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Gerbera seedlings (Gerbera jamesonii H. Bolus Ex. Hook F.) `Florist Strain Yellow' were planted on drip-irrigated, plastic-mulched beds at 24,000, 36,000 or 72,000 plants/ha. Nitrogen and potassium fertilizers at 55, 110, or 220 kg·ha^-1 were factorially combined with populations. In the 1st year of a 2-year study, the number of marketable flowers increased as N and K increased to 110 kg·ha^-1, but as N and K were increased to 220 kg·ha^-1, cull production increased. In the 2nd year, marketable and cull yields increased with N rate to 220 kg·ha^-1; K did not affect yield. As populations increased from 24,000 to 72,000 plants/ha, marketable and cull flower production increased in both years. Flower size and quality were unaffected by plant populations. Nitrogen and potassium fertility did not affect flower size, quality, or vase life in either year.

The objective of this study was to determine the best combination of planting dates (PDs) and cultivars on yield and quality for long-term production of romaine lettuce. `Green Forest' (GF), `Apache' (AP), `Darkland' (DK), `Green Tower' (GT), `Ideal Cos' (IC), and `Tall Guzmaine' (TG) were successfully grown to harvest maturity on 19 PDs from September 1998 to April 2001. Lettuce planted in September and April PDs (pooled over cultivars and year), required as little as 47 and 49 days, respectively, to reach harvest (all cultivars harvested on the same day). Lettuce planted in October, November, February, and March PDs (pooled over cultivars and year), required on average 64, 66, 75, and 67 days to reach harvest, respectively, but in the coldest PDs of December and January, 90 and 98 days, respectively, were needed to reach maturity. Of the eight PDs evaluated, marketable numbers/plot (pooled over cultivars and years) were greatest in the September PD, followed by April (–8% decrease from September PD) > March (–13%) > October (–17%) > November (–21%) > December = January = February (about –30%) and heads weighed the most in September > January = February (–7% decrease from September PD) > March = April (–14%) > October (–21%) > December (–25%) > November (–31%). Cull heads/plot (pooled over cultivars and years) were greatest in April > December (–5% decrease from April PD) > January = February (–16%) > November (–27%) > October (–34%) > March (–44%) > September (–49%). Two out of three November PDs were lost to freezing damage and this PD should be avoided. Significant bolting occurred primarily in the September and October PDs (in 1 of 3 years) with negligible bolting in the November, December, and January PDs, but bolting recurred again in the February, March and April PDs. Marketable numbers/plot (pooled over all PDs and years) were greatest for GF > GT (–7% decrease from GF) > AP (–8%) > IC (–9%) > DK (–11%) > TG (–21%). The interaction effect of cultivar × PD indicated that GF yielded the most marketable heads in 6 out of 8 PDs. The best performing cultivars by PD (pooled over years) were September and February = GF and IC; October = TG; November = AP; December, January, March, and April = GF.

Abstract

Single applications of ancymidol at 0.03, 0.12, 0.50, or 1.0 mg/plant were soil applied to asparagus seedlings (Asparagus officinalis L.) 3.5, 5.5, or 7.5 weeks after seeding. Increasing ancymidol rates from 0.03 to 1.0 mg/plant decreased bud number, fern dry weight, but not shoot number at all application times. When ancymidol was applied at 1.0 mg/plant at 3.5 weeks it reduced fleshy root production, but in plants treated at 5.5 to 7.5 weeks, it did not reduce fleshy root production. Increasing ancymidol rates from 0.03 to 1.0 mg/plant reduced the crown dry weight of plants 5.5 weeks and younger. Ancymidol from 0.03 to 1.0 mg/plant applied to 3.5-week-old plants increased the partitioning of dry matter into fern rather than crowns, but delaying application to 7.5 weeks after seeding reversed this relationship suggesting increased carbohydrate storage. Application of ancymidol from 0.03 to 1.0 mg/plant to plants 5.5-weeks-old or younger was considered detrimental to plant growth. Ancymidol at 0.50 mg/plant or less applied to 7.5-week-old plants enhanced the production of a stocky, compact transplant. Chemicals used. Ancymidol: α-cycloprophyl-α-(4-methoxyphenyl)-5-pyrimidinemethanol.

