竹缺爪螨实验种群生命表的研究

在25℃温度条件下，用黄金间碧竹（Bambusa vulgaris cv.vittata)叶饲养竹缺爪螨（Aponychus corpuzae Rimando)，应用生存分析理论和多维矩阵模型组建竹缺爪螨种群生命表，计算得种群主要参数为：内禀增长率rm＝0．0811，净增殖率R0＝5．8368，平均世代长度T＝21．7532d，周限增长率λ=1.0845/d；并分析了种群在不同年龄的生命状态，各发育期重叠情况以及稳定的年龄一阶段分布；最后讨论了应用这2种方法组建螨类生命表的优点。     

Photosynthate Unloading from Seed Coats of Phaseolus vulgaris L. an Attempt to Define Conditions Required for Stimulation by Abscisic Acid and Benzylamino Purine

The instablity of the stimulation of photosynthate unloading from seed coats of Phaseolus vulgaris by abscisic acid (ABA ) and benzylamino purine ( BAP ) was studied in terms of experimental conditions. ABA stimulated photosynthate unloading at pH 6 and pH 8 without close dependence upon pH. ABA at a concentration range of 10-5-10-4 mol/L displayed stimulatory effect. However, BAP revealed no effect at a concentration range of 10-6-10-4 mol/L. Experiments designed with different transport time of 14C-photosynthate indicated that ABA might act at the plasma membrane of the unloading cells. Reducing endogenous ABA level by diminishing leaf area did not facilitate the manifestation of exogenous ABA function. Potassium ion stimulated photosynthate unloading from seed coats with highest promotion at 100 mmol/L K . However, no dependence of ABA stimulation of photosynthate unloading on K was found.     

Genetic variability within Phaeoisariopsis griseola from Central America and its implications for resistance breeding of common bean

The genetic and virulence variability of 112 isolates of Phaeoisariopsis griseola , collected from various locations in Central America, were studied using seven random amplified polymorphic DNA (RAPD) primers and 12 common-bean differential genotypes. Broad molecular diversity ( H  = 0·92) among isolates was found using RAPD markers. Fifty pathotypes were identified on 12 differential bean genotypes, 29 of which were represented by only one isolate. Only 18 pathotypes were found in two or more countries. Pathotype 63-63 was the most virulent and caused leaf spots on all 12 common-bean differential genotypes. Comparison of virulence phenotypes and RAPD profiles to known Andean P. griseola isolates confirmed that all isolates belonged to the Mesoamerican group. Pairwise comparison between individual RAPD loci showed that the majority were in gametic phase linkage disequilibrium, revealing that P. griseola maintains a genetic structure that is consistent with asexual reproduction. The molecular and virulence diversities of P. griseola isolates from Central America imply that using single resistance genes to manage angular leaf spot is inadequate and stacking resistance genes may be necessary to manage the disease effectively.     

引起糖甜菜细菌性叶斑病的萎蔫短小杆菌新致病变种

 1995年在内蒙古临河市新发现了糖甜菜细菌性叶斑病,从病斑所分离的10个细菌菌株经柯赫氏法则验证,均确系该病的病原菌。采用形态观察、表型特征和生理生化特性测定、数值分析、血清学反应、细胞化学成分分析、DNA G+C mol%和DNA-DNA同源性测定进行了鉴定,并与植物病原棒形细菌15个标准菌株进行了比较。该病原菌为革兰氏阳性细菌,不规则短杆状,有一根鞭毛、亚极生或侧生,结合其生理生化特性、细胞化学成分和DNA G+C mol%和DNA-DNA同源性测定结果,认为应属于短小杆菌属(Curtobacterium)的萎蔫短小杆菌(Cur. flaccumfaciens),数值分析也支持这一结论。此外,据血清学反应结果及其对短小杆菌属的其它植物寄主的致病情况,认为该病原菌应是萎蔫短小杆菌种下的一个新的致病变种,定名为Curtobacterium flaccumfaciens pv. beticola pv. nov. Chen et al.,2000(萎蔫短小杆菌糖甜菜致病变种)。     

The effect of populations of Xanthomonas campestris pv. phaseoli in bean reproductive tissues on seed infection of resistant and susceptible bean genotypes

Surface and internal populations of Xanthomonas campestris pv. phaseoli, causal agent of common bacterial blight of bean, on and in flower buds, blossoms and pods of seven bean (Phaseolus vulgaris) genotypes were studied. Bean plants were grown in the field and artificially inoculated at the seedling stage (18 days old). The pathogen was recovered in high numbers from flower buds, blossoms, pods and seed of both resistant and susceptible bean genotypes. Significant differences (P = 0.05) in population levels of X. c. pv. phaseoli between stages of reproductive tissue development were observed. Infected seed from resistant bean genotypes had no visible symptoms. Such seed may play an important role in the epidemiology of common bacterial blight because they are difficult to detect and may occur at low frequency in seed lots, as was the case in the current study.     

