Genetic base of Indian potato selections as revealed by pedigree analysis

In the present study an attempt has been made to determine the genetic base of 138 Indian chickpea varieties through pedigree analysis. The genetic base of 138 varieties can be traced to 160 ancestors utilised to bring genes in development of varieties. Among these, 118 ancestors were used only once or twice. The most frequently used parent included Rabat (37), Pb 7 (36), IP 58 (32), C 1234 (32) and S 26 (27). Rabat and Pb7 are present in the pedigree of more than 26% of varieties followed by C 1234 (23.29%), IP 58 (23.29%) and S 26 (19.57%). Most of the frequently used parents have been used indirectly in the crossing programme. Only 28 parents could represent 50% of total genetic base of chickpea varieties developed in the country. Although conscious efforts have been made to include diverse parents in the chickpea breeding leading to broad genetic base of the varieties yet a huge arsenal of germplasm lines remains unutilised or not resulted in varieties. There is a need to utilise the germplasm resources as well as modern techniques of breeding to incorporate multiple biotic and abiotic stress resistance for yield improvement and stabilization as well as improvement in market driven traits like extra-large seed sized kabuli lines. The present article describes the results of pedigree analyses to determine the genetic base of the released cultivars, reasons for narrow genetic base and possible approaches and strategies for its widening in chickpea.

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Genetic base and relatedness of Indian early maturing potato (Solanum tuberosum) selections

The Journal of Agricultural Science ◽

10.1017/s0021859610000705 ◽

2010 ◽

Vol 149 (2) ◽

pp. 217-225

Author(s):

R. KUMAR ◽

G. S. KANG ◽

S. K. PANDEY ◽

J. GOPAL

Keyword(s):

Genetic Diversity ◽

Genetic Background ◽

Common Ancestor ◽

Pedigree Analysis ◽

Specific Gene ◽

Genetic Base ◽

Early Maturing ◽

Gene Complexes ◽

Almost All ◽

Selection Of

SUMMARYPedigree analysis was used to study the genetic background of 66 Indian early maturing potato selections, the pedigree of which was traced back to 35 ancestors. Six of the 35 contributed 0·42 of the genetic base, which shows the narrow genetic base of Indian early maturing genotypes. Genotypes 2814 (a)1 (f=0·145) and 3069 (d)4 (f=0·145) were the ancestors which appeared most frequently. Based on the coefficient of relationship, the 66 selections were grouped into seven groups with one common ancestor in almost all the selections within a group. The genotypes Kufri Ashoka, Kufri Pukhraj, AGB-69-1, Kufri Jyoti, Kufri Alankar, Kufri Lauvkar and Kufri Kuber were identified as very important parents/ancestors, carrying specific gene complexes valuable in new selections. Crosses between selections from different diversity groups can result in the selection of useful clones while increasing or maintaining genetic diversity, which is desirable to ensure sustainable breeding progress in the future.

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Pedigrees and genetic base of flax cultivars registered in Canada

Canadian Journal of Plant Science ◽

10.1139/cjps-2015-0337 ◽

2016 ◽

Vol 96 (5) ◽

pp. 837-852 ◽

Cited By ~ 9

Author(s):

Frank M. You ◽

Scott D. Duguid ◽

Irene Lam ◽

Sylvie Cloutier ◽

Khalid Y. Rashid ◽

...

Keyword(s):

Gene Pool ◽

Dominant Role ◽

Core Gene ◽

Pedigree Analysis ◽

Oilseed Crop ◽

Pedigree Data ◽

Coefficient Of Parentage ◽

Breeding Programs ◽

Genetic Base ◽

Foreign Countries

Flax is an important oilseed crop with industrial, animal, and human nutrition uses. Breeding programs for linseed and fibre flax were initiated in Canada in the early 1900s. A total of 82 flax cultivars have been registered in Canada since 1910, including 24 cultivars introduced from foreign countries and 58 cultivars developed by Canadian breeders. This study collated pedigree data of Canadian flax cultivars and quantified their genetic base via pedigree analysis and coefficient of parentage (CP). A fairly high mean CP of 0.14 was observed between all registered cultivars; this value was even higher (0.23) when only the 46 cultivars released from 1981–2015 were considered. The registered cultivars traced back to 46 ancestors; 72% originated from foreign countries and contributed 83% of the genetic base of all cultivars, illustrating the dominant role played by foreign germplasm in the genetic improvement of Canadian flax. The top 11 ancestors contributed 70%–93% of the genetic base of modern flax cultivars released in the last three decades and formed the core gene pool of Canadian flax cultivars. The genetic base of Canadian cultivars is relatively narrow, although it has gradually expanded, especially in the last two decades. Broadening the genetic base through the introduction of new exotic germplasm is needed to invigorate the gene pool of Canadian flax breeding programs.