Abstract

Increasing the P rates from 0 to 20 ppm increased shoot and crown fresh and dry weight, plant height, and fleshy root and bud production in 10-week-old asparagus (Asparagus officinalis L.) seedlings. Increasing K rates from 0 to 200 ppm decreased the production of fleshy roots relative to buds. Shoot production progressively increased as N rates increased from 100 to 200 ppm in conjunction with P rates increasing from 10 to 20 ppm. The partitioning of dry weight into crowns predominated over that partitioned into shoots in any combination of N rate from 0 to 200 ppm, and P rate from 0 to 20 ppm. With P rates held constant at 0 to 20 ppm, however, increasing the N rates from 0 to 200 ppm tended to reduce the partitioning rate into crowns and enhanced partitioning into the shoots. Nutrient solutions containing at least 20 ppm P and 100 ppm N and K are recommended in vermiculite-perlite-peat media natively low in NPK.

Abstract

‘TAMBel-2’ bell pepper transplants (Capsicum annuum L.) were grown in a greenhouse for 39 days in north–south (N–S) oriented trays. About 69% of the plants had monodirectional (one plane pointing either N–S, E–W, NW–SE, or SW–NE) lateral root patterns, 23% had bidirectional (two planes), and 7% had omnidirectional (all around) root patterns relative to a N–S greenhouse tray orientation. Transplants were planted with cotyledons N–S (parallel to the N–S bed), with cotyledons E–W (perpendicular to the N–S bed), and at random, without regard to orientation. These plants subsequently were cultivated either deeply (9 cm) or shallowly (3 cm) 3, 5, and 7 weeks after transplanting. Transplants planted E–W by cotyledon orientation yielded significantly more early and overall marketable pods in contrast to those planted N–S by cotyledon orientation or at random. Deep cultivation decreased productivity in contrast to shallow cultivation and negated any benefit to E–W cotyledon orientation. Root and cotyledon orientations in field-seeded peppers were determined for ‘Hidalgo’, ‘TAM-Mild Chile-2’, ‘TAMBel-2’, and ‘Grand Rio 66’ peppers ≈2 months after field-seeding. At least 95% of the populations in all cultivars had monodirectional root orientations. Generally, orientations were divided equally among N–S, E–W, NW–SE, and NE–SW directions. Cotyledon orientation highly correlated with root orientation in all cultivars.

Feverfew has aspirin-like properties and has been utilized for the treatment of pain, particularly migraine headache. Parthenolide is the sesquiterpene lactone believed to be responsible for the medicinal properties. The potential for utilizing existing tobacco production and handling systems for the production and postharvest handling of feverfew was investigated. In year one, 8 commercial tobacco growers each planted about one-half acre of feverfew (Tanacetum parthenium L. Schulz-Bip.). The yield of dry herb varied among farmers from about 122 to 772 (55 to 350 kg) pounds per half-acre. The parthenolide content of the dried herb from most producers was within the range desired by industry, but four factors precluded its salability: a) presence of foreign matter, primarily weeds; b) excessive ash content due to contamination from sandy soils; c) mold resulting from processing with excessive moisture content, and; d) insect infestation (tobacco beetles Lasioderma serricorne) during storage. All of these limitations resulted from the failure to implement good agricultural aractices (GAPs) and good manufacturing practices (GMPs) during production and handling of the product. A second planting of the feverfew was carried out with strict attention to GAPs and GMPs. In this trial, all of the dried feverfew met the requirements for sale. Here we report on the management of production and handling systems for feverfew that can enable growers to produce high quality herbs that meet the high standards for medicinal use.

