A Preliminary Genetic Linkage Map of Soybean Using an Intraspecific Cross of Two Cultivars: 'Peking' and 'Lee'
Authors:
W. Yang1, D. B. Weaver1, B. L. Nielsen2 and J. Qiu3
Abstract:
A total of 64 EcoR I (+3) and Mse I (+3) primer combinations were used to generate amplified fragment length polymorphisms in a soybean (Glycine max L. Merr.) mapping population that consisted of 116 F2 plants from a cross between two cultivars: 'Peking' and 'Lee'. One hundred eleven amplified fragment length polymorphism markers were developed from 30 primer pairs. A molecular map consisting of 74 amplified fragment length polymorphisms, 2 simple sequence repeats, and one phenotypic trait (RcsPeking, resistance to Cercospora sojina), has been constructed. The map defined 599.8 cM of the soybean genome comprising 15 linkage groups. The average interval between these markers was 11.9 cM. An additional 37 polymorphic markers remained unlinked.
Genetic Variation in Wild Soybean (Glycine soja Sieb. & Zucc.) Populations Revealed with Simple Sequence Repeat Markers
Authors:
Yu Bin Li, Zhiang Hu (Author for Correspondence), Qin Zhang, Xin Deng, and Hong Xin Wang
Abstract:
Microsatellites or simple sequence repeats (SSRs) consist of tandemly repeated core sequences that often vary in repeat number and are flanked by conserved DNA sequences. (Maughan et al 1995). It is well-known that SSRs are ideal genetic markers in that they are (1) highly abundant and evenly distributed (2) highly polymorphic (3) codominant (4) rapidly typed via PCR and (5) very accessible to other laboratories via published primer sequences (Weber 1990; Saghai-Maroof et al 1994). The length polymorphisms of SSRs in soybean and wild soybean (Glycine soja) have been widely studied (Akkaya et al 1992; Jiang et al 1995; Akkaya et al 1995; Maughan et al 1995 and Powell et al 1996). However to our knowledge SSRs DNA marker has not yet been served as a genetic marker in the natural populations of wild soybean (Glycine soja Sieb. & Zucc.). The salt tolerance efficiencies of wild soybean individuals were evaluated by using the method in our previous work (Hu and Wang 1997; Wang et al. 1997) and several RAPD markers were found to be linked to the salt tolerance character of wild soybean (Zhang et al. 1999). In present paper we evaluated the applicability of SSRs as a source of genetic markers in salt resistance of wild soybean in two natural populations in saline conditions.
Further Study on Genotypic Variation of Salt Tolerance to Wild Soybean (Glycine soja Sieb. & Zucc.)
Authors:
Yu Bin Li, Zhi Ang Hu (Author for Correspondence) and Hong Xin Wang
Abstract:
Soil salinity has a major impact on plant growth and affects about 6% of the total global land area (Flowers and Yeo 1995). The development of salt tolerant crops including soybean could greatly help to meet demands on the food supply. The wild perennial Glycine species have been suggested as a potential source of germplasm to improve soybean for agronomic traits including salt tolerance (Brown et al 1984;Pantalone & Kenworthy 1989). It is well known that the annual wild soybean Glycine soja Sieb. & Zucc. is the unique close relative of cultivated soybean and has been effectively used in soybean breeding. Hu and Wang (1997) first reported the variation of salt tolerance of each plant in natural populations of Glycine soja by using a new method for evaluating salt tolerance efficiencies (STEs) of individual plants based on the timing of the leaf injury. In their experiments however continuous illumination and a constant temperature(21oC) were maintained and only the seedlings were tested. The present work further evaluates the salt tolerance of wild soybean in two saline populations under different temperature schedules and developmental stages in order to elucidate salt tolerance of Glycine Soja in the real and natural situation.