山杏种皮黑色素的抗氧化活性

对山杏种皮黑色素的抗氧化活性进行评价.结果表明:山杏种皮黑色素可以显著抑制β-胡萝卜素的氧化褪色,其清除自由基活性具有量效性,清除羟自由基能力与2,6-二叔丁基对甲酚(BHT)无显著差异而高于抗坏血酸(VC),清除超氧阴离子能力超过BHT和VC.山杏种皮黑色素既可以作为氢供体,清除DPPH自由基,但清除能力低于BHT和VC,也可作为电子供体,其还原能力高于BHT和VC.     

甜菜源库关系的研究

为阐明源、库的关系对甜菜产量形成的影响。运用比较生理学的方法,研究了不同特性甜菜品种群体源、库的形成及其相互关系以及源、库发展在产量形成中的作用。结果表明,甜菜群体LAI和LAD可作为衡量源大小及能力的重要指标。光合源的同化能力直接影响着块根库容的大小,后期较大的光合源会抑制块根库的扩大,影响甜菜产量的形成。揭示了丰产、高糖甜菜品种的源库关系,LAI峰值出现在块根及糖分增长期,最大LAI应在4.3以上,达到峰值后要有20 d左右的相对稳定持续期,糖分积累后期LAI应保持在2.4左右。群体LAD应在块根及糖分增长期达到19.3 m2.d以上,后期呈缓慢下降变化。以上结果可为指导甜菜生产实践提高产量提供理论依据。     

Chestnut (Castanea sativa Mill.) genotype identification: An artificial neural network approach

Summary

The potential use of the artificial neural networks (ANNs) for characterization and identification of seventeen chestnut (Castanea sativa Mill.) accessions, belonging to the ``marrone''-type and ``chestnut''-type, was investigated in genotypes originating from regions of Italy. Different back-propagation neural networks (BPNN) were built on the basis of image analysis parameters of the leaves, for two tasks of chestnut classification. In the first case a BPNN was built and trained to differentiate the 17 accessions of chestnut. In the second case a BPNN was conceived to distinguish between the ``marrone'' and ``chestnut'' types. BPNN produced a clear identification of all the accessions except in the case of `Garrone nero', `Garrone rosso' and `Tempuriva', which showed almost the same output diagram. Cluster analysis separated the 17 chestnut genotypes into four main groups whose differences were related to the original sources of the genotypes and to the type of affiliation (``marrone''-type or ``chestnut''-type). Artificial neural network technique was also able to discriminate between ``marrone''-type and ``chestnut''-type accessions. Qualitative and quantitative rules for the image analysis parameters, useful for classifying chestnut accessions into these two types, were obtained. On the whole the relative importance of the leaf parameters reveals that ``typical'' leaves for ``marrone''-type are more elongated, of a darker colour and with a higher perimeter/area ratio than the leaves of the ``chestnut''-type.     

三种香料蔬菜的营养及挥发性物质分析

对百里香、罗勒、龙蒿草3种香料蔬菜的营养物质含量及挥发性化学物质成分进行了分析,并与普通蔬菜的文献值进行比较。结果表明:3种香料蔬菜的蛋白质、碳水化合物及无机营养元素钙、铁、锌和硒、维生素C含量比普通蔬菜高,而脂肪、胡萝卜素含量与普通蔬菜相比无明显差异。     

内蒙古普通菜豆枯萎病病原菌鉴定

<正>普通菜豆(Common bean),俗称芸豆(Kidney bean),为豆科(Fabaceae)菜豆属一年生草本植物,营养丰富,蛋白质含量高,既是蔬菜又是粮食,是重要的农副产品。内蒙古自治区是我国种植普通菜豆的主要地区之一。随着普通菜豆栽培面积以及连作年限不断增加,病虫害问题日益突出,尤其是枯萎病,严重影响了普通菜豆的产量和品质,已成为限制普通菜豆产业可持续发展的主要因素之一。2021年7月,