Whitebacked planthopper Sogatella furcifera (Horváth) (Homoptera: Delphacidae) resistance in rice variety Sinna Sivappu

Whitebacked planthopper (WBPH) along with brown planthopper (BPH) has emerged as a major pest of rice in several Asian countries. Development and cultivation of varieties resistant to both planthoppers is an ecologically acceptable strategy to manage these pests. Sinna Sivappu, a Sri Lankan landrace, was reported to be resistant to both planthoppers. While inheritance of BPH resistance has been reported, the genetics of WBPH resistance in this variety is not known. Using a mapping population of 255 F_2:3 families from Taichung Native (TN)1/Sinna Sivappu cross and 128 polymorphic simple sequence repeat (SSR) markers, genes or quantitative trait loci (QTLs) for WBPH resistance quantified in ten phenotypic tests were identified, adopting classical Mendelian segregation, correlation and QTL analyses. The inheritance pattern suggested that a single recessive gene controlled regulation of seedling damage score. Antixenosis or nymphal preference was influenced by two complementary recessive genes, whereas tolerance in terms of days to wilt was under the influence of a single dominant gene. Several of these phenotypic tests recorded high degree of positive or negative correlation between them, suggesting dependence or redundancy of the tests. QTL analysis revealed 13 loci associated with nine traits. Five major-effect QTLs were detected for damage score (chromosome 6), nymphal survival (chromosome 12), and days to wilt (three QTLs on chromosome 4). We suggest involvement of four WBPH resistance genes in Sinna Sivappu, designated as wbph9(t), wbph10(t), wbph11(t), and Wbph12(t). One of the recessive genes could be allelic to any of the recessive genes reported in cluster C on chromosome 6 which might confer resistance to both BPH and WBPH.     

Identification of a novel gene (Apq1) from the indica rice cultivar ‘Habataki’ that improves the quality of grains produced under high temperature stress

The appearance of brown rice grown under high temperature conditions is an important characteristic for improvement in Japanese rice breeding programs. We performed a QTL analysis of the appearance quality of brown rice using chromosome segment substitution lines of the indica cultivar ‘Habataki’ in the ‘Koshihikari’ genetic background. A line carrying a ‘Habataki’ segment on chromosome 7 showed a high percentage of perfect grains produced under high temperature conditions during the ripening period. To verify the role of this segment, and to narrow down the region containing the useful allele, substitution mapping was performed using multiple paired lines. As a result, the chromosomal location of a gene that we named Appearance quality of brown rice 1 (Apq1) was delimited to a 48-kb region. In addition, we developed an Apq1-near isogenic line (NIL) to evaluate the effect of Apq1 on various agronomic traits. Under high temperature conditions during the ripening period, the Apq1-NIL produced significantly higher percentages of perfect grains than ‘Koshihikari’. Other agronomic traits, including yield and palatability, were similar between the Apq1-NIL and ‘Koshihikari’. Therefore, the ‘Habataki’ allele of Apq1 will be useful in breeding programs aimed at improving the quality of grains ripened under high temperature conditions.     

ACTA AGRONOMICA SINICA Vol.21(1995)

NO.lADtails[IcallecnnlqueanQooeneralIZClZCQLomDu比rboltwareforIntefValMaDDln巴otUuantltatlvelraltLociandItsApplication…………………………………………………XuYunbl,ShenZOngta口,ChenYing,ZhULihuang（8）AnInquiringIntotheNeafostNeighbollTingAnalysisforTmils     

Does the influence of the epibenthic predator crangon crangon L. (brown shrimp) extend to sediment microalgae and bacteria?

The effect of juvenile Crangon crangon L. (brown shrimp) on the microbial part of the food web of marine shallow-water sandy sediment was investigated in two experiments using an outdoor flow-through system. Biomass, composition and productivity of microalgae and bacteria, POC and PON content in the sediment, as well as nutrient and oxygen fluxes, were measured in the absence and presence of two natural densities (50 and 100 ind·m⁻²) of juvenile Crangon. Stimulating effects of the presence of juvenile Crangon on both microalgae and bacteria were observed after three weeks. However, the number of statistically significant effects was low, despite the conspicuous change in sediment characteristics caused by Crangon activity. To explain the possible trophic effect of Crangon via meiofaunal grazing, the results were compared with meiofaunal grazing rates (dual labelling by ¹⁴C-bicarbonate and ³H-thymidine) and changes in the meiofaunal and macrofaunal community. The reasons for the low number of significant trophic effects of Crangon on algae and bacteria were that the overall meiofaunal grazing pressure on microbiota was low, and that only part of the meiofauna (mainly harpacticoid copepods) was significantly affected by the predator. Meiofauna thus appeared to be a weak mediating link in the sandy sediment system investigated. No effect of Crangon on oxygen fluxes, or POC and PON content in the sediment was observed. Neither were the nutrient concentrations in the overlying water affected, but increased nutrient levels in the pore water were observed. According to theoretical calculations, excretion from the shrimp may imply a considerable nutrient addition which can be rapidly re-utilized by the microbes directly at the sediment/water interface. Bioturbation by Crangon appeared to counteract flaking of the microalgal mat.     

Design of the Expandable (I)FFT Implemented in the CPLD

The architecture of scalable length and high speed FFT processor based on CPLD(Complex Programmable Logic Device) is proposed, including the pipeline architecture of the radix mixed FFT algorithm, the address regularity of the read-then-write RAM, the array architecture of short-length FFT and the pipeline complement architecture of CORDIC(Coordinate Rotation Digital Computer) algorithm. If the input-data velocity is 20 MHz,the time expended on 1024-point FFT is 50 us.     

紫花醉鱼草(Buddleja fallowiana Balf.f.et W.W.Smith)种子萌发条件的研究

紫花醉鱼草是主要分布于云南西北部海拔 2 70 0～ 380 0 m的一种野生观赏灌木 ,其种子长圆形 ,褐色 ,周围有翅 ,大小约 0 .5 mm× 0 .5 mm,千粒重 0 .0 5 5 g。在 2 0℃及 2 5℃的发芽温度下第 15 d的发芽率分别为 94%和 98% :在抑制紫花醉鱼草种子发芽的 30℃的温度下 ,180 0 lx～ 30 0 0 lx的人工光照和每日光照 16～ 2 0 h能促进种子萌发。在 2 5℃的发芽适温下 ,照光能使紫花醉鱼草种子萌发提前 1～ 3d。低温高海拔的生境和其种子萌发对高温与光照的需求 ,可能是紫花醉鱼草在自然环境中不能自然繁殖成为蔓延性杂草的原因之一。     

牡丹(Paeonia sect.Moutan)功能基因研究进展

传统的育种和栽培技术在牡丹花色及花型改良、花期延长等方面存在巨大限制,功能基因研究将为解决相关难题提供有效方案。本研究总结了国内外调控牡丹花色、花型、花期、抗逆性等重要性状的功能基因的研究进展,并对目前牡丹功能基因研究所涉及领域、基因挖掘及功能研究采用的方法等方面存在的问题进行了总结,对未来发展方向进行了展望,旨在揭示牡丹重要性状形成及调控的分子机制,为分子育种及相关技术创新提供参考。     

牡丹(Paeonia Sect. Moutan)生物技术育种研究进展

生物技术育种是牡丹品种改良和种质创新的重要手段。本研究从组织培养、遗传多样性、DNA指纹图谱的构建、功能基因、遗传图谱构建等方面总结了牡丹生物技术育种研究进展,并根据存在的问题对未来研究的重点方法、领域及发展的方向进行了探讨。牡丹组织培养研究中,生根依旧是难点,分生结节将成热点。牡丹遗传多样性的研究以及构建指纹图谱和遗传图谱,分子标记开发和应用是重点,全面而准确的DNA指纹图谱的构建以及重要性状QTLs的定位是研究热点。牡丹功能基因研究的重点方向则是基因功能验证及重要性状的分子调节机制。本研究旨在推动牡丹生物技术育种的发展,为相关技术创新、分子标记辅助选择育种及转基因育种提供参考。     

牡丹(Paeonia sect.Moutan)分子标记研究进展

DNA分子标记在牡丹中得到广泛应用,取得了丰富的成果。本研究以分子标记的应用领域为线索,从遗传多样性研究、种质鉴定、栽培种质起源与关系分析、遗传图谱构建等方面总结了分子标记在牡丹各项研究中应用的进展。对未来研究的重点方法及领域进行了探讨,指出牡丹分子标记的开发应以SSR、SNP等为重点,应用领域以品种DNA指纹图谱和分子标记辅助选择育种为重点。本研究旨在推动分子标记技术在牡丹育种中的应用,以提高牡丹的育种效率。     

青海草地早熟禾(Poa pratensis L.cv.Qinghai)近几年的研究进展

论述了青海草地早熟禾(Poa pratensis L.cv.Qinghai)野生栽培品种的由来,以及近几年在生物-生态性、恢复生态学、生理生化和高寒草坪方面的工作,提出了青海草地早熟禾目前依然缺乏的研究,指出今后工作的重点,应加强青藏高原育种工作,寻找更多更好的牧草生态型品种。     

鸢尾属植物马蔺(Iris lactea Pall.var.chinensis)的研究进展

本文从生物学特性、繁殖方法、抗逆性、细胞学和孢粉学、遗传多样性、应用价值等诸多方面对马蔺的研究现状进行了综述.     

Improvements on the Boundary Element Method( I )

This paper presents an improved BEM, which is free of singular integrals and corner problems. The numerical accuracy is also efficiently improved by this method.     

