《师伏堂日记》所见皮锡瑞之经学观

根据《师伏堂日记》可以窥探皮锡瑞经学观 ,归之为三 :通经致用的为学旨趣、“义理必兼考证”的治经方法和力戒门户的经学立场。皮氏以其治学主张与成就 ,使今文义例之学、典制之学和经世之学融为一体 ,堪称清代今文经学之集大成者。     

稻瘟病抗性基因Pi1和Pi2的聚合及其育种价值分析

水稻稻瘟病的发病受外界条件影响较大,单纯依靠人工接种抗性鉴定比较困难。因此,人工接种抗性鉴定与分子标记辅助选择结合应用对提高抗性育种效率具有重要意义。本研究利用已建立的水稻抗稻瘟病基因Pi1和Pi2显性分子标记,对黑龙江省主栽品种空育131进行分子标记辅助选择,将Pi1和Pi2基因聚合到空育131中,对其原始亲本和不同基因组合聚合后代进行了稻瘟病田间抗性鉴定,对2个抗性基因的聚合效应进行了统计和评价,由此明确了Pi1和Pi2基因在寒地育种辅助选择中的应用价值。     

基于改进Floodfill算法的田垄视觉导航系统

探索在环境多变的田垄中进行视觉导航的方法,针对传统田垄视觉导航方法计算量大且导航效果较一般的问题,为林果作业机器人自主作业能力提供基础,本文提出一种基于机器视觉的田垄导航方法:使用改进的Floodfill算法分割路径信息,通过十字法进行路况分类,进而采用与路况相对应的算法进行导航计算。使用多张路径图片和模拟环境对算法的分割性能和导航能力进行测试,在试验测试中,道路偏移值保持在6 cm内。试验表明,改进Floodfill算法与分类导航法结合的视觉导航方法具有可行性,可为低算力田垄视觉导航方法的探索提供新的方法和思路。     

广谱抗稻瘟病基因Pi9对籼稻的转化研究

通过农杆菌介导法，将由CaMv35s启动子启动的广谱抗稻瘟病基因Pi9转入5个籼稻品种（丰源B、湘晚籼13号、R996、527、1701）的愈伤组织中，所用质粒为pCAMBIA1301，pCAMBIA1301的T-DNA区含有潮霉素（hygmycin）抗性基因和β-葡萄糖苷酸酶（GUS）基因。以潮霉素作为筛选剂对籼稻愈伤组织进行筛选，结果表明，不同品种在转化过程中抗性愈伤率在73．9％～83．3％之间，获得的部分抗性苗经PCR检测为阳性，阳性植株的转化率差异显著，其转化率为5．7％～25．9％之间，对获得的抗性苗和T2代幼苗的根和叶进行GUS组织化学染色分析，有些抗性苗和T2代幼苗的根和叶呈蓝色反应，表明广谱抗稻瘟病基因Pi9基因己整合到水稻基因组并能正常表达。对T2代进行稻瘟病小种接种试验，结果显示了抗性分离。并且建立了一套较为有效的水稻遗传转化体系。     

籼稻1701转Pi9基因株系的遗传分析及抗瘟性鉴定

利用农杆菌介导法将广谱抗稻瘟病基因Pi9导入籼稻品种1701中,得到了大量的T1代和T2代转基因植株.对T2代植株进行遗传分析和稻瘟病抗性鉴定,结果表明,外源基因Pi9已转入到受体基因组中,并在T2代植株中得到表达.     

利用分子标记辅助选择聚合Pi9(t)和Xa23基因

利用分子标记辅助选择将广谱高抗稻瘟病的Pi9(t)基因和全生育期高抗白叶枯病的Xa23基因聚合到同一优良株系中,获得了含双基因的优良株系L10～L13.用来自不同地区的20个稻瘟病小种和中国流行的7个白叶枯病小种及安徽白叶枯病小种对聚合株系进行接菌鉴定,结果显示:聚合Pi9(t)和Xa23基因的株系L10～L13同时抗稻瘟病和白叶枯病;与稻瘟病的供体亲本75-1-127相比,抗性水平相当,均达抗级(R)水平,且抗谱相同;与白叶枯病的供体CBB23相比,对白叶枯病的抗性时期一致,均表现为全生育期抗性,而且抗性水平和抗谱相似.通过田间农艺性状的筛选,获得的双基因聚合系具有较好的农艺性状,可直接应用于生产或作为抗性亲本.     

