Search Results
Abstract
Endogenous gibberellins (GA) and cytokinins (CK) were extracted from asparagus (Asparagus officinalis L.) spear tips, purified, and determined by lettuce hypocotyl and amaranthus bioassays, respectively. There was no quantitative difference in GA-Iike activity between heterogametic male and female spears. The major GA fraction in asparagus spears has 1 OH group. Asparagus spears contain 3 major fractions of CK-like activity. Fraction 1 eluted from Sephadex LH-20 and C18 HPLC columns with or before zeatin-riboside. Fractions 2 and 3 eluted in a similar pattern to IPA-riboside and IPA, respectively. There were higher levels of CK fraction 2 and trends toward higher levels of fraction 1 and total CK in female than in heterogametic male spears. There were also higher CK:GA ratios in female than in heterogametic male spears. The data support the hypothesis that sex in asparagus is controlled in part by CK levels or by CK:GA ratios.
Abstract
Crude aqueous extracts from dead stems, crowns, and roots from both field-grown and tissue-cultured asparagus plants delayed, but did not prevent, germination of asparagus seed. Root extract inhibited root and shoot development of asparagus seedlings grown in growth pouches. Stem and crown extracts reduced root growth but not shoot growth. The extracts of all 3 tissues caused more secondary root formation and root branching. The highest concentration of extract from crown-plus-root tissues, 5 g of tissue/100 ml water, inhibited radicle growth and killed seedlings. Toxicity of the crown-root extract was not reduced by adding activated charcoal to the extract or by autoclaving the extract. These results suggest that toxic substances in dead asparagus tissue are water-soluble and stable and may persist in old asparagus fields.
Abstract
Treatment of spears of pistillate asparagus (XX) with 5000 mg/liter gibberellic acid (GA3) plus 1000 mg/liter 6-benzyl-amino-9-(tetrahydro-2-pyryl)-purine (PBA) or 2000 and 5000 mg/liter GA3 alone induced development of stamens with sterile anthers. Spears of XY staminate genotype treated with 10 mg/liter PBA or PBA plus 50 g/liter glucose had more hermaphroditic flowers with ovules than untreated flowers; seedless fruits developed after pollination. YY staminate genotype developed pistils with styles following treatment of spears with 100 mg/liter PBA or PBA plus 50 g/liter glucose. Some ovules had well developed integuments and chalaza but no embryo sacs. PBA reduced stamen length and increased anther sterility.
Abstract
Standing freshly harvested 21-cm asparagus spears (Asparagus officinalis L.) in 50 ml of 1 mg·liter−1 to 10 g·liter−1 aqueous glyphosate solutions significantly decreased toughening and the amount of fiber and lignin in spears stored at 2.5°C for 10 or 20 days. The effect increased with storage time and concentration, but decreased with distance from the cut end. Depending on the time of harvest and length of storage, 1 g·liter−1 glyphosate increased the usable portion of the spear from 40% to 60%. Chemical name used: N-(phosphonomethyl)glycine (glyphosate).
Abstract
A high concentration of inhibitors which were as high as that of gibberellin (GA)-like substances was found in young asparagus (Asparagus officinalis L.) spears using the rice seedling bioassay, and one of inhibitors was identified as abscisic acid (ABA) by gas chromatography. Endogenous ABA was extracted more thoroughly from the lyophilized materials than from frozen tissue. ABA level was the highest in tops including growing points of spears, and was always higher in the distal half than in the proximal, and higher in the cortex than in the pith. Free ABA levels tended to increase with the development of spears, while bound ABA levels remained the same irrespective of age. Three peaks of ABA were found in crown buds and root tips in March or April, August and December. Presumably asparagus crowns were in the deepest dormancy around the middle of December. Clearly the degree of dormancy from October to January paralleled ABA levels in crown buds and root tips. Endogenous levels of ABA in buds at developing stages was found highest in the resting buds.
in storage roots of Asparagus officinalis L New Phytol. 120 463 473 Fujikawa, S. Jitsuyama, Y. Kuroda, K. 1999 Determination of the role of cold acclimation-induced diverse changes in plant cells from the viewpoint of avoidance of freezing injury J
-senescence removal of asparagus ( Asparagus officinalis L.) fern Acta Hort. 479 427 430 Bradford, M. 1976 A rapid and sensitive method for the quantification of microgram quantities of protein utilizing the principle of protein-dye binding Anal. Biochem. 72 248 254
Abstract
Factors determined to have a pronounced effect on shear-press peak-force values of asparagus, Asparagus officinalis L. included sample size, spear diameter, length of green, and preharvest temperature. Shear-press values were greater following periods of cold weather in early spring. Larger diameter spears had lower peak-force values than smaller spears, indicating that larger spears are more tender than smaller spears. The number and diameter of spears produced by a particular cultivar, and not differences between cultivars, were the characteristics observed to influence shear-press values. Shear-press max peak-force values correlated well with subjective and objective determinations of asparagus fiber.
Abstract
It has long been known that female asparagus plants have a higher mortality rate than males. Several explanations have been postulated, among them, competition by males which are more vigorous. Row maps were made in fields ranging from 1 to 19 years old and the distribution and location of males and females in the rows were analyzed. Statistical analysis indicated that the higher mortality rate of females could not be attributed to competition of adjacent males.
Abstract
Harvesting a young planting of asparagus (Asparagus officinalis L.) for 4 or 6 weeks the second year after transplanting 1-year-old crowns, followed by harvesting for 8 or 10 weeks the third year, reduced yields significantly the fourth year. Carbohydrate levels in asparagus storage roots decreased during harvest and continued to decrease after harvest during fern production. Carbohydrate levels increased in storage roots after stalks had matured, and were restored to preharvest levels by mid- to late summer. All treatments possessed comparable levels of storage carbohydrates by the end of the season. Asparagus storage carbohydrates were identified as fructose-oligosaccharides, which varied considerably in size, mobility, and percent fructose and glucose. The largest oligosaccharides were composed of ∼ 90% fructose, ∼ 10% glucose; molecular weights did not exceed 4,000.