Search Results
Abstract
Fruit of tomato (Lycopersicon esculentum Mill.) illuminated with red, blue, green, and white lights at the same radiant energy level were compared with controls kept in the dark for texture, color and solids and acid content during the ripening period. Red light was the most effective of the various light sources in softening of the tissue and in lowering the reflectance value in the early stages of ripening. Blue light was most effective in producing the enhancement of red hue in the later stages of ripening. Little effect on solids and acid contents was noticed.
Effects of temperature and photoperiod on growth rates and morphological development of Dahlia pinnata Cav. `Royal Dahlietta Yellow' were determined by growing plants under 45 combinations of day and night temperatures (DT and NT, respectively, and photoperiod. DT and NT ranged from 10 to 30C and photoperiods from 10 to 24 hours·day-1. Photoperiod influenced vegetative development more than reproductive development as plants flowered in all photoperiods. Lateral shoot count and length decreased and tuberous root weight increased as photoperiod decreased from 16 to 10 hours. Temperature interacted with photoperiod to greatly increase tuberous root formation as temperature decreased from 25 to 15C. Increasing temperature from 20 to 30C increased the number of nodes below the first flower. Flower count and diameter decreased as average daily temperature increased. Nonlinear regression analysis was used to estimate the maximum rate and the minimum, optimum, and maximum temperatures for leaf-pair unfolding rate (0.29 leaf pair/day, 5.5, 24.6, and 34.9C, respectively), flower development rate from pinch to visible bud (0.07 flower/day, 2.4, 22.4, and 31.1C, respectively), and flower development rate from visible bud to flower (0.054 flowers/day, 5.2, 24.4, and 31.1C, respectively). The results collectively indicate a relatively narrow set of conditions for optimal `Royal Dahlietta Yellow' dahlia flowering, with optimal defined as fast-developing plants with many large flower buds and satisfactory plant height. These conditions were a 12- to 14-hour photoperiod and ≈ 20C.
Abstract
6-Furfuxylamino purine (kinetin) at 0.1% plus indoleacetic acid (IAA) at 0.005 to 0.025% in lanolin, applied directly to the lateral buds at nodes on the basal portion of stems induced aerial crown formation with shoot growth.
Dahlia “Royal Dahlietta Yellow” plants were grown in controlled temperature chambers under 25 different day and night temperature environments ranging from 10°C to 30°C. The day length was 12 hours with an average PPF level of 300 micromolm-2 s-1 at canopy level. Leaf unfolding rate, shoot elongation and flower development rate were determined and models developed. Leaf unfolding rate increased as temperature increased up to 25°C. Stem elongation increased as the difference between day and night temperature increased. Flower initiation was delayed at high (30°C) temperature and flower development rate increased as temperature increased from 10°C to 25°C. Plants are currently being grown under greenhouse conditions to provide data for validating the models.
Abstract
Polyphenol oxidase of peach (prunus persica (L.) Batsch) was reversibly bound to and eluted from phenyl-sepharose CL-4B, a hydrophobic resin. Purification of the enzyme was considerable. Hydrophobic chromatography resulted in purification, removal of inhibitory substances, cocentration, and separation of the polyphenol oxidase in isoenzyme forms in a Single step.
Abstract
Asparagus plants freed of 3 viruses were obtained by aseptic culture of shoot tips and apical meristems. More plantlets developed from shoot tip cultures than from apicalmeristem cultures, but a much larger proportion of the meristem cultures were virus free. Consequently, the number of virus-free plants obtained by these 2 methods were approximately equal. The ease of excising and culturing shoot tips makes this the preferred method. The aseptic stock plants obtained are being used as the source of propagants for mass production of virus-free asparagus plants.
Abstract
More rooted Asparagus officinalis L. plantlets were obtained in vitro from stem segments with 3 or more branch-shoots than from those with 1 or 2 branch-shoots; those without branch-shoots produced the fewest plantlets.
Abstract
One-bud segments from moderately vigorous shoots of aseptically grown Asparagus officinalis L. stock plants were cultured on modified Murashige and Skoog’s medium (MMS) containing 0.1 ppm of α-naphthaleneacetic acid (NAA) and 6-furfurylamino purine (kinetin). Only 35% of the cultures developed into rooted plantlets. A high percentage of nonrooted plantlets were induced to root by reculturing on fresh MMS medium containing 0.1 ppm NAA. More plantlets rooted if they were older than 4 weeks when recultured on the fresh medium.
Abstract
Survival of Asparagus officinalis L. transplants in soil was significantly improved with a minimum of labor when they were first transplanted into the Jiffy 7 peat pots from aseptic culture and grown under intermittent mist for 5 to 8 days.
Abstract
Asparagus is generally propagated by seed and occasionally by crown division. Crowns are usually formed underground at the base of stem (1, 2, 3, 4). To our knowledge, the formation of crowns at above-ground nodes and plant development therefrom has never been reported. Occurrence of such crowns opens the way to a rapid means of vegetative propagation. Here we describe the morphology of aerial crown formation and subsequent development of these crowns into apparently normal plants.