Search Results
Abstract
Research efforts aimed at producing haploid plants by tissue culture of anthers or isolated pollen grains have increased recently. Likewise, the ability of the plant breeder to utilize haploid plants in the breeding program has added a new dimension and possible efficiency to the manner in which horticultural crops can be genetically improved. This review will discuss the recent progress that has been made in the art and science of anther and pollen culture to produce haploid plants and the potential for use by horticultural plant breeders. Previous reviews on this subject have been published by Bottino (12), DeBerg (24), Kimber and Riley (49), Melchers (57, 58), Smith (87), Sunderland (89) and the publication Haploids in Higher Plants – Advances and Potential from the first international symposium held in this area of plant biology, at Guelph, Ontario in 1974.
Abstract
Fresh indoleacetic acid oxidase (IAA-OX) preparations from the shoot tips of double flowered genotypes, DD and Dd, and single, dd, flowered petunias (Petunia hybrida Hort.) generally exhibited no lag-phase and had similar rates of IAA destruction. Water-soluble, heat-stable fractions from the 3 genotypes inhibited the destruction of IAA by horseradish peroxidase (HRP) and the IAA-OX preparations. The inhibitor fractions behaved similar to ferulic acid which induced a 10 to 20 minute lag-phase. In all combinations of inhibitor fraction and IAA-OX preparation or HRP, neither the length of the lag-phase nor the subsequent rate of IAA destruction was correlated with the genotypes investigated.
Abstract
Phenolic compounds extracted from leaf tissue of 8 poinsettia cultivars (Euphorbia pulcherrtma willd. ex. Klotzsch) grown in a vegetative state were analyzed using 2-dimensional paper chromatography to determine if they could be biochemically distinguished. Six of the 8 cultivars studied, closely related on the basis of presumed ancestry and previous biochemical studies, exhibited similar chromatographic patterns. The other two cultivars, each having diverse, unrelated genetic backgrounds, exhibited only minor differences in their phenolic profiles. Therefore, two-dimensional chromatographic analysis of phenols did not successfully aid in cultivar identification.
Abstract
Three sets of Petunia hybrida Vilm. lines were used with each set comprised of the 3 genotypes, multiflora (gg), grandiflora (GG), and heterozygote (Gg). Seed germination was consistently high for the hybrid Gg (92%), intermediate for gg (77%) and low for GG (45%). The fresh and dry wt of 28-day-old seedlings was inconsistent but the Gg hybrid was the most vigorous at 49 days followed by the gg and GG genotypes. No differences were observed in N, P, K, Na, Mn, Fe, Cu, Zn, or Al in vegetative leaves of the 3 genotypes. Differences in Ca, Mg, and B occurred, but they were not uniform with respect to genotype or to genotypes within a set. Calcium and Mg were generally highest in gg and lowest in GG. Boron in 1 of 2 experiments showed the same pattern. The physiological roles of the observed differences in elemental composition with respect to chlorophyll composition, sugar metabolism, and vigor as indicated by an increase in fresh and dry wt, in the 3 genotypes are discussed.
Abstract
An investigation of free amino acids, phenols, and indoles from various plant parts of double (DD and Dd) and single (dd) flowered petunia plants was made to determine if a relationship exists between these substances and flower genotype. There was no difference between genotypes in total free amino acid concentration from shoot tips or anthers. Flower buds with the DD genotype and leaves with the Dd genotype were significantly different in total amino acid concentration from similar tissue of the other genotypes. TLC analysis of amino acid extracts from shoot tips, buds, or leaves failed to resolve any qualitative differences between the 3 genotypes. Anthers directly squashed on TLC plates and developed in several solvent systems did not resolve any differences between genotypes. TLC analyses of phenols and indoles indicated they were very similar for the 3 genotypes.
Abstract
Specific auxin-containing formulations which contained primarily indolebutyric acid (IBA), and/or napthaleneacetic acid (NAA) were most effective in promoting rooting of terminal stem cuttings of poinsettia (Euphorbia pulcherrima Willd.).
Abstract
Leaf explants excised from in vitro grown, open-pollinated seedlings of ‘Golden Delicious’ apple (Malus domestica Borkh.) and placed on Murashige and Skoog (MS) medium, containing B5 vitamins, 30 g/liter sucrose, and 8 g/liter agar supplemented with 10.0 mg/liter 6-benzylamino purine (BA) and 3.0 mg/liter naphthaleneacetic acid (NAA) produced low frequencies of globular to heart-shaped embryoids. The early embryonic states were observed after 3 to 4 weeks of incubation in the dark but not on cultures placed in the light. Upon excision and transfer to MS medium with or without 3.0 mg/liter BA plus 0.3 mg/liter NAA, most of the embryoids did not undergo further development; however, 6 did attain the cotyledonary stage. Two of these eventually developed into bipolar structures which gave rise to intact plants.