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crop production and corresponding economic benefits to growers. Thus, the effective production of high-quality seedlings is of great significance for researchers and farmers. Morphological and physiological characteristics of vegetable seedlings are
Benzylaminopurine and chlorflurenol were applied to 2-1 nursery stock of Scots pine and ponderosa pine and 2-0 nursery stock Colorado blue spruce and Black Hills spruce to determine if crown morphology was influenced by varying combinations of the two plant growth regulators. Four levels of benzylaminopurine, 0, 250, 750 and 1250 ppm, and two chlorflurenol levels, 0 and 1% (v/v) were tested. Morphological response to treatments was significantly enhanced when treatments were applied to open, elongating buds. Benzylaminopurine significantly increased bud and shoot formation, while chlorflurenol significantly reduced height and increased branch length at species dependent concentrations. The two plant growth regulators lacked positive synergistic effects.
the range of phenotypic responses observed at diverse growth locations in a 2-year project. We report on the variation observed in bulb elemental composition and morphological characteristics of the 10 garlic cultivars across the diverse growth
Runners from 318 plants representing 37 populations across the northern tier of US states, from Washington to New York, were collected and planted in two replications in a common greenhouse environment to assess morphological variation among octoploid strawberries (Fragaria chiloensis, F. virginiana spp. glauca and F. v. spp. virginiana). DNA was also extracted from these plants to determine molecular variation using RAPD's (Random Amplified Polymorphic DNA). Preliminary data suggest that the following morphological characters are useful traits in assessing diversity: flowering and runnering date; sex; petiole and peduncle hairs; petiole and peduncle color; leaf color, size, shape and density; and powdery mildew resistance. Preliminary RAPD data has revealed many useful molecular markers capable of detecting variability from the intrapopulation to interspecific level. Analysis of these data will determine relative genetic distances among the populations and provide a more complete understanding of the diversity available to the strawberry breeder in the octoploid taxa native to North America.
Linkage relationships among eight isozyme genes (Acp-3, Est-1, Est-5, Prx-1, Prx-2, Prx-3, Me, and Adh) and two morphological markers (Inh and Twh) were investigated in one F2 and two BC1 families of interspecific crosses between the American chestnut (Castanea dentata Borkh.) and the Chinese chestnut (C. mollissima Blume). Inh was consistently linked with Prx-1 and Est-5 in all families. In addition, four other gene pairs, Acp-3–Inh, Acp-3–Prx-1, Me–Inh, and Twh–Inh, were linked in one of the three families investigated. The two isozyme genes and two morphological marker genes were tentatively integrated into one linkage group with the gene order Twh–Inh–Prx-1–Est-5.
We characterized a population of hybrids between English walnut and Northern California black walnut (Juglans regia X J. hindsii) and their backcrosses (BC) using both genomic markers and morphological traits. ANOVA and regression methods were used on three years' data to identify a subset of five variables that describe the morphological variability among backcross populations and their parents (R2 = 0.89). Genomic markers were identified using randomly amplified polymorphic DNA (RAPD). A subset of 60 markers specific to the donor species (J. hindsii) were scored in 50 backcrosses to estimate the percent recipient genome in each evaluated BC. The backcrosses were ranked using each method of evaluation; correlation between the ranks was 0.423 and highly significant. Each evaluation method has advantages but neither was able to reliably identify elite progeny.
Eight populations including Ipomoea batatas and I. trifida species were assayed at six polymorphic enzyme loci. Differences in allele frequencies among populations allowed distinction of the two species and among levels of ploidy. Principal component and cluster analyses using isozyme and morphological data were performed. Results from isozyme characterization in general supported the results from morphological classification. Cluster analysis from isozyme assays indicated that the hexaploid species I. trifida is not a different species than I. batatas but may be a wild type. Significant deviations of genotypic frequencies from Hardy-Weinberg equilibrium in some of the loci were detected and were possibly due to effects of natural selection; this fact was reflected in the level of homozygosity observed among populations for the loci in disequilibrium.
Parthenolide, a biologically active sesquiterpene lactone found in feverfew [Tanacetum parthenium (L.) Schultz. Bip.], has been indirectly linked to the antimigraine action of feverfew preparations. Commercial products of feverfew leaves vary widely in parthenolide content (0-1.0%/g dwt). No comprehensive studies have quantified parthenolide variation among feverfew populations or cultivars, and whether morphological traits are correlated with this natural product. In this study, 30 feverfew accessions were examined for parthenolide content, morphological traits, and seed origin. Statistically significant differences in parthenolide levels were found among the populations studied. Parthenolide content ranged from (0.012% ± 0.017 to 2.0% ± 0.97 /g dwt) as determined by HPLC-UV-MS. Higher parthenolide levels tended to be in wild material (0.41% ± 0.27) as opposed to cultivated material (0.19% ± 0.09). Parthenolide levels correlated with flower morphology: disc flower (0.49% = B1 0.36), semi-double (0.38% ± 0.13), double (0.29% ± 0.16), and pompon-like flower (0.22 ± 0.14). Leaf color also appeared to be indicative of parthenolide levels, with the light-green/golden leafed accessions showing significantly higher parthenolide content than darker-leafed varieties, but whether this was due to inadvertent original selection of a high parthenolide-containing golden leaf selection is not yet known. This study does show that further selection for improved horticultural attributes and natural product content is promising to improve feverfew lines for the botanical/ medicinal plant industry.
Dracaena sanderana `Ribbon' plants were grown under 47%, 63%, 80%, and 91% shade. After 15 weeks of growth, plants exhibited marked changes in various morphological features. In order to precisely compare leaves of plants grown under different light levels the Plastochron Index (PI) of Erickson and Mickelini (1957) was used. The plastochron was defined in terms of leaf length. Various leaf morphological characteristics were examined and correlated with 1) actual leaf numbers, and 2) with leaf developmental age. A comparison between the two methods 1) and 2) revealed that overall trends displayed by leaves with a Leaf Plastochron Index (LPI) from 12 to 2 were similar to the same trends linked to actual leaf numbers. However, leaves with LPIs lower than 2 showed that under 80% and 91% shade these leaves had higher values for all studied parameters. Comparable leaves of plants in 91% shade had consistently higher values of the leaf parameters compared to plants in other shade treatments. The use of the PI enabled us to accurately compare morphological differences between plants grown under diverse light conditions.
Bulgaria is famous for its 330-year-old-tradition in rose oil production, which is based on the Kazanluk rose (Rosa damascena Mill. f. trigintipetala Dieck.). The Bulgarian rose oil (otto) is recognized as the ultimate rose oil. For successful selection and breeding work of oil-bearing roses, information is needed on the variation of morphological and phenological characteristics and essential oil composition of locally available genotypes. We estimated the correlation coefficients between yields and morphological characteristics of 15 genotypes of Bulgarian oil-bearing rose. It was found that rose yields depended mostly on the number of flowers, the number of flower branches per bush, and the weight of individual flowers (r = 0.99, 0.88, and 0.84, respectively). Also, we established correlations between the concentrations of various essential oil constituents of the Bulgarian rose oil. Generally, higher concentration of citronellol + nerol was associated with lower concentration of geraniol and stereo-terpens (r = –0.76 and –0.59, respectively). Also, higher concentration of citronellol + nerol was positively correlated to increased concentration of terpene aldehydes (r = 0.63) and esters (r = 0.48). The geraniol concentration was positively correlated to stearoptenes (r = 0.57). Both morphological characteristics and essential oil constituents should be used for further selection of high-yielding cultivars with desirable essential oil composition.