Characterisation of quantitative trait loci (QTLs) contributing to field resistance to yellow spot disease in sugarcane

Code (CO)	MSI05P4135
Author (AU)	Aljanabi, S. M. Parmessur, Y. Kross, H. Dhayan, S. Saumtally, S. Dookun-Saumtally, A.
Title - English (ET)	Characterisation of quantitative trait loci (QTLs) contributing to field resistance to yellow spot disease in sugarcane
Document Type(DT)	periodical article
Date of publication (DP)	2005
Series (SE)	Proc. int. Soc. Sug. Cane Technol.
Source (SO)	25 (2): 550-557
Language of text (LT)	En
Language of summaries (LS)	En Fr Sp
Abstract (AB)	A study was carried out to identify molecular markers linked to yellow spot (Mycovellosiella koepkei) disease resistance, an important disease in the super humid zome of Mauritius. A cross between a resistant variety (M 134/75) and a susceptible one (R 570) was performed, and 227 clones issuing from it were analysed for the inheritance of QTLs controllong resistance to the disease. The population was evaluated for yellow spot infection in two replicated trials in two locations and in two consecutive years. Data for yellow spot infection rate were analysed using single factor ANOVA. The segretation pattern observed for disease resistance, measured in year one, year two and the average of both years, strongly suggested monogenic inheritance of the target trait. The segregation data fitted an expected 3:1 ratio for monogenic dominant inheritance (x2=0.64 at 98 perccent confidence level). There was a highly positive and significant correlation (P=0.0001) between phenotypic data measured in both trials (locations) on plant cane and first ratoon. QTL analysis using QTLCartographer v1.17d and MAPMAKERQTL v1.1 identified a single major QTL located on LG87, flanked by an AFLP marker, actctc10, and an SSR marker CIR12284. This major QTL, which was found linked at 14cM to an AFLP marker, was detected with LOD 8.7, had an additive effect of -10.05 and explained 23.8 percent of the phenotypic variation of yellow spot resistance. One additional QTL was detected with a lower LOD value on LG92 with additive inheritance in sugarcane and only the second reported case of a major gene in sugarcane.
Descriptors - English (DE)	Sugarcane diseases disease resistance yellow spot disease molecular markers AFLP Microsatellite genetic mapping quantitative trait loci DNA markers Mycovellosiella koepkei
Descriptors - Geographic (DG)	Mauritius
Sort Key 1(K1)	Sugarcane: Cane breeding and genetic improvement
Sort Key 2 (K2)	Genetic techniques and protocols
Date record entered (DA)	2005-02-22
Language of analysis (LA)	en
Location (LO)	LIB
Processing status (PS)	CAT
MSIRI Staff (MS)	Biotech Path