Genetic Analysis of a Root Fluorescence Mutant from Yunnan Province China
Authors:
Pinar Cubukcu1, Soon-Suk Kang2, and Reid G. Palmer2
Abstract:
Fluorescence of soybean roots under ultraviolet light was used in Europe to distinguish cultivars (Chmelar 1934; Chmelar and Mostovoj 1934). Delannay and Palmer (1982) and Sawada and Palmer (1987) identified four recessive loci fr1 fr2 fr4 and fr5 and one dominant locus Fr3 that condition nonfluorescent roots in soybean.
Changes of Proline Levels and Abscisic Acid Content in Tolerant/Sensitive Cultivars of Soybean under Osmotic Conditions
Authors:
Zheng Yi-Zhi and Li Tian
Abstract:
In responses to drought and salinity stresses many plant species including soybean accumulated high levels of proline (Pro) which is thought to function in stress adaptation [1]. Also abscisic acid (ABA) plays an important role in the responses of plants to drought stress. It appears that drought stress triggers the production of endogenous ABA which in turn induced the transcription of several genes. These genes are also thought to function in the protection of cells from dehydration [2]. Here changes of free proline levels and endogenous ABA content in seedling leaves of different soybean cultivars were detected showing a correlation of biotypes having elevated levels of proline and ABA content with enhanced tolerance to PEG stress.
Cloning and Characterization of a Molecular Marker Associrance from Soybean Cultivarsated with Salt Tole
Authors:
Zhang Qin, Yun Rui, Hu Zhiang, Zhong Min, Deng Xin
Abstract:
Much progress has been made towards elucidating the underlying mechanisms controlling salt tolerance in plant (M. R. Foolad et al., 1997; H. Pakniyat et al., 1997). These studies led to the analysis and isolation of genes that encode proteins related to salt tolerance. In previous study, we applied DAF (DNA Amplification Fingerprinting) to screen two salt-tolerant soybean cultivars (Morgan and Wenfeng No.7) and two salt-sensitive ones (Hark and Jackson) and found three polymorphic markers (8.6f/350bp, 8-27/240bp and 8-15/215bp) which only appeared in salt-tolerant cultivars (Zhong et al., 1997). In the present work, we describe the cloning and characterization of the specific marker 8-27/240bp in order to further study whether it plays an important role in salt tolerance of soybean.
Gene Expression of Soybean Calli Culture Affected by Auxinoids with Various Chemical Structure
Authors:
Elena Hlinkov' and Claudia Ruzickov'
Abstract:
Haberlandt's hypothesis (Haberlandt 1902) about totipotency of living plant cells meant a shift from a level of the hypothesis into a reality in the beginning of 60's when cultivation media for somatic cells of tobacco and carrot were prepared (Skoog et Miller 1957). Callus induction can be induced practically on all plant explants. Differences in a rate of cell conversion into a dedifferentiation are conditioned with the chemical structure of used exogenous growth regulators an ontogenetic stage of explant and concentration gradient between exogenous and endogenous growth regulators...
Variations for Biomass, Economic Yield and Harvest Index among Soybean Cultivars of Maturity Groups III and IV in Argentina
Authors:
M.E. Weilenmann de Tau (etau@balcarce.inta.gov.ar) and J. Lüquez
Abstract:
In the southern pampeana region of Argentine, south of the parallel 36° Latitude S, soybean (Glycine max (L.) Merr.) crop is grown on approximately 200.000 hectares with further expansion expected. Cultivars of maturity Groups III and IV are well adapted to this zone. Identify plant traits that contribute to crop productivity is essential for developing high yielding cultivars (Salman and Brinkman, 1992). Harvest index (HI), defined as ratio between economic yield (EY) and the total biomass i.e biological yield (BY), influences EY more than any other yield determining plant trait (Bhardwaj and Bhagsari, 1989). Donald and Hamblin (1976) have reviewed the history of the concept of HI and concluded that it may be used as a criterion for yield evaluations. Soybean economic yield was reported to be correlated with HI (Bhardwaj and Bhagsari, 1989). Cultivars with high HI should be combined with cultivars having high biomass to increase yield (McVetty and Evans, 1980). The values of HI in soybean (Glycine max (L.) Merrill) range between 0.47 and 0.56, with absence of water stress (Hume et al.,1989). Twenty-one soybean genotypes of maturity group IV and six of maturity group III were evaluated under two different conditions of humidity with the following objectives: a) determine variability for EY, BY and HI among soybean cultivars, b) identify genotypes having high BY, EY and HI and c) determine the associations between BY and HI with EY in order to enhance soybean grain yields combining superior genotypes for BY and HI.
