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
Transplants of asparagus (Asparagus officinalis L.) were grown in sand culture under varying ratios of NO3 and NH4. Maximum growth occurred in a nutrient solution with a N ratio of 75% NO3 – N and 25% NH4 – N. Growth was significantly reduced when the N composition was either 100 or 75% NH4 – N. CaCO3 reduced ammonium toxicity but also reduced seedling growth.
Asparagus ( Asparagus officinalis ) is an herbaceous perennial plant in which the above-ground fern senesces and dies in the fall, leaving only the below-ground crown to overwinter. In southern Ontario, where air and soil temperatures of –20 and –5
carbohydrate supply in model callus cultures and shoot tips of asparagus ( Asparagus officinalis L.) Plant Physiol. 158 561 568 10.1078/0176-1617-00312 Kays, S.J. Paull, R.E. 2004 Postharvest biology. Exon Press, Athens, GA King, G.A. Borst, W.M. Stewart, R
Abstract
Dipping asparagus crowns (Asparagus officinalis L.) in 300 ppm dikegulac (Atrinal) solution significantly reduced the time of emergence and the height of asparagus shoots without affecting their fresh and dry weights. The number of shoots at complete emergence was not affected by the dikegulac treatment, but thereafter a significant increase occurred. Of the concentrations tested (0, 200, 300, and 400 ppm), 300 ppm was the most effective. After the top was cut off, the dikegulac treatment did not affect the time of emergence of the second shoots, but it did continue to increase their number. Chemical name used: 2,3:4,6-bis-O-(1-methylethylidene)-α-L-xylo-2-hexulofuranosonic acid (dikegulac).
Abstract
Ten enzymes of asparagus (Asparagus officinalis L.) were examined on both starch and Polyacrylamide gels to identify polymorphic loci useful as genetic markers. Two polymorphic loci were discovered, one a root peroxidase (PER-1) and the other a stem shikimic acid dehydrogenase (skd-1). Electrophoretic analysis of 17 totipotent calli derived from anthers that were heterozygous for PER-1 showed 14 to be heterozygous somatic clones and three to be homozygous doubled haploids. The procedure described represents a significant improvement in efficiency over the current method of sexing and progeny testing for the recovery of gametic genotypes from asparagus anther culture.
Abstract
Asparagus aphid [Brachycorynella asparagi (Mordvilko)] feeding without freezing reduced vigor of asparagus (Asparagus officinalis L.), as measured by crown size, fern growth, root necrosis, and bud number, but did not greatly reduce short-term survival. Freezing dormant crowns for 24 hr at −4.5C killed some crowns and reduced vigor of survivors. Aphid feeding and freezing were synergistic; they reduced survival and vigor of survivors to a much greater extent than either aphid feeding or freezing alone. Aphid feeding resulted in early budbreak and precocious growth. A method for counting aphids per plant was developed.
Abstract
Three- to 4-month-old seedlings of an improved selection of Asparagus officinalis L. cv. Mary Washington were artificially hardened and crowns subjected to controlled freezing tests. Two low-temperature acclimation regimes were used. The first was 3C for 0, 1, or 2 weeks before freezing at 0, −5, or − 10C; the second, 3C for 0, 1.5, or 3 weeks, followed by freezing at 0, −2.5, −4.5, −6.5, or −8.5C. Regrowth tests showed that hardiness increased with 2 and 3 weeks of acclimation, with tolerance to −5 and −6.5C, respectively. Water-stressed seedlings (relative water content at 57%) withstood exposure to −5C, but not to −6.5C; rehydrated crowns and well-watered controls were hardy to −3.5C.
Abstract
After the first full growing season, 9- and 11-week-old asparagus (Asparagus officinalis L.) seedlings transplanted in fall exhibited superior crown and fern characteristics relative to seedlings of the same ages transplanted in spring. Seedlings overwintered in coldframes and planted in the spring matched or exceeded growth of those transplanted the previous fall. The hybrid ‘Jersey Giant’ was superior to an improved selection of ‘Mary Washington’ for all planting dates. Correlations between seedling size at transplanting and after one season’s growth were significant for crown weight (r = 0.82), fern weight (r = 0.65), and fern number (r = 0.60). The importance of seedling size is further confirmed by the superior growth of 11-week-old over 9-week-old seedlings up to 18 months after planting.
Abstract
Thirteen seed treatments were compared to determine the optimal method to produce asparagus (Asparagus officinalis L. cv. Viking) seeds suitable for axenic culture. Treated seeds were examined for microbial contamination by culture on an agar medium and for percent germination by incubation on moistened paper. All treatments that included benomyl in acetone (2.5%, w/v) with 20% household bleach (0.1% sodium hypochlorite) were superior to the other treatments in eliminating bacterial and fungal contaminants without decreasing seed germination. Ethanol (70%) and hydrogen peroxide also decreased contamination levels, but ethanol decreased germination significantly. No evidence of internal contamination was detected when aseptic seeds were germinated and cultured on agar medium. Chemical names used: methyl(1-[(butylamino)carbonyl]-1H-benzimidazol-2-yl] carbamate (benomyl).