Some Discussion On the Calculation of the Discrete Fourier Transform(DFT)

In the field of signal analyies for time frequency, the DFT is a familiar term. Especially,when its efficient algorithm FFT given, the other operations in signal analyses are also usually translated to DFT as soon as possible so as to enhance the calculating speed. But in our exploning the virtual instrument for time frequency analyzing, two sorts of formulas to calculate DFT and its inverse transform (IDFT) are found. These results are in different value of operation from different signal analysts or from different instruments for time frequency analyzing, their physical meaning are also not clear enough.The period extent theory some previous document based on when defined DFT is firstly expatiated. Then, separately with future defining coefficient method and analogy evolvement method, the authors argue that, based on the period extent theory, it is more rational to calculate DFT with the formula given. A shortage is pointed out and corrected is appeared in some previous documents when having given the formula of DFT. The improper view is also clarified that the reason why there are two sorts of formulas is make by custom.The rationality of the authors view with three examples is visually verified in the end.     

Simulation of the penetration rate (ROP) of the air percussion drilling

It is difficult to calculate the penetration rate (ROP) of percussion drilling. In the early research, the empirical or semiempirical formulae of the ROP are derived from the laboratory or field data collected by the researchers. However, the ROP value of the formulae is not as accurate as that in the field. Benefiting from the dynamic model, the geometric structure model and the theory of the roller cone bit, the mathematical model of the hammer bit, the mathematical model of the true bottom hole and the mathematical model between the tooth and the rock of the hammer bit are established. Hence the ROP of the air percussion drilling can be predicted by simulation. Field tests show the models are reliable and the results are coincident with that in the field. The research can help to redesign the hammer bit and optimize the drilling parameters.     

栽培大豆(G.max)×半野生大豆(G.gracilis)后代主要农艺性状遗传参数的初步分析

本试验利用三个不同结荚习性的栽培大豆(G.max)做母本,分别与三个半野生大豆(G.graeilis)按NCⅡ设计配制的9个杂交组合,估测了F_1、F_2代主要农艺性状的优势指数;F_2代主要农艺性状的平均数、变幅、遗传变异系数、遗传力和预期遗传进度。试验结果表明:F_1代除百粒重、主茎有效节数以外,其余性状均有明显的杂种优势;F_2代除有效分枝、主茎粗以外,其余性状的优势指数均明显下降;F_2代遗传变异幅度大小的趋势为有限组合>亚有限组合>无限组合;生育日数、株高的遗传力高,可在早期世代进行选择;单株粒数、单株荚数、主茎粗的遗传力低,应在较晚世代选择;单株粒重及其主要构成因素均有较大的遗传进度绝对值,无限组合的遗传进度明显低于有限、亚有限组合。     

陆地棉族系(G.hirsutum race)引种研究初报

陆地棉族系(G.hirsutum race)原产于墨西哥南部、危地马拉、厄瓜多尔和萨尔瓦多等地;位于太平洋、加勒比海和墨西哥湾中间的高原地带,大约在北纬13°到22°之间的低纬度短日照地区。目前许多产棉国及棉花研究机构都在利     

从土壤中分离棉枯萎病菌(Fusarium oxysporum f.sp.vasinfetum (Atk) Synder & Hansen)选择性培养基研究

本文介绍一种用于分离检测土壤中棉枯萎病菌的选择性培养基—植选2号。其成分为:KH_2PO_41g,MgSO_4·7H_2O 0.5g,K_2S_2O_50.2g,KCl0.6g,NH_4NO_3 0.5g,蛋白胨5g,山梨糖10g,蔗糖5g,琼脂20g,蒸馏水1000ml,PCNB 620mg,Oxgall1g,硫酸链霉素300mg,盐酸金霉素75mg。根据棉枯萎病在此培养基上的形态特征,能较容易地识别和检测该病菌。     

普通小麦(T.aestivnm)陈旧种子遗传完整性(genetic iniegrity)变化的研究

本研究取材于青海省农林科学院自然库中保存30年及5年以上的普通小麦农家品种10个,测定了9项指标,结果表明:1957年贮入青海库的种子,1987年仍有一定的发芽能力,平均33%(5.56～46.0%),1981年贮入的种子平均发芽率为92.2%(84.3～98.0%)。发芽率与活力指数,鲜苗重、苗干重、电导率等均有一定相关关系,有的达极显著平准。陈旧种子根尖染色体后期异常染色体出现的频率高。但播种田间种植一年以后染色体恢复正常,异常率只1.18%,分析比较了不同贮存年代,不同发芽率的酯酶、过氧化物酶等同工酶,陈旧种子中条带数明显减少、削弱。对利用青海低温、干操自然库保存小麦种子提出了意见。     

长豇豆(V.sesquipedalis)SSR反应体系的建立

对长豇豆SSR反应中模板、引物、dNTP和酶的浓度进行了正交设计分析,结果表明,引物浓度对长豇豆SSR扩增影响明显,其它3种成分浓度没有显著影响,基因组差异亦对反应没有明显影响。通过进一步引物浓度实验并结合成本考虑,确定长豇豆SSR反应成分的最佳浓度为:模板1 ng/L、引物1.6μmol/L、dNTP各100μM/L、Taq聚合酶0.5 U。文中还对长豇豆SSR引物浓度对扩增效率的影响进行了讨论。本研究为利用SSR分子标记分析长豇豆遗传关系奠定了基础。