A double-flower form of Nicotiana alata Link & Otto was characterized genetically as a monogenic recessive trait expressed when homozygous. Reciprocal crosses demonstrated no maternal effect on expression of double flowers. A single dominant gene expressed in the homozygous or heterozygous state caused the single-flower phenotype. The symbol fw is proposed to describe the gene controlling double-flower phenotype.
Rozlaily Zainol and Dennis P. Stimart
Rozlaily Zainol, Dennis P. Stimart, and Ray F. Evert
Anatomical analysis was performed using a double-flowered mutant of Nicotiana alata Link & Otto. Flower doubleness resulted from petaloid modification of the androecium. Vascularized petal-like outgrowths arose from the anther, connective, and filament of the stamen. The vasculature in petaloid outgrowths from the anther and upper part of the filament originated from and was continuous with the vascular bundle of the filament. In contrast, the vascular bundles formed in the outgrowths from the lower part of the filament developed independently of the vascular bundle of the filament and were not connected to it at any time. Emergences consisting of epidermal and ground parenchyma tissue and lacking vascularization arose from the filament.
Jennifer K. Boldt, James C. Locke, and James E. Altland
nonaccumulators. Frantz et al. (2010) grew 48 horticultural crops hydroponically in a modified Hoagland’s solution amended with 1 m m Si and quantified foliar Si concentration. It ranged between 102 and 12,682 mg·kg −1 Si [ornamental tobacco ( Nicotiana
Jennifer K. Boldt and James E. Altland
, grown hydroponically in a modified Hoagland’s solution amended with 1 m m Si, and they found it to range between 102 mg·kg −1 [ornamental tobacco ( Nicotiana sylvestris Speg. & Comes.)] and 12,682 mg·kg −1 Si (zinnia). Plant Si concentration can vary