Track 4-1-4: Biotechnological Approaches to Improve Range, Pasture and Forage Species
Description
Buffel grass (Cenchrus ciliaris L.) is an important perennial grass grown widely in arid and semiarid regions of the world. It is one of the prominent species of the Dichanthium-Cenchrus-Lasiurus grass cover spread over the Peninsular India (Dabadghao and Shankarnarayan, 1973). C. ciliaris is a warm season, C4 grass well adapted to survive harsh conditions, elevated CO2 levels and wide range of climates and soil regimes. It is considered an excellent pasture grass as it provides highly nutritious and palatable forage during drought periods. Despite its excellent forage characteristics genetic improvement through conventional breeding methods has been difficult due to its apomictic mode of reproduction, and is mostly confined to the selection of elite lines from natural variants. (Bhat et al., 2001). Knowledge of genetic diversity and phenetic relationships among accessions is prerequisite for breeding programmes. The study of morphological variability is the only approach for assessing genetic diversity especially in minor crops. An assessment based only on agro-morphological traits might be biased because distinct morphotypes can result from spontaneous mutations. However, with molecular markers, genetic resources can accurately be assessed and characterized (Capo-chichi et al., 2004). Buffel grass has been extensively studied to understand the genetic regulation of apomixis targeting the genomic regions shared and conserved across grass family, while limited studies have been done so far to assess the genetic variation and utilization in breeding for agronomically important traits and absence of adequate genomic resources impeded further improvement. Cenchrus cultivars and accessions have previously been characterized using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), inter-simple sequence repeat (ISSR) and Sequence tagged site (STS) markers. While microsatellites are the most preferred markers due to their locus specificity, codominant nature, high polymorphism and reproducibility, their development and application is highly time consuming and expensive and has been limited to a few agriculturally important crops (Powell et al., 1996). An alternative way is to search the abundant sequence data already available in public databases to identify SSR’s. Nevertheless, markers developed in this way present a valuable resource for subsequent comparison between the model species and the related species. Therefore, the objectives of the present study were to develop EST based SSR markers and test their transferability potential in other related forage grasses.
Included in
Development of EST Derived Microsatellite Markers in Buffel Grass and Their Cross Transferability to Other Forage Grasses
Buffel grass (Cenchrus ciliaris L.) is an important perennial grass grown widely in arid and semiarid regions of the world. It is one of the prominent species of the Dichanthium-Cenchrus-Lasiurus grass cover spread over the Peninsular India (Dabadghao and Shankarnarayan, 1973). C. ciliaris is a warm season, C4 grass well adapted to survive harsh conditions, elevated CO2 levels and wide range of climates and soil regimes. It is considered an excellent pasture grass as it provides highly nutritious and palatable forage during drought periods. Despite its excellent forage characteristics genetic improvement through conventional breeding methods has been difficult due to its apomictic mode of reproduction, and is mostly confined to the selection of elite lines from natural variants. (Bhat et al., 2001). Knowledge of genetic diversity and phenetic relationships among accessions is prerequisite for breeding programmes. The study of morphological variability is the only approach for assessing genetic diversity especially in minor crops. An assessment based only on agro-morphological traits might be biased because distinct morphotypes can result from spontaneous mutations. However, with molecular markers, genetic resources can accurately be assessed and characterized (Capo-chichi et al., 2004). Buffel grass has been extensively studied to understand the genetic regulation of apomixis targeting the genomic regions shared and conserved across grass family, while limited studies have been done so far to assess the genetic variation and utilization in breeding for agronomically important traits and absence of adequate genomic resources impeded further improvement. Cenchrus cultivars and accessions have previously been characterized using random amplified polymorphic DNA (RAPD), amplified fragment length polymorphism (AFLP), inter-simple sequence repeat (ISSR) and Sequence tagged site (STS) markers. While microsatellites are the most preferred markers due to their locus specificity, codominant nature, high polymorphism and reproducibility, their development and application is highly time consuming and expensive and has been limited to a few agriculturally important crops (Powell et al., 1996). An alternative way is to search the abundant sequence data already available in public databases to identify SSR’s. Nevertheless, markers developed in this way present a valuable resource for subsequent comparison between the model species and the related species. Therefore, the objectives of the present study were to develop EST based SSR markers and test their transferability potential in other related forage grasses.
