Inheritance of resistance to anthracnose (Colletotrichum capsici) at seedling and fruiting stages in chili pepper (Capsicum spp.)

Abstract

Inheritance of resistance to anthracnose at fruiting and seedling stages was studied in two F 2 populations from a cross between Capsicum annuum cv. ÔBangchangÕ and Capsicum chinense ÔPBC932Õ. The first F 2 was used to study anthracnose resistance at fruiting stage on mature green and ripe red fruit, and the second F 2 was used to study the resistance at both seedling and fruiting stages. Fruit inoculation was performed on detached fruit using a microinjector. Disease severity was assessed on a 0-9 scale at 7 days after inoculation. Seedling inoculation was performed using a drop method on detached leaves of 4-week-old seedlings. Disease severity was assessed on a 1-9 scale at 3 days after inoculation. The distribution of the disease scores of green and red fruit, and seedlings in both F 2 populations suggested a single gene model for each trait. Three different recessive genes were responsible for the three resistances from this cross. Linkage analysis suggested that the resistances at green and red fruit were linked (recombination frequency 0.25), and that the seedling resistance was not linked to the fruit resistances.

Resistance in Capsicum spp. to anthracnose affected by different stages of fruit development during pre- and post-harvest

“…Some Colletotrichum isolates were pathogenic to unripe fruit of resistant genotypes 'PBC932' (C. chinense), 'PBC80' and 'PBC81' (C. baccatum), but they were not pathogenic to red fruit of those genotypes, which suggests that different resistance genes are expressed at different stages of fruit maturity (Taylor et al, 2007). A similar result was observed by Mahasuk et al (2009a), who studied the inheritance of resistance to C. capsici at different stages of fruit ripening (unripe and ripe) from crosses between Capsicum annuum (susceptible) and Capsicum chinense (resistant). They verified the involvement of two different genes responsible for resistance in ripe and unripe fruit, suggesting that the change in fruit maturation may have triggered the expression of different genes at different stages.…”

“…Kanchana-Udomkan et al (2004) found that fruit size does not affect the development of the disease, and unripe fruit of C. chinense were more susceptible to anthracnose caused by C. gloeosporioides than ripe fruit. Pakdeevaraporn et al (2005) and Mahasuk et al (2009a) showed that different genes control resistance to anthracnose in unripe and ripe fruit, which is extremely significant for Capsicum breeding seeking resistance to anthracnose. Mongkolporn et al (2010) also observed different reactions caused by the stage of development of Capsicum spp.…”

“…Park et al (2009) suggested that C. baccatum has higher levels of resistance to anthracnose than other species of Capsicum, and that this species is an important source of genetic resources for resistance to anthracnose. However, according to Mahasuk et al (2009a), resistant accessions of C. chinense are most commonly used in breeding programs aiming at resistance to anthracnose because this species belongs to the same gene pool as C. annuum, which indicates a greater chance of success in the transfer of resistance genes among species. However, successful crosses were carried out between C. annuum and C. baccatum to transfer the gene Bs7, which confers resistance to bacterial spot in sweet pepper (Potnis et al, 2012), demonstrating that gene transfer between these two species is possible.…”

Research Article Multiple genetic resistances in Capsicum spp.

“…Since then, several researchers have used these genotypes in Capsicum breeding programs for resistance to anthracnose. As examples, we may cite studies developed by Pakdeevaraporn et al (2005) and Mahasuk et al (2009a), who crossed PBC932 (C. chinense) with 'Bangchang' (C. annuum). These authors noted that resistance was controlled by one gene (co1) in green fruit, by another (co2) red fruit, and yet another (co3) in seedlings, when using a C. capsici isolate identified as '158ci'.…”

“…In Capsicum genus, resistance control depends on the plant organ under study, such as leaf or fruit (Mahasuk et al, 2009a). In the case of fruit, resistance may also vary with maturation stage, whether immature or mature (Silva et al, 2014;Sun et al, 2015;Suwor et al, 2015).…”