Plant-breeding; comments on the experiments of Nilsson and Burbank . e fruits of A. Oenothera gigas, a mutantspecies. B. Oenothera Lamarckiana, its parent form. 329 330 PLANT-BREEDING make it flower and produce seeds in its first year. Ordina-rily at least one half of the plants remain in the rosette stage,the remainder producing their stems only late in summeror towards the fall, and thus having hardly time enough todisplay their flowers, and none at all to ripen their fruits. ^Ij^^ ^« - A 3 Fig. 105. A. A rosette of rootlcaves of Lamarcks Evening-primrosein September. B. A similar rosette of
Plant-breeding; comments on the experiments of Nilsson and Burbank . e fruits of A. Oenothera gigas, a mutantspecies. B. Oenothera Lamarckiana, its parent form. 329 330 PLANT-BREEDING make it flower and produce seeds in its first year. Ordina-rily at least one half of the plants remain in the rosette stage,the remainder producing their stems only late in summeror towards the fall, and thus having hardly time enough todisplay their flowers, and none at all to ripen their fruits. ^Ij^^ ^« - A 3 Fig. 105. A. A rosette of rootlcaves of Lamarcks Evening-primrosein September. B. A similar rosette of one of its mutants (OfH. Jc/«////a«5)in the same age. Only in some very favorable years have I succeeded in savingseed from annual gigas plants. Here we have an instance of correlation such as thatbetween hairiness or form of scales and hardiness in winteror resistance to diseases. But here the mutative origin ofthe type affords a direct proof of the vaUdity of our assump-tion that such divergent quaUties may be the effects of thesame internal Fig. io6. The smooth-leaved variety of the Evening-primrose (Oeno-thera laevijolia). a. A side-flower with ovate instead of obcordate jjetals,one of the new, highly variable characters of the new form. 331 332 PLANT-BREEDING By this means the direct observation of mutations sup-ports the conchisions derived from purely comparative in-vestigations. Together tliey teach us the great hiw of correl-ative variability, by which one and the same internal causemay affect different organs and ciuaHties in widely divergentways. This law intimately connects the scientific resultsand methods of selection now in use at the Swedish experi-ment station at Svalof with the principles and achievementsof Burbank in horticultural practice and with numerousother more or less isolated scientific facts and methods ofpractice. It points out the lines for further study of correlations must be carried on on the broadestpossi
Size: 1233px × 2026px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublisherchicagoopencourtpu
