Genetic Linkage Between Isozyme, Morphological, and DNA Markers in Tepary Bean

A genetic map of tepary bean (Phaseolus acutitolius A. Gray) may be useful to plant breeders attempting to transfer desirable genes from this species to other Phaseolus species. In order to expand the genetic information available for tepary bean, the inheritance of and linkage relationships among 23 morphological, isozyme, and RFLP markers were determined. All but one of the characters segregated in a monogenic fashion, and low levels of segregation distortion were observed. New two-locus linkages Identified included Aat-2/Gpi-c2, Aco-2/Dia-3, and Dia-3/ldh-x. Nine of the 23 loci exhibited linkage to other loci analyzed and could be assigned to one of three district linkage groups. Two tepary bean linkage groups (Adh-1/Aat-2, Aco-2/Dia-3) appear to be conserved in common bean, although the linkage estimates for Adh-1Aat-2 are dramatically different in these species. The Adh-1/Aat-2 linkage also appears to be conserved in lentil and pea. Additionally, the Gpi-c1/Pgd-3 linkage has a possible counterpart in soybean, and the Fdh-1/Gpi-c1 linkage in tepary bean is maintained In chickpe

A Marker Locus, Adh-1, for Resistance to Pea Enation Mosaic Virus in Pisum sativum

Linkage between Adh-1, the locus specifying the more anoda) isozyme of alcohol dehydrogenase, and En, the locus controlling resistance to pea enation mosaic virus, was investigated in the garden pea, Pisum sativum L. A recombination frequency of 4% was observed between the two loci, indicating that Adh-1 may be a practical marker for En. The use of Adh-1 in combination with other loci as brackets around En, thereby increasing the reliability of an indirect screen, is also discusse

Investigations of an urban area and its locale using ERTS-1 data supported by U-photography

An urban area in central Pennsylvania and the surrounding locality were investigated separately at first by photointerpretation of ERTS-1 imagery and by computer processing of MSS tapes. Next the photointerpretation and processing were coordinated. The results of the cooperative effort of photointerpreters and computer processing analysts were much improved over independent efforts. It was found that single frames of U-2 photography could be projected onto printer output maps with little recognizable distortion in areas 10 to 25 cm square. In this way targets could be identified for use as training areas for computer processed signature identification. In addition, at any stage of category mapping, the level of success in correct classification could be assessed by this method. The results of the classification of the study area are discussed

Chromosomal locations of twelve isozyme loci in Pisum sativum

Approximate chromosomal locations of 12 loci specifying electrophoretic enzyme variants are described in the garden pea (Pisum sativum L.). The enzyme loci are distributed on five of the seven chromosomes. The position of the loci on chromosomes 2 and 3 are such that most of the known markers on these chromosomes will exhibit linkage with at least one of the isozyme loci. Several of the loci studied code for enzymes that have isozymic counterparts in other compartments of the cell. In order to distinguish among the genes coding these isozymes we have added a suffix to the locus designation corresponding to the intracellular location of its produc

Further genetic analysis and linkage relationships of isozyme loci in the pea: Confirmation of the diploid nature of the genome

Allozyme polymorphism is described and the mode of inheritance determined for 15 loci in Pisum sativum. The approximate position on the pea linkage map is described for 12 of these loci. The remaining three loci formed a single group that assorted independently of morphological markers on each of the seven currently recognized linkage groups. Possible cases of gene duplication are identified in the alcohol dehydrogenase and esterase enzyme systems, but in neither case was polyploidy a likely explanation for the paired loci. Nor did the arrangement of the isozyme loci on the linkage map give any indication that the pea genome is of polyploid derivation. We conclude that the "polymeric” genes that have been described in the pea are probably not homologous pairs and do not reflect a polypiold ancestr

The Penn State ORSER system for processing and analyzing ERTS and other MSS data

The author has identified the following significant results. The office for Remote Sensing of Earth Resources (ORSER) of the Space Science and Engineering Laboratory at the Pennsylvania State University has developed an extensive operational system for processing and analyzing ERTS-1 and similar multispectral data. The ORSER system was developed for use by a wide variety of researchers working in remote sensing. Both photointerpretive techniques and automatic computer processing methods have been developed and used, separately and in a combined approach. A remote Job Entry system permits use of an IBM 370/168 computer from any compatible remote terminal, including equipment tied in by long distance telephone connections. An elementary cost analysis has been prepared for the processing of ERTS data

Extensive Conservation of Linkage Relationships Between Pea and Lentil Genetic Maps

A 560-cM linkage map consisting of 64 morphological, isozyme, and DNA markers, has been developed from an interspecific cross (Lens ervoides × L. Culinaris). In addition, nine markers were scored that assorted independently of any of the multilocus linkage groups. Comparison of this map with that established previously for Pisum sativum reveals eight regions in which linkages among marker loci appear to have been conserved since the divergence of the two genera. These conserved linkage groups constitute at least 250 cM, or approximately 40% of the known linkage map for Lens. The two genera represent disparate lineages within the legume tribe Vicease, indicating that all members of this tribe may possess linkage groups similar to those identified in Lens and Pisum. Instances where the Pisum and Lens maps differed included the regions surrounding the 45S ribosomal tandem repeats and the position and distribution of the genes encoding the small subunit of ribulose bisphosphate carboxylase. We also found a highly repeated sequence unique to Lens that maps within a linkage group shared between the two genera and a cDNA sequence that displays significant variation in copy number within the genus Len

Inheritance and Linkage Relationships of Morphological and Isozyme Loci in Lentil (Lens Miller)

Allozyme polymorphisms for 18 loci are described and their monogenic inheritance is demonstrated. We investigated linkage relationships among the 18 isozyme loci as well as four genes controlling morphological traits. Six small linkage groups were identified, containing 14 of the loci analyzed. Several of these groups appear to be conserved between Lens and Pisum, indicating that this intergeneric comparison may expedite genetic studies and breeding programs in both crop

An isozyme marker for resistance to bean yellow mosaic virus in Pisum sativum

Linkage between Pgm-p, the locus specifying the plastid specific phosphoglucomutase, and Mo, the locus controlling resistance to bean yellow mosaic virus (BYMV), was investigated in the garden pea, Pisum sativum L. Both genes are known to be on chromosome 2 and exhibit linkage with two morphological marker loci, K and Wb. Our results indicate that the gene order is: Wb—K—Pgm-p—Mo. A map distance of approximately two recombinant units was determined for the Pgm-p—Mo linkage, suggesting that the enzyme locus can be used as a genetic marker for resistance to BYM