Inheritance of Genes Controlling Photoperiod Insensitivity and Flowering Time in Soybean
Authors:
I. M. Tasma1, L. L. Lorenzen2, D. E. Green1, and R. C. Shoemaker1,3
Abstract:
The objective of this research was to study the inheritance of genes controlling photoperiod insensitivity and flowering time in soybean. Two single-cross populations, IX132 (PI 317.336 X 'Corsoy'), and IX136 (PI 317.334B X 'Corsoy') were developed for this purpose. The populations were inbred to obtain 101 and 100 F6:7 lines, respectively, using a modified single seed descent. Flowering time (days to R1) of the RI lines from each population was observed in the growth chamber at 12 h and 20 h photoperiods using fluorescent and incandescent lamps. Results show that the RI lines have dramatically different responses to day length. A normal distribution of flowering times was observed when the lines were grown in growth chamber with 12 h photoperiod. When the lines were grown in growth chamber with 20 h photoperiod, however, a discontinuous distribution was observed. This suggested that the insensitivity of the RI lines on long day length may be controlled by few major genes. The time of flowering was delayed in almost all lines when grown in growth chamber with 20 h photoperiod compared to those grown in the growth chamber with 12 h photoperiod. The flowering delays were 5 to 75 days in population IX132 and 0 to 75 days in population IX136. Chi-square tests show that the segregation data fit a 1:6:1 ratio in population IX132 and IX136. Based on these tests a minimum of three genes are proposed to control photoperiod insensitivity in both populations.
Integrated physical mapping of the soybean genome: A tool for rapid identification of economically important genes.
Authors:
Kimbely Zobrist 1, Khalid Meksem 1, Chengcang Wu 2, Quanzhou Tao2, Hongbin Zhang 2, David A. Lightfoot 1
Abstract:
Investment in crop genomic science is justified by the existence of genus, species and cultivar specific genes with no known function. A subgroup, within this group of genes, is expected to be genes of agronomic and economic importance such as disease resistance genes, major yield determinates and genes that produce specific chemicals and components. Identification of members of the economically important gene subgroup has been painstakingly slow by conventional genetics and preliminary genomics. A microsattelite marker map, with about 600 mapped markers, is available in soybean. This anchored genetic map has been integrated with RFLP, RAPD, and AFLP marker maps (Shoemaker and Specht 1995; Mansur et al. 1996; Keim et al., 1996; Chang et al., 1997 Cregan et al., 1999). About 300 QTL conditioning traits of agronomic importance have been identified by about 15 groups over the last 10 years (Imsande et al., 1998; Soybase http://probe.nalusda.gov:8300). However, it is not feasible to fine-map and isolate large numbers of soybean genes by this technology.
Construction and Characterization of a BAC Library for the Soybean Cultivar A3244
Authors:
J.P. Tomkins, D.A. Frisch, J.R. Byrum and R.A.. Wing
Abstract:
The construction of a physical framework for the soybean genome requires the use of large insert genomic libraries. The bacterial artificial chromosome (BAC) cloning system appears to offer advantages over other large insert cloning systems as discussed previously (Shizuya et al., 1992; Woo et al., 1994). Therefore, the BAC system is very appealing as a vehicle for advanced genome analysis in soybean. At the present time, the construction of three soybean BAC libraries has been reported in the literature (Marek and Shoemaker, 1997; Danesh et al., 1998; Tomkins et al., 1999). Estimated coverage for these libraries range between 3 and 9 haploid genome equivalents. In order to develop a comprehensive physical framework for soybean using fingerprinting (Marra et al, 1997) and BAC end sequencing technologies, a deeper coverage BAC library providing at least 10 genome equivalents will be required. Our objective was to develop a deep coverage soybean BAC library for the purpose of creating a comprehensive physical framework of the soybean genome.
