DNA‐Based Markers for a Recessive Gene Conferring Anthracnose Resistance in Sorghum

Abstract

Resistance to anthracnose in sorghum [Sorghum bicolor (L.) Moench] accession SC326‐6 was found to segregate as a simple recessive trait in a cross to the susceptible cultivar BTx623.F3 progeny tests following self pollination of 115 F2 individuals identified homozygous resistant and susceptible F2 plants for use in bulked‐segregant analysis. DNA from the parental cultivars and the bulks was screened by PCR amplification with 300 RAPD (random amplified polymorphic DNA) primers. Two RAPD primers amplified a sequence that co‐segregated with the recessive resistance allele, while another amplified a band linked to the susceptible allele.

Evaluation of resistance in sorghum genotypes to the causal agent of anthracnose

“…Resistance to isolate 1 was mainly due to dominant alleles that confered vertical resistance but also by incomplete dominance alleles (hybrids 121, 122, 133, 134 and 138) and recessive alleles (hybrids 98 and 112), by comparing the genitors and hybrids infection scores to those that present both information.. In many cases, alleles that confered resistance to isolate 11 (Jataí) were recessive (hybrids 95, 98, 99, 103, 104, 106, 108, 110, 113, 118, 119, 121, 122, 134 and 150), which is in accordance with studies done by Boora et al (1998), Mehta et al (2005) and Singh et al (2006). Hybrid 93 was the only three-way hybrid tested.…”

Evaluation of Ethiopian sorghum accessions for resistance against Colletotrichum sublineolum

“…This was confirmed by Erpelding (2007), who reported a single dominant gene conferring resistance to the foliar phase of anthracnose in sorghum cultivar Redlan. Tenkouano (1993), quoted by Perumal et al (2009), revealed a single genetic locus with multiple allelic forms conferring resistance to anthracnose in SC326-6 while Boora et al (1998) revealed that resistance to anthracnose in SC326-6a is encoded by single recessive gene. This suggested the need to look for additional sources of resistance in order to identify more genes that code for anthracnose resistance.…”

Sorghum [Sorghum bicolor (L.) Moench] breeding for resistance to leaf and stalk anthracnose, Colletotrichum sublineolum, and improved yield: Progress and prospects

“…There is evidence that resistance to the anthracnose stages to leaf and stalk rot is under independent genetic control (Casela et al, 1997). LeBeau and Coleman (1950) verified that the resistance is controlled by recessive genes, which was confirmed by the studies by Singh et al (2006) and Boora et al (1998) using RAPD and SCAR markers for sorghum lineages. In other studies, the inheritance of resistance was reported to be determined by a larger number of genes with partial dominance or an additive effect; by a dominant gene without cytoplasmic influences; or by a single locus with multiple alleles (Murty and Thomas, 1989;Tenkouano and Miller, 1993).…”

“…Tenkuano et al (1993a,b) proposed selection at the seedling stage based on phytoalexin content. Recently, markers linked to anthracnose resistance have been identified (Boora et al, 1998). The molecular markers make the pyramiding of genes feasible and the genes be more stable across environments.…”

“…Hybrid seed parents such as ICSA/B 260 and ICSA/B 295 were also found to be tolerant to anthracnose (Reddy et al, 2007). Boora et al (1998) identified markers linked to a recessive gene conditioning anthracnose resistance. Panday et al (2002) used bulk segregant analysis to identify two RAPD markers linked to anthracnose resistance in sorghum accession SC326-6 and found to segregate as simple recessive trait when crossed with BTx623, a susceptible cultivar.…”