You are looking at 1 - 10 of 15 items for
- Author or Editor: Stephen A. Garrison x
The effect of soil moisture levels on the yield and dry matter accumulation of asparagus (Asparagus officinalis L) using the motherstalk method was examined in a greenhouse study. This technique allows for a spear to develop a mature fern while permitting harvest of later-developing spears. The motherstalk treatment resulted in significantly heavier spears as compared to the conventional practice without a motherstalk and harvesting all spears. In addition, crown weights between the motherstalk and the nonharvested treatment were similar at the end of the 12-week harvest period, but significantly lower when spears were harvested without the benefit of a motherstalk. Optimizing soil moisture significantly increased yield in the motherstalk treatment and increased the fern dry weight but had no effect on crown dry weight. Our results indicate that the motherstalk system may allow for extended asparagus harvest in temperate areas but soil moisture may need to be carefully monitored to use this technique.
The motherstalk method of `Jersey Centennial' asparagus production was examined in two greenhouse studies. This technique allowed for one, two, or three spears to develop a mature fern while permitting harvest of later-developing spears. Cumulative yield was highest 10 weeks after planting with one and two motherstalks, and crown dry weights in these treatments were similar to those of the nonharvested treatment. In a second experiment, spear yield and crown dry weight were determined when the motherstalk was initiated at 0, 2.5, and 5 weeks after planting. Yields were highest when the motherstalk was established at week 0 or 2.5 compared to week 5. Crown dry weights of early motherstalk treatments were similar to those of the nonharvested treatment at the end of the 10-week harvest period. Our results indicate that the motherstalk system may allow for extended asparagus harvest in temperate areas.
Detached fruits of the rin mutant in tomato (Lycopersicon esculentum Mill.) synthesized little or no lycopene in the presence of 10, 100, or 1000 ppm ethylene in air. However, lycopene synthesis was initiated in fruits kept in 60% or 100% O2 (elevated tensions of oxygen) in the presence of 10 ppm ethylene.
Asparagus (Asparagus officinalis L.) root tissue added to soil at 2, 4, or 6g (dry weight basis) per 100 g of dry soil generally inhibited lettuce and delayed tomato and asparagus seedling emergence when incorporated in soil for 0 or 28 days before seeding. The toxicity of the 2 and 4 g rates of asparagus root tissue was diminished after 50 days, but the 6 g rate inhibited and/or delayed emergence 50 and 90 days after incorporation in soil. These results suggest that asparagus root tissues contain a hetero- and auto-toxic allelopathic compound(s) that is inactivated with increasing time in the soil.
Asparagus (Asparagus officinalis L) was established in the field from 9 and 12-week-old greenhouse-grown seedlings and by direct seeding. Initial and over winter survival of transplants was not affected by age of seedling, method of growing, or the use of the an transparent Wilt-Pruf. Transplants produced more shoots, were taller and exhibited higher survival than seedlings established by direct seeding.
An RCB (4 replicates - 4 m plots) planting of `Chandler' was established to test the effects of planting date and floating row covers (FRC) in a high density strawberry planting system under NJ conditions. Transplant “plugs” from runner tips were planted on a double row (0.5 m × 0.3 m) on a raised plastic mulch bed (1.5 m centers), with trickle irrigation. Treatments included: plant 9/18/91 w/FRC on 10/7/92; plant 9/18/91 w/FRC on 12/2/92; plant 9/18/91 w/noFRC; plant 10/7/91 w/noFRC; plant 9/14/92 w/FRC on 10/7/92; plant 9/14/92 w/noFRC. In 1992, `Chandler' yield increased with earlier planting date and earlier FRC application (range: 8,600 to 13,400 kg/ha). There were no significant differences in cull or fruit weight. In 1993, there were no significant differences in 2nd year yield for 1991 treatments (range: 19,198 to 20,531 kg/ha). However, the 1992 treatments again showed the benefit of FRC (range: 13,437 to 20,531 kg/ha) for improved first year production. One year old plots had significantly larger average fruit weight than two year plots (range: 10.3 to 13.7 g). Early planting date with early applied FRC was the best treatment, combining high yield and good fruit weight.
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.
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.
Chandler strawberries were planted on plastic mulch in September and renovated at various times after harvest during the next summer. Renovation treatments included mowing, thinning to three crowns/plant, and mowing plus thinning. These treatments were applied to 1-year-old and 2-year-old beds of `Chandler' strawberries. We conducted this study over two harvest seasons to compare winter conditions and the influence of polyester rowcovers. The second harvest season had severe winter temperatures (–5F), along with frequent ice accumulation. Marketable yields, culls, and fruit size were determined from each treatment. Yields varied with the time of treatment and with the degree of winter severity. Fruit size of renovated berries was smaller than first year berries, but still marketable. Polyester covers increased early yields.
One-year-old crowns of `Jersey Giant' asparagus (Asparagus officinalis L.) were forced into spear production at 28C in darkness. Total spear fresh weight and number per square meter responded quadratically to the percentage of sand incorporated in Pro-Mix BX (PMX) peat-lite medium, with maximum yields at 25% to 75% (by volume) PMX. In a second study conducted at 22 and 28C, total spear fresh weight and number per square meter for 96 days of harvest were similar when grown in weathered, spent mushroom compost (SMC) or 1 PMX: 1 sand (v/v), but were lower than those grown in PMX. The lower temperature caused heavier individual spears, while the higher temperature stimulated earlier spear production. During the first month of harvest at 22C, the total number and fresh weight of spears in SMC were 11% and 17% less, respectively, than in PMX. SMC may be a low-cost forcing substrate for white asparagus.