摘要:

Correlations affecting restitutional behavior in the gametophore are examined. In short stem segments a direct relationship is found between the length of the segment and the number of regenerates; in longer segments this relationship disappears. No such correlation exists between leaf size and number of regenerates per leaf. The presence of leaves increases regeneration from the stem; the stem inhibits regeneration from the leaf.Isolation and not wounding is shown to be the most important factor in leaf regeneration.The apex of the gametophore inhibits both regeneration from the base of the gametophore and bud reactivation. These apical dominance effects can be replaced by the application of indoleacetic acid (IAA) to the tips of decapitated plants. Similar concentrations of IAA and γ-phenylbutyric acid (PBA) inhibit regeneration from both isolated stems and leaves; at lower concentrations some promotion is found with IAA, none with PBA. Shorter exposure of leaves to these compounds results in reversible inhibition, or even an increase in regeneration. IAA and PBA do not counteract each other in their effects.Leaves isolated from intact and decapitated plants show differences in regenerative behavior when treated with IAA. This indicates that IAA could be involved in the inhibition or regeneration from attached leaves.It is concluded that IAA is not the primary factor in the control of correlative inhibition of restitution in the gametophore.

ISSN:0008-4026    

DOI:10.1139/b59-011

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

TheF2lines of monosomics of Chinese Spring by S-615 were compared with normalF2lines for stem solidness. The solid stem index of each plant was determined by totalling index numbers (ranging from 1 for thin-walled, hollow, to 5 for completely solid) assigned to cross sections of the culm at seven designated points. As both the normal and monosomic lines showed a continuous distribution of this index, the factorial analysis was not too reliable. The normalF2gave an estimated difference between the parents of at least four genes; the monosomic XIIIF2, which was more solid than the normal, gave a difference of three genes.Quantitative differences between monosomicF2lines and the normal indicated that chromosomes II, XIII, and XX, comprising homoeologous group 2, tend to make the culm hollow. Chromosomes XIX and XXI also inhibit pith development. Of these five chromosomes, XIII has a gene for hollow culm in Chinese Spring only; XIX, XX, and XXI, which are in the D genome, are effective in both S-615 and Chinese Spring, and II is inconclusive. Chromosome VIII in Chinese Spring promotes pith production. The chromosomes of S-615 bearing genes for solid stem were not identified by this method, as a monosomicF2analysis does not reveal recessives present only in the variety being tested.

ISSN:0008-4026    

DOI:10.1139/b59-012

出版商:NRC Research Press    

年代:1959

数据来源: NRC

摘要:

The genusLotus(Leguminosae) is defined as includingTetragonolobusScop. of the Old World andHosackiaDougl. of N. America, butDorycniumVill. andBonjeaniaReichb. are rejected. There is no single character common to all N. American species which would justify retainingHosackiaas a separate genus. Four subgenera are proposed: 1.Pedrosia(Lowe) Brand, 2.EdentolotusBrand, 3.DeflectostylusCallen subgen. nov., and 4.Tetragonolobus(Scop.) Callen, using characters of the style (other than size) in separating them. On this basis, approximately half the N. American species fall into subgenus 2, the rest into subgenus 3.

ISSN:0008-4026    

DOI:10.1139/b59-013

出版商:NRC Research Press    

年代:1959

数据来源: NRC

ISSN:0008-4026    

DOI:10.1139/b59-014

出版商:NRC Research Press    

年代:1959

数据来源: NRC