PART I RESEARCH NOTES Al-Kummer, M. K., and I. B. Taylor  Observations on flowering and vegetative development of Solanum lycopersicoides. In response to the research note in TGC Report 29:29 concerning the problems of inducing flowering in Solanum   lycopersicoides (Phills and Robinson, 1979), we thought that it might be instructive to relate our experiences with this species. Using both vegetatively propagated material and seedlings of S. lycopersicoides (P1365 378), we have not yet failed to induce flowering in a growth chamber set at 18 + 1oC, with a short day photoperiod (10 h light/14 h dark) supplied by fluorescent tubes with a light intensity of around 1000 FtC. These conditions approximate the 10-15oC, 1000-1200 FtC regime recommended by Phills and Robinson. The major difference is that they do not specify a daylength and suggest that photoperiod is relatively unimportant. Although we have not conducted extensive tests into the interaction of the three main variables (temperature, light intensity and photoperiod), we have found that under our standard growing conditions the daylength is critical. Two identical groups of S. lycopersicoides have been grown in closely similar growth chambers, both generating 1000 FtC and maintaining a constant 18 + 1oC temperature. One group was subjected to a photoperiod of 10 h light/14 h dark, while the other was given 16 h light/8 h dark. The former flowered profusely whereas the latter group remained vegetative. These results are consistent with our observations of glasshouse grown plants in England. In addition to the flowering problem, we initially encountered some difficulty in maintaining our stock of S. lycopersicoides. Propagating by means of cuttings has presented no problem. With some genotypes young shoots have even arisen from the roots of a mature plant, rendering it unnecessary to take cuttings. We are not aware of spontaneous plantlet formation occurring in any other close relative of the tomato and do not rule out the possibility that these propagating 'roots' are in fact subterranean shoots. In raising plants from seed we have encountered germination problems. Initially this was due to harvesting the fruit prematurely. S. lycopersicoides fruit takes takes an extremely long time to mature and this is only marked by the fruit becoming a slightly paler green. In practice we now leave the fruit on the plants for approximately four months from pollination. Even after this period the fresh seed usually fails to germinate unless the seed coat is cut to facilitate the emergence of the radicle. Avdeyev, Y. I., and B. M. Shcherbinin Ora, the gene for resistance to Orobanche aegyptiaca, may be on chromosome 11. In TGC 27 we reported a tomato line PZU-11 resistant to broomrape, Orobanche aegyptiaca. In the period 1975- 1977, PZU-11 and Bush-Line with the Ora gene were crossed with other varieties and genetic lines. Results show no evidence of linkage between Ora and, sp, d, u, o, t Tm-2, Tm, and O; that is, broomrape resistance segregates independently of these genes. At that time, we tested 55 F2 jointless plants from the cross: PZU-11 x Mashinny (j). We found only one (1.82%) resistant j plant under conditions of severe infection. In 1978 we exposed 256 j plants in the F2 Volganin (j) X Bush-Line (Ora) to standard-level infection. Only 8 plants (3.12%) were resistant to broomrape - i.e., only 1/24 of the number expected. According to these data, we believe that Ora is linked with j on chromosome 11. Campion, B., M. Schiavi, and G. P. Soressi Potential of torosa2 for tomato breeding. To radically solve the problem of mechanically harvesting tomatoes in Italy, we need an ideal plant (ideotype) characterized by upright habit, lack of lateral shoots, and bearing 1-3 fruits in the first truss, at which growth stops.

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