Assessing the depletion of soil P following sequential extractions with Mehlich-3 and Olsen solutions

We analyzed in soils with contrasting cultivation histories the depletion of P following sequential extractions with soil testing solutions. Soil samples were collected in three experiments in eastern Canada (L’Acadie, Lévis, and Normandin) and P was sequentially extracted 16 times, once daily, using Mehlich-3 (M3) or Olsen (Ol) solution. The cumulative amount of P extracted was 252 mg P_M3 kg^?1 and 77 mg kg^?1 P_Ol for L’Acadie, 212 mg P_M3 kg^?1 and 66 mg P_Ol kg^?1 for Lévis, and 424 mg P_M3 kg^?1 and 83 mg P_Ol kg^?1 for Normandin. The depletion of P was described by a logarithmic function (Y = a ln (N) + b) for P_M3, and a power function (Y = αN^β) for P_Ol. The inorganic P pool decreased in the three soils. The organic P pool did not decrease possibly because soil testing solutions did not directly extract P from this pool. This study demonstrated that laboratory soil testing analysis using M3 or Ol solution principally target P from the inorganic pool, suggesting that P fertilizer recommendations to mineral soils relying on these methods do not account for the potential of the organic P pool to contribute to soil P availability.     

Cotton growth and boron distribution in the plant as affected by a temporary deficiency of boron

The knowledge of nutrient mobility is an important tool to define the best fertilizer management and diagnosis techniques. Patterns of boron (B) mobility in plants have been reviewed, but there is very little information on B distribution and mobility in cotton. An experiment was conducted to study plant growth and B distribution in cotton when the nutrient was applied in the nutrient solution or to the leaves, and when a temporary deficiency was imposed. Cotton (Gossypium hirsutum, Latifolia, cv. IAC 22) was grown in nutrient solutions where B was omitted or not for 15 days. Boron was applied to young or mature cotton leaves in some of the minus B treatments. Root growth decreased when the plants were transferred to B solutions, but there was a full recovery when B was replaced in the nutrient medium. Boron deficiency, even when temporary, reduced cotton shoot dry matter yields, plant height and flower and fruit set, and these could not be prevented by foliar application of B. Because of decreased dry matter production, leaves of deficient cotton plants actually showed higher B concentrations than non deficient leaves. This would be misleading when a mature leaf is sampled for diagnosis. If there is any B mobility in cotton phloem, it is very low.     

Comparison of Iron Oxide–Impregnated Paper Strips with Other Extractants in Determining Available Soil Phosphorus

Abstract

Iron oxide–coated strips (P_i) can serve as a sink to continuously remove phosphorus (P) from solution. In this way, P extraction is analogous to the P absorption by plant roots. The objective of this study was to compare the iron oxide–coated paper strips with other chemical extraction methods to estimate the plant P availability for corn (Zea mays) growing in the greenhouse in some soils of Hamadan province of Iran. Sixteen soil samples with different physicochemical properties were analyzed for available P using Olsen, Colwell, Mehlich‐1, 0.01 M CaCl₂, AB‐DTPA, and 0.1 M HCl methods and p_i. Furthermore, the effects of two P levels (0 and 200 mg P kg^?1) on the plant indices (P uptake, relative yield, and plant responses) were studied in a greenhouse experiment using 10 soil samples. The results showed that the amount of extractable P decreased in the order of 0.01 M CaCl₂<AB‐DTPA<p_i<Olsen<Colwell<Mehlich‐1<0.1 M HCl. The amount of P extracted by the p_i method was significantly correlated with other extractants. The amounts of P extracted by all chemical methods were significantly correlated. The results of a pot experiment showed that the amount of P extracted by the p_i method was significantly correlated with the plant P uptake. However, the other methods were not significantly correlated with P uptake. The results of this experiment showed that p_i method was able to predict the plant availability of soil P.     

水稻稻瘟病抗性基因Pi ta的SNP检测方法

 针对稻瘟病抗性基因Pi ta位点上的抗感基因的编码产物仅有1个氨基酸的差异,利用已经建立的检测该基因的SNP方法以及作者在该基因编码序列构建的四引物扩增受阻突变体系PCR,对62份2012年长江上游国家水稻区域试验材料和97份陕西省水稻区域试验材料进行了Pi ta基因检测,2种分子标记检测结果一致。该方法的检测结果真实可靠,可以用于检测水稻Pi ta基因位点。