Agronomic traits correlative analysis between interspecific and intraspecific soybean crosses
Authors:
Qi Yang & Jinling Wang
Abstract:
Two semicultivated (G.gracilis) and four cultivated (G.max) cultivars were used to make 15 crosses and the resulting F1 and F2 progenies were evaluated for morphological yield and quality characters. The relationship among agronomic characters between intraspecific and interspecific soybean crosses was analyzed. The objective of this study was to compare the difference among agronomic characters between intraspecific and interspecific soybean crosses. Plants derived from crosses involving G.gracilis were taller more vigorous had greater seed and pod number /plant lower seed-stem ratio and smaller 100-seed weight than those from intraspecific crosses. In interspecific crosses taller and more vigorous plants had close association with lower seed-stem ratio. The correlations of 100-seeds weight with the duration of developing stage were in the opposite direction to those with seed and pod number/plant. The correlation of protein content with developing stage were in the opposite direction to that of oil content. It is suggested that it was difficulty to select plants both higher in protein and in oil content derived from interspecific crosses.
Field Resistance to Sudden Death Syndrome is effective at low Inoculum Concentration in Greenhouse Assays
Authors:
V.N. Njiti, J.E. Johnson, G.A. Torto and D.A. Lightfoot.
Abstract:
Effective selection of field resistance to soybean (Glycine max (L.) merr.) sudden death syndrome (SDS) measured by leaf scorch requires multiple environments. Current greenhouse assays reduce GxE but fail to predict field resistance. Our objective was to develop a greenhouse assay with a low GxE that improved selection of field resistance to SDS among soybeans. Recombinant inbred lines were evaluated for scorch severity (DS) at three inoculum rates in two experiments and for root infection at one inoculum rate in one experiment. Cultivars were compared using DS from one experiment at one inoculum rate. The heritability of DS among recombinant inbred lines in the greenhouse was 63% at the low 35% at the moderate and 34% at the high inoculum rates. Reduced inoculum rates in the greenhouse (<5000 spores cm3 of soil) provided DS values that significantly correlated with field leaf scorch. The number of lines potentially resistant to SDS within a segregating population could be reduced by 57% using a F. solani inoculum rates of 3,500 - 5,000 spores per cm3 of soil and greenhouse DS <1.9 for selection. About 10% of field resistant lines were eliminated by error. Among unrelated soybean cultivars the low inoculum rate separated genotypes (P <0.05) and their greenhouse DS significantly correlated with field DS (r =0.9) and disease index (r =0.86). Therefore the method is an effective tool for inheritance studies and cultivar trials.
Inheritance of a five leaflet character arising from wild soybean (Glycine soja Sieb. et Zucc.) in soybeans (G. max (L.) Merr.)
Authors:
Wang Ke-Jing wangkejing@ihw.com.cn, Li Fu-Shan, Zhou Tao and Xu Zhan-You
Abstract:
The inheritance of a five leaflet mutation of soybeans originally inherited from the wild was studied using cross analysis. Six crosses were made between Five Leaf Bean with the five leaflet trait and other 6 lines of normal leaves. F2 plants of 5 crosses produced major three five leaflet leaves and also some minor four six and seven multifoliolate leaves. There were two kinds of segregation ratios for major five leaflet (including other multifoliolate leaves) and trifoliolate characters in the F2 progeny plants. Five crosses showed a goodness of fit to a 3 : 1 ratio and one cross showed a satisfactory 63 : 1 ratio. The cross analysis indicated that besides the Lf1 gene controlling the five leaflet trait other two newly found genes could also control this trait. These three genes were independently genetic incompletely dominant and effect-duplicated. The results also suggested that the Five Leaf Bean a donor of five leaflet genes acquired by random selection to a cross progenies ((cultivar1 x wild soybean) x cultivar2) had heterogeneous genotypes at the three loci among individuals.