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Radiographic Prevalence of Osteochondrosis in Yearling Feral Horses

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.1055/s-0038-1632481 ◽

1999 ◽

Vol 12 (03) ◽

pp. 151-155 ◽

Cited By ~ 19

Author(s):

L. W. Valentino ◽

E. M. Gaughan ◽

D. R. Biller ◽

R. H. Raub ◽

J. D. Lillich

Keyword(s):

Subchondral Bone ◽

Management Practices ◽

Articular Surface ◽

Radiographic Images ◽

Feral Horses ◽

Metacarpophalangeal Joints ◽

Genetic Base ◽

Domestic Horses ◽

The Difference ◽

Metatarsophalangeal Joints

The purpose of the study is to document the prevalence of articular surface osteochondrosis lesions in feral horses. Eighty yearling feral horses were used. Radiographic images of the left stifle, both tarsocrural, metatarsophalangeal, metacarpophalangeal joints were taken. Radiographs were examined for the presence of osteochondral fragmentation and abnormal outline of subchondral bone suggestive of osteochondrosis. The prevalence of each lesion was calculated for each joint as well as for overall prevalence within the group, the latter being 6.25%. Typical osteochondrosis lesions were found within the tarsocrural and metatarsophalangeal joints. Based on the difference in prevalence of osteochondrosis between feral and certain domestic horses, management practices and perhaps genetic base may have a greater influence on the development of the disease in horses than trauma alone.

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Pedigree Analysis of Constitutional Delay of Growth and Maturation: Determination of Familial Aggregation and Inheritance Patterns

The Journal of Clinical Endocrinology & Metabolism ◽

10.1210/jc.2002-020862 ◽

2002 ◽

Vol 87 (12) ◽

pp. 5581-5586 ◽

Cited By ~ 89

Author(s):

Ines L. Sedlmeyer ◽

Joel N. Hirschhorn ◽

Mark R. Palmert

Keyword(s):

Familial Aggregation ◽

Pedigree Analysis ◽

Inheritance Patterns ◽

Constitutional Delay

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Comparative analysis of genetic background in eight near-isogenic wheat lines with different H genes conferring resistance to Hessian fly

Genome ◽

10.1139/g10-095 ◽

2011 ◽

Vol 54 (1) ◽

pp. 81-89 ◽

Cited By ~ 8

Author(s):

S. S. Xu ◽

C. G. Chu ◽

M. O. Harris ◽

C. E. Williams

Keyword(s):

Genetic Background ◽

Genetic Similarity ◽

Triticum Aestivum L ◽

Hessian Fly ◽

Pedigree Analysis ◽

Recurrent Parent ◽

Linkage Drag ◽

Near Isogenic Lines ◽

Isogenic Lines ◽

H Gene

Near-isogenic lines (NILs) are useful for plant genetic and genomic studies. However, the strength of conclusions from such studies depends on the similarity of the NILs’ genetic backgrounds. In this study, we investigated the genetic similarity for a set of NILs developed in the 1990s to study gene-for-gene interactions between wheat ( Triticum aestivum L.) and the Hessian fly ( Mayetiola destructor (Say)), an important pest of wheat. Each of the eight NILs carries a single H resistance gene and was created by successive backcrossing for two to six generations to susceptible T. aestivum ‘Newton’. We generated 256 target region amplification polymorphism (TRAP) markers and used them to calculate genetic similarity, expressed by the Nei and Li (NL) coefficient. Six of the NILs (H3, H5, H6, H9, H11, and H13) had the highly uniform genetic background of Newton, with NL coefficients from 0.97 to 0.99. However, genotypes with H10 or H12 were less similar to Newton, with NL coefficients of 0.86 and 0.93, respectively. Cluster analysis based on NL coefficients and pedigree analysis showed that the genetic similarity between each of the NILs and Newton was affected by both the number of backcrosses and the genetic similarity between Newton and the H gene donors. We thus generated an equation to predict the number of required backcrosses, given varying similarity of donor and recurrent parent. We also investigated whether the genetic residues of the donor parents that remained in the NILs were related to linkage drag. By using a complete set of ‘Chinese Spring’ nullisomic-tetrasomic lines, one third of the TRAP markers that showed polymorphism between the NILs and Newton were assigned to a specific chromosome. All of the assigned markers were located on chromosomes other than the chromosome carrying the H gene, suggesting that the genetic residues detected in this study were not due to linkage drag. Results will aid in the development and use of near-isogenic lines for studies of the functional genomics of wheat.

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