Quantitative trait loci mapping of pubescence density and flowering time of insect-resistant soybean (Glycine max L. Merr.)

Abstract

Analysis of antibiosis resistance to common cutworm (Spodoptera litura Fabricius) in soybean (Glycine max (L.) Merr.) has progressed significantly, but the immediate cause remains unknown. We performed quantitative trait loci (QTL) analysis of pubescence density and plant development stage because these factors are assumed to be the immediate cause of resistance to cutworm. The QTLs for pubescence appeared to be identical to the previously detected the Pd1 and Ps loci controlling pubescence density. We found no candidate loci for flowering time QTLs, although one could be identical to the gene governing the long-juvenile trait or to the E6 loci controlling maturity. None of the QTLs overlapped with the QTLs for antibiosis resistance. To reduce damage to soybean (Glycine max (L.) Merr.) plants caused by herbivorous insects, especially the common cutworm (Spodoptera litura Fabricius, Lepidoptera, Noctuidae) (CCW), breeding programs to develop pest-resistant soybean cultivars have been conducted in Japan. We reported that the soybean cultivar Himeshirazu exhibits effective antibiosis resistance to S. litura (Komatsu et al., 2004). We genetically analyzed this resistance using DNA markers and recognized two quantitative trait loci (QTL) for antibiosis resistance to S. litura located on G. max linkage group M which we named CCW-1 and CCW-2 and which explain 28% and 16%, respectively, of phenotypic variance of antibiosis (Komatsu et al., 2005).The genetics of the resistance has been studied (Komatsu et al., 2005) but its immediate cause remains unknown, although pubescence density is a possible factor. Lambert et al. (1992) reported that pupal weight and duration from hatching till pupation of the corn (maize) earworm (Helicoverpa zea Boddie) were affected by pubescence density when near-isogenic soybean lines differing only in pubescence density were used as diet. It is necessary to clarify the relationship between the resistance of the Himeshirazu soybean cultivar to S. litura and pubescence density for better identification of the mechanisms of resistance to S. litura.The plant development stage is also a possible factor in resistance. Nault et al. (1992) reported that mortality of Pseudoplusia includens (Walker) was lower in larvae reared on soybean at the plant reproductive phase than in larvae reared at the vegetative phase. Within the vegetative phase, plant age affected the growth rate of P. includens larvae (Reynolds and Smith, 1985). The Himeshirazu cultivar matures late (maturity group VIII), later than susceptible, mid-maturity cultivars. This later development could contribute to antibiosis resistance, but this would be difficult to determine because it is difficult to synchronize the development stage of all the materials needed for the bioassay. On the other hand, the late maturity of the Himeshirazu cultivar could be an obstacle for the development of elite pestresistant cultivars, because it is too late for the cultivation program followed in Japan. If late maturity confers resistance, it migh...

Antibiosis Resistance of QTL Introgressive Soybean Lines to Common Cutworm (Spodoptera litura Fabricius)

“…The difference in development stage of the NILs at the bioassay period could be a cause of instability of NIL‐C1+C2. Nevertheless, no QTL for days to flowering has been detected on LG‐M in the F 2 segregating population of Fukuyutaka and Himeshirazu (Komatsu et al, 2007). In addition, NIL‐C1+C2 flowered and matured at the same time as Fukuyutaka in 2005 and 2006, and NIL‐C2 also flowered and matured the same as Fukuyutaka in 2006 (data not shown).…”

Positional Cloning of the Flowering Time QTL qFT12-1 Reveals the Link Between the Clock Related PRR Homolog With Photoperiodic Response in Soybeans

“…Flowering time and maturity regulated by photoperiod sensitivity genes or loci (Garner and Allard, 1927; Cober et al, 2014) have been reported for soybeans, E1 , E2 (Bernard, 1971), E3 (Buzzell, 1971), E4 (Buzzell and Voldeng, 1980), E5 (McBlain and Bernard, 1987), E6 (Bonato and Vello, 1999), E7 (Cober and Voldeng, 2001), E8 (Cober et al, 2010), E9 (Kong et al, 2014), E10 (Samanfar et al, 2017), and J (Ray et al, 1995). Moreover, many other quantitative trait loci (QTLs) have been mapped for flowering time and maturity using different populations (Tasma et al, 2001; Chapman et al, 2003; Watanabe et al, 2004; Funatsuki et al, 2005; Pooprompan et al, 2006; Komatsu et al, 2007; Khan et al, 2008; Liu and Abe, 2009; Cheng et al, 2011; Yamaguchi et al, 2014). A total of 293 QTLs on flowering time and maturity, including 104 QTLs of first flower, 178 QTLs of pod maturity (R8), 5 QTLs for pod maturity beginning (R7), and 6 QTLs for pod beginning (R3), have been documented in the public repository, Soybase ().…”

Genetic transformation of cotton with a harpin-encoding gene hpa Xoo confers an enhanced defense response against different pathogens through a priming mechanism

“…Genes encoding antifungal proteins, such as endochitinase [11], β-1,3-glucanases [12], and glucose oxidase [13], or components of signaling pathways involved in the defense response [14-17], have been used to generate transgenic plants resistant to various plant pathogens.…”