Rick (TGC 15:50-51) described lyr which appeared in the progeny of tomatoes collected in Central America. Linkage studies indicated it was close to tf on Chromosome 5.
A beautiful, distinctive, leaf-mutant appeared at HES, Simcoe, Ont. in an F4 selection of the cross "Ont 7615" x a sister line of "Bonnyvee." It is highly unfruitful but usually has a few small elongated fruits with rough blossom ends. Most of the fruits produced in the field are parthenocarpic but occasionally contain one or two seeds. A plant grown in the greenhouse, with hand pollination, produced a number of fruits with limited seed content following selfing and outcrossing. Mutant plants can be readily distinguished in the early seedling stage by the slender cotyledons and strap-shaped first true leaf. After growing two F2 populations to determine linkage and a long search for an appropriate name, I noticed that the picture of lyr on the cover of TGC25 closely resembled the new mutant.
Like Rick, I found no evidence of linkage with n, c-sp, ah or h. Additionally there was no close linkage with on Chromosome 1, wf on 3, m-2 on 6, marm on 9, u on 10 j-2 on 11 nor the unlocated genes fu and vo. We are seldom able to score wt with confidence. However it seemed to be fairly distinct in one population in 1984 and gave the following data: ++109, + wt 18, lyr + 23, lyr wt 14. Neither parent had been recorded as wt. Assuming that lyr and wt were in coupling phase, this suggest a linkage of about 33 units. This adds support to Rick's conclusion that lyr is on Chromosome 5, closely linked with tf. The cross lyr x mc-tf-(wt?) was made in 1981 and abundant F2 seed produced but not grown. This three-point test should locate lyr accurately.