Construction of an RFLP map in sorghum and comparative mapping in maize

Abstract

An F2 population derived from a cross between Sorghum bicolor ssp. bicolor ('CK60') and Sorghum bicolor ssp. drummondii ('PI229828') was used to develop an RFLP genetic linkage map of sorghum. The map consists of 201 loci distributed among 10 linkage groups covering a map distance of 1530 cM, with an average 8 cM between adjacent loci. Maize genomic probes (52), maize cDNA probes (124), and sorghum genomic probes (10) were used to define the loci (55, 136, and 10, respectively). Ninety-five percent of the loci fit expected segregation ratios. The loci with distorted segregation ratios were confined almost exclusively to a region of one linkage group. Comparison of sorghum and maize maps indicated high correspondence between the two genomes in terms of loci order and genetic distance. Many loci linked in maize (45 of 55) were also linked in sorghum. Instances of both conserved and rearranged locus orders were detected.

Comparative Genomics of Plant Chromosomes

“…A surprising discovery based on its near-complete sequencing is that much of the Arabidopsis genome appears to be duplicated ( Figures 4A and 4B), supporting prior suggestions of segmental duplications (Kowalski et al, 1994;Paterson et al, 1996;Lan et al, 2000a) based on mapping restriction fragment length polymorphisms (RFLPs). Similar genetic mapping evidence of ancient duplication exists for sorghum (Chittenden et al, 1994;Pereira et al, 1994;Paterson et al, 1996) and rice (Kishimoto et al, 1994;Nagamura et al, 1995). An important question concerns the fate of genes after duplication.…”

“…Conservation across large chromosomal tracts, spanning ‫ف‬ 65 million years of evolution (Figure 2), is a recurring message from many investigations of diverse Poaceae (see Bennetzen and Freeling, 1993). Pioneering efforts in the comparative mapping of maize and sorghum (Hulbert et al, 1990) have been supported by more detailed studies (Whitkus et al, 1992;Berhan et al, 1993;Binelli et al, 1993;Chittenden et al, 1994;Pereira et al, 1994) and supplemented by the comparative organization of maize and rice , wheat and rice (Kurata et al, 1994), and maize, wheat, and rice . A host of investigations additionally encompasses many other cultivated Poaceae, with particular emphasis on the interrelationships among the homeologous chromosome sets of the Triticeae and their relatives (see Naranjo et al, 1987;Chao et al, 1989;Liu and Tsunewaki, 1991;Devos et al, 1992aDevos et al, , 1992bDevos et al, , 1993Devos et al, , 1995Liu et al, 1992;Xie et al, 1993;Namuth et al, 1994;Hohmann et al, 1995;Marino et al, 1996;Mickelson-Young et al, 1995;Nelson et al, 1995aNelson et al, , 1995bNelson et al, , 1995cVan Deynze et al, 1995).…”

Identification of quantitative trait loci associated with flowering, vegetative traits and photoperiod response in maize (Zea mays L)

“…QTL for PH in sorghum were located in the corresponding region of maize chromosomes 3,6, 8, and 9 where QTL for PH were identified herein Periera et al, 1994). A QTL for PH in rice also was identified in the corresponding region of maize chromosome 9 .…”

Plant genomics and agriculture: From model organisms to crops, the role of data mining for gene discovery

“…Sorghum genome mapping based on DNA markers began in 1990s, and since then several maps have been published. Data from available relevant published maps of sorghum (Whitkus et al 1992;Chittenden et al 1994;Pereira et al 1994;Ragab et al 1994;Xu et al 1994;Dufour et al 1997;Ming et al 1998;Nagamura et al 1998;Tao et al 1998;Boivin et al 1999;Peng et al 1999) were assembled and entered into a relational database (SQL7.0 TM ). This curated data contain detailed information on the source including the material used, linkage group, distance, marker designation and alias marker designation in cases where the markers have been renamed by others.…”