Search Results

You are looking at 1 - 10 of 11 items for

  • Author or Editor: Jim E. Wyatt x
Clear All Modify Search
Author:

Many summer squash hybrids initiate flowering by first producing one or more pistillate flowers before the development of any staminate flowers. These first pistillate flowers have no pollen source unless an earlier squash planting is nearby. The objectives of this study were to measure the loss in yield incurred by the absence of pollination and to determine if sex expression in squash could be altered by use of gibberellic acid (GA). `Cougar' summer squash was planted in 12 isolated plots on 13 May; four plots had adjacent rows planted on 3 May to provide pollen for the earliest developing pistillate flowers in those plots. On 28 May, 0.146 L·ha-1 of GA (ProGibb 4®) was applied to an adjacent row in four of the plots planted on 13 May. The four control plots received no treatment. At anthesis, pistillate and staminate flowers were counted daily for 10 days. The first six pistillate flowers that bloomed in each plot were identified and measured (length and diameter) on the day of anthesis, and at 4 and 7 days after anthesis. Fruit were harvested five times at 2-day intervals and data are reported on fruit ≤5.7 cm in diameter. GA had no effect on squash flowering habit. At 4 and 7 days after anthesis, fruit were smaller in plots where no pollen source was available. Early yields were higher for the first two harvests in plots where pollinators were present. A small, early planting of squash should be made to provide staminate flowers for normal growth and development of early fruit on the main summer squash crop.

Free access
Author:

Removing a portion of the foliage of zucchini squash without reducing yield would increase the efficiency of mechanical harvest since less plant material would be passed through the harvester. Pruning 50% of the leaves and petioles at either first or second harvest had no effect on third harvest fruit yield. Primary or secondary fruit growth rates were not affected by leaf removal. Presence of a primary fruit reduced the number of secondary fruit developing to marketable size but the rate of secondary fruit development was similar on plants with one, two, or three fruit. The maximum fruit to develop at one time in this planting was two per plant. Following one or two hand-harvests of zucchini squash, mechanical harvest efficiency will be increased after removal of 50% of the leaves and maturation of two marketable fruit per plant.

Free access
Author:

Comparisons were made between conventional and float system growing methods for tomato (Lycopersicon esculentum Mill.) transplants and subsequent production. Effects of cupric hydroxide application to the interior surface of plant-growing trays were compared to untreated controls. Tomato transplants grown in the float system had higher fresh and dry weights; were larger after establishment in the field; and produced higher early yields of small, medium, and large tomatoes than plants grown by conventional methods. Mean fruit weight was higher from conventionally grown transplants early in the season. Total number of fruit and total yield were not affected by transplant production method. Transplants grown in cupric hydroxide-treated trays were larger and had fewer roots emerging through the bottom of the trays than transplants grown in untreated trays. Cupric hydroxide treatment had no effect on tomato earliness, yield, or mean fruit size.

Full access

Objectives of this study were to determine the effects of lima bean seed size differences and a short chilling period after planting on seedling emergence rate, seedling abnormalities and vigor. Individual seeds of 'Jackson Wonder' lima bean were weighed and placed into one of five size classes: 24-33. 36-41. 44-49, 52-57, and 60-73 g per 100 seed. Seed of each size class were germinated at a constant 23-26C or chilled at 8C for 24 hrs and then moved to 23-26C conditions for the remainder of the study. A 24 hr chilling period after planting had a detrimental effect on subsequent lima bean seedling emergence only from 8 through 11 days after planting. Plant fresh and dry weights were significantly less for the chilled seed treatment. Temperature treatments had no effect on percent normal and abnormal seedlings or primary leaf area. No differences in seedling emergence number or rate were found among seed size classes. Smaller seedclasses had significantly fewer normal and more abnormal seedlings than larger seed size classes. The largest seed class produced seedlings with about two times more fresh and dry weights and leaf area than those from the smallest seed weight class. Plant fresh and dry weights and leaf areas from all seed size classes were significantly different from each other.

Free access

Tomato transplants were grown in plastic foam trays floated in nutrient solutions using a system adapted from tobacco transplant growers. Nutrient solutions were compared which contained equivalent amounts of nitrogen and potassium and either 35 or 70 mg·liter-1 phosphorus (P). Growing media tested were 1) Jiffy-Mix*, 2) Pro-Mix®, 3) horticultural vermiculite, or 4) perlite. The higher P rate caused increases in stem diameter, and in plant fresh and dry weight. Plant height, root dry weight and leaf area were not affected by P rate. Transplants grown in Pro-Mix® had significantly greater plant height and stem diameter than other media. Leaf area, and plant fresh and dry weight did not differ between Pro-Mix* and Jiffy-Mix@. Vermiculite and perlite produced smaller tomato transplants and should not be considered when using this production system.

Free access

Abstract

Transplanting has been one means of obtaining earlier yield in certain spring-grown vegetables (Sams, 1983; Weston and Zandstra, 1986). Studies were conducted in 1987 to investigate the feasibility of transplanting sweet corn (Zea mays L. var. rugosa Bonaf.), which is normally direct-seeded. The objectives were to determine the effects of container type on sweet corn transplant growth and subsequent plant development and ear quality and to compare transplanted and direct-seeded sweet corn under field conditions.

Open Access

Studies were conducted in plastic foam trays in float tanks to investigate effects of aeration of the nutrient solution, tray management after seeding and addition of KNO3 fertilizer to the substrate media on tomato transplant growth. Aeration of the nutrient solution had no effect on rate of tomato seedling emergence or growth, even though dissolved O2 was higher in aerated tanks than in non-aerated tanks. Placing trays in the tanks immediately after seeding caused faster seedling emergence than either delaying placement in the tanks or stacking trays until emergence began. KNO3 at 20 g·kg dry Pro-Mix” media resulted in delayed initial emergence but no differences were found 7 days after planting. Initial tray treatments or addition of KNO3 to the media had no effects on final tomato transplant size.

Free access

Several spacing, cultivar, ethephon and harvest sequence studies were made on summer squash in 1989 evaluating cultural practices which maximized marketable once-over yield of fruit for processing. Optimum spacing was 30 cm within rows and 45 cm between rows. The zucchini and yellow hybrids producing the highest marketable yield were `Classic' and 'Gold Slice', respectively. Ethephon applied at 0.77 kg/ha resulted in higher yield than no ethephon. Harvesting two times followed by a seven day delay before a once-over, destructive harvest produced a marketable yield equal to three harvests/week for three weeks. A prototype mechanical harvester has been used successfully on yellow hybrids; zucchini hybrids require more force for successful fruit separation.

Free access

Reduced and no-tillage vegetable production is gaining in acceptance in the Southeastern United States. Conventional till, strip-till, and no-tillage systems with different methods of nitrogen application in staked tomatoes were studied in Tennessee. Conventional tillage plots were prepared by disking and harrowing, strip till plots were cultivated ≈16 cm deep with a rear-tine tiller (≈50 cm wide), and no-till plots were established in chemically killed wheat with no cultivation. Four nitrogen treatments were applied at 67.2 kg·ha-1 N using liquid KNO3. The treatments included applying