete signalment and health data. When age class, gender, breed size and disease status were analyzed by multivariable ANOVA, dogs <2 years of age (p = 0.0004) and those classified as diseased (p = 0.03) were found to have significantly lower IgG concentrations than older and healthy dogs, respectively.     

Measuring soil disturbance effects and assessing soil restoration success by examining distributions of soil properties

Successful restoration of an ecosystem following disturbance is typically assessed according to similarity between the restored site and a relatively undisturbed reference area. While most comparisons use the average or mean parameter to represent measured properties, other aspects of the distribution, including the variance of the properties may assist in a more robust assessment of site recovery. Our purpose was to compare soil properties in different ages of reclaimed soils with those in reference areas by incorporating the potentially different distributions according to areas. On two sampling dates, in consecutive years, we examined soil properties on a chronosequence of reclaimed natural gas pipelines spanning recovery ages of <1–54 years, obtaining data on soil moisture, organic carbon, nitrogen, electrical conductivity, pH, and microbial abundance. To make the comparisons, we analyzed our data with a Bayesian hierarchical linear mixed model and obtained posterior predictive distributions for the soil properties. This allowed us to probabilistically quantify the extent to which a soil property from a reclaimed treatment was similar to that from an undisturbed reference. We found that the posterior predictive variance of most soil properties was particularly sensitive to disturbance and reclamation, especially, within the first few years of recovery. Response of this variance to disturbance, reclamation, and recovery was not necessarily accompanied by a shift in the posterior predictive mean value of the property. Patterns for all soil properties changed over time, with posterior predictive distributions of soil properties generally becoming more similar to those of the undisturbed reference sites as recovery time increased. We suspect these trends in altered variability coincide with the degree of spatial heterogeneity in soil properties that results following disturbance and reclamation, which is also coupled to patterns of vegetation recovery.     

土壤生物炭的生产：三种窑模型的比较研究

Biochar has potentials for soil fertility improvement, climate change mitigation and environmental reclamation, and charred biomass can be deliberately incorporated into soil for long-term carbon stabilization and soil amendment. Many different methods have been used for biochar production ranging from laboratory to industrial scales. However, in countryside of developing countries,biomass is generally used for cooking but not charred. Biochar production techniques at farmer scale have remained poorly developed.We developed and tested biochar production kilns for farmers with a dimension of 50.8 cm × 38.1 cm(height × diameter), using three different setups for optimizing oxygen(O2) limitation and syngas circulation: airtight with no syngas circulation(Model I),semi-airtight with external syngas circulation(Model II) and semi-airtight with internal syngas circulation(Model III). A comparative assessment of these biochar production kiln models was made considering biochar pyrolysis time, fuel to biomass ratio, biochar to feedstock ratio and thermogravimetric index(TGI). Among the models, the best quality biochar(TGI = 0.15) was obtained from Model I kiln taking the longest time for pyrolysis(12.5 h) and the highest amount of fuel wood(1.22 kg kg-1biomass). Model III kiln produced comparatively good quality biochar(TGI = 0.11), but with less fuel wood requirement(0.33 kg kg-1biomass) and shorter pyrolysis time(8.5 h). We also tested Model III kiln in a three times larger size under two situations(steel kiln and pit kiln). The biochar to feedstock ratio(0.38) and quality(TGI = 0.14) increased slightly for the larger kilns. Quality of biochar was found to be mainly related to pyrolysis time. The costs for the biochar stove and pit kiln were US$ 65–77, while it was US$ 154 for the large size steel kiln. Model III kiln can potentially be used for both cooking and biochar production at farmer scale.     

Modeling the effects of microfluidization conditions on properties of corn bran

Corn bran was microfluidized through a 200-μm channel in the pressure range of 124.1–158.7 MPa for 1–5 passes following the central composite experimental design. Physicochemical properties and antioxidant properties of microfluidized bran samples were measured and fitted to the second order polynomial model. The response surface equations obtained showed that all the properties examined had a positive linear relationship with pressure and a negative quadratic relationship with number of passes except for ABTS radical scavenging activity which was quadratically related to both processing parameters. The number of passes generally had a more pronounced effect on the examined properties compared with pressure. Within the experimental range, the maximum values of swelling capacity, water-holding capacity, and oil-holding capacity were respectively 10.62 ml/g d.w. (at 158.7 MPa), 5.49 g water/g d.w. (at 158.7 MPa), and 4.61 g oil/g d.w. (at 124.1 MPa); the maximum values of surface reactive phenolic content, DPPH and ABTS radical scavenging activities were 148.80 mg/FAE g d.w. (at 158.7 MPa), 50.02 μmol TE/g d.w. (at 158.7 MPa), and 47.90 μmol TE/g d.w. (at 145.9 MPa), respectively. All maximum values of the properties occurred at 5 passes.     

Clearfield® rice: Its development,success, and key challenges on a global perspective

Weedy rice (Oryza sativa) is a close relative of domesticated rice and a noxious weed prevalent in rice fields in world regions where rice is grown. Weedy rice management has remained challenging to farmers, mainly due to the weed's physiological and morphological resemblance to rice cultivars. The introduction of Clearfield^® rice provides an alternative solution and an additional tool for integrated weed management. Clearfield^® rice-based programs result in the cleanest rice fields in the southern U.S. However, persistent application of the imidazolinone herbicides (imazethapyr, imazamox, and imazapic) in Clearfield^® rice raises concerns about the possible evolution of resistance to ALS-inhibitor herbicides in weedy rice and the transfer of resistance trait. The risk of resistant weedy rice evolution is much higher in Asia, Latin America, and other tropical regions where there is no winterkill and rice is planted at least twice each year. Herbicide carryover to rotational crops is also a concern. We summarized the progress of commercialization of Clearfield^® rice in 15 countries across the continents of America, Asia and Europe. In some countries, imidazolinone-resistant weedy rice outcrosses have been found abundant, thereby negating the utility of Clearfield^® technology. The persistence of imidazolinone herbicide residues in the soil is a concern in regions where multiple crops are planted in a year, or the following year. These challenges should be anticipated by countries that are considering adopting Clearfield^® rice technology. Issues associated with gene escape, resistance evolution in weedy rice, and herbicide carryover to rotational crops remain to be resolved. Research to achieve sustainable solutions for weedy rice management, must be continued and intense educational programs for growers must be sustained.