Extending the production season of melons (Cucumis melo L.) by using very early and late planting dates outside the range that is commercially recommended will increase the likelihood of developing a stronger melon industry in South Carolina. The objective of this study was to determine if early (February) transplanted melons or later (June through July) planting dates are effective in extending the production season of acceptable yields with good internal quality of the melon cultivars: Athena, Eclipse, and Sugar Bowl and Tesoro Dulce (a honeydew melon). Melons were transplanted in Charleston, S.C., in 1998, 1999, and 2000 on 12 and 26 Feb., 12 and 26 Mar., 9 and 23 Apr., 7 and 21 May, 4 and 18 June, and 2 July and required 130, 113, 105, 88, 79, 70, 64, 60, 60, 59, and 56 days from field transplanting to reach mean melon harvest date, respectively. Stands were reduced 67%, 41%, and 22% in the 12 and 26 Feb. and 12 Mar. planting dates, respectively, in contrast to the 26 Mar. planting date but ≤15% in all other planting dates. Planting in February had no earliness advantage because the 12 and 26 Feb. and 12 and 26 Mar. planting dates, all reached mean melon harvest from 19 to 23 June. Comparing the marketable number of melons produced per plot (averaged over cultivar) of the standard planting dates of 12 and 26 Mar. indicated decreases of 21%, 32%, 36%, 36%, 57%, 57%, and 54%, respectively with the planting dates of 9 and 23 Apr., 7 and 21 May, 4 and 18 June, and 2 July. The most productive cultivar of all was `Eclipse', which yielded significantly more melons per plot in all 11 planting dates followed by `Athena' (in 8 of 11 planting dates), `Tesoro Dulce' (7 of 11 planting dates), and `Sugar Bowl' (2 of 11 planting dates). In our study, any planting date with melon quality less than the USDA standard of “good internal quality” or better (Brix ≥9.0) was considered unacceptable because of potential market rejection. Therefore, the earliest recommended planting date with acceptable yield and “good internal quality” was 12 Mar. for all cultivars; the latest planting dates for `Athena', `Eclipse', `Tesoro Dulce', and `Sugar Bowl' were 4 June, 18 June, 7 May, and 9 Apr., respectively. With these recommendations, the harvest season of melons lasted 40 days from 24 June to 3 Aug. for these four cultivars, which extended the production season an additional 2 weeks longer than the harvest date of last recommended 21 May planting date.

Four bell pepper (Capsicum annuum L.) cultivars were evaluated for yield (total weight of marketable fruit) performance over 41 environments as combinations of 3 years, three planting dates, and seven locations across North Carolina, South Carolina, and Georgia. Cultural practices, including trickle irrigation and double rows planted on black-plastic-covered beds, were uniform across all environments, except for fertilization, which was adjusted at each location based on soil tests. Comparing production over 3 years between the mountain location and the Coastal Plain location in North Carolina, yields were lower on the Coastal Plain. Spring plantings provided higher yields than summer plantings at both locations. Yield increases were obtained from hybrid cultivars over that of the open-pollinated (OP) standard [`Keystone Resistant Giant #3' (KRG#3)] in the summer planting in the mountains compared to the Tidewater Coastal Plain. Across the three-state region, hybrid cultivar yields were higher than those of the OP cultivar for the second spring planting date in 1986 and 1987. Although the hybrid yields were higher than that of the OP standard, the hybrid `Skipper' yielded less than the other hybrids (`Gator Belle' and `Hybelle'). `Gator Belle' generally out-yielded `Hybelle' at all locations, except in Fletcher, N.C. This difference may be related to the relative sensitivity of these two cultivars to temperature extremes, rather than soil or geographic factors, because there was a tendency for `Hybelle' yields to exceed `Gator Belle' in the earliest planting date. Based on the reliability index, the chance of outperforming KRG#3 (the standard) was 85% for `Hybelle', 80% for `Gator Belle', but only 67% for `Skipper'.