1. Theor Appl Genet. 2011 May 13. [Epub ahead of print]

The inheritance of resistance to Verticillium wilt caused by race 1 isolates of
Verticillium dahliae in the lettuce cultivar La Brillante.

Hayes RJ, McHale LK, Vallad GE, Truco MJ, Michelmore RW, Klosterman SJ,
Maruthachalam K, Subbarao KV.

United States Department of Agriculture, Agricultural Research Service, Crop
Improvement and Protection Unit, 1636 E. Alisal St, Salinas, CA, 93905, USA,

Verticillium wilt of lettuce caused by Verticillium dahliae can cause severe
economic damage to lettuce producers. Complete resistance to race 1 isolates is
available in Lactuca sativa cultivar (cv.) La Brillante and understanding the
genetic basis of this resistance will aid development of new resistant cultivars.
F(1) and F(2) families from crosses between La Brillante and three iceberg
cultivars as well as a recombinant inbred line population derived from L. sativa 
cv. Salinas 88  La Brillante were evaluated for disease incidence and disease
severity in replicated greenhouse and field experiments. One hundred and six
molecular markers were used to generate a genetic map from Salinas 88  La
Brillante and for detection of quantitative trait loci. Segregation was
consistent with a single dominant gene of major effect which we are naming
Verticillium resistance 1 (Vr1). The gene described large portions of the
phenotypic variance (R (2) = 0.49-0.68) and was mapped to linkage group 9
coincident with an expressed sequence tag marker (QGD8I16.yg.ab1) that has
sequence similarity with the Ve gene that confers resistance to V. dahliae race 1
in tomato. The simple inheritance of resistance indicates that breeding
procedures designed for single genes will be applicable for developing resistant 
cultivars. QGD8I16.yg.ab1 is a good candidate for functional analysis and
development of markers suitable for marker-assisted selection.

PMID: 21567237  [PubMed - as supplied by publisher]

File with the genotypes for polymorphic markers in population Salinas 88 x La Brillante: