Resistance to color rot have been reported in L. esculentum, L. pimpinellifolium and L. peruvianum. In order to enlarge the scope of the genetic sources of resistance we tested 24 accessions of wild species and 41 lines possessing resistance to other diseases or different genetic features form the "Maritza" Vegetable Crops Research Institute using the inoculation method of Andrus et al. (1942) and evaluation rating of 5 grades.
High level of resistance to color rot was found in L. humboldtii 8760009 (first report), L. pimpinellifolium 88610002 and a local primitive L. esculentum 86E2208. The moderate resistance found in L. flammatum and L. chilense 87610011 is reported for the first time.
The resistance found in the following lines from our gene bank collection is of greater interest: 1207/87 TmC.m., 1208/87 VF2NSm, 2777/86 C5 with a degree of damage of 0,4 - 0,9 compared to 4,00 of the susceptible control. Moderate level was noted with the lines 3883/86 (MSU-USA), 1223/87 M, 2769/86 C5, 1215/87 FC.m. Ps,sol., 2772/86 Cf, and 2781/86 C5. Some of the results are shown in Table 1.
Table 1. Reaction of some species and lines to color rot phase of Alternaria solani.
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Degree Degree
Species of damage Lines** of damage
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86E2208* L. esculentum 0,80 1207/87 TmC.m. 0,50
88610002 L. pimpinellifolium 0,69 1208/87 VF2NSm 0,90
87610005 L. racemigerum 0,75 2777/86 C5 0,92
87610003 L. humboldtii 0,30 3883/86 uSU - USA 1,17
L. flammatum** 1,20 1223/87 M 1,29
87610013 L.hirs.glabratum 1,67 2769/86 C5 1,33
87610010 L. peruvianum 2,30 1215/87 F C.m.Ps.sol 1,50
L. peruvianum** 0,60 2772/86 C5 1,60
87610009 L. glandulosum 1,82 2781/86 C5 1,77
87610011 L. chilense 1,27 S-control 4,00
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* Cat. nos from the Institute of Plant Introduction and Genetic Resources** The "Maritza" Vegetable Crops Research Institute's collection.
Literature cited:
Andrus, C.F. et al. 1942. J. Agr. Res. (US) 65, 339-346.
Barkdale T. H. and A.K. Stoner. 1977. Plant Dis. Reptr. 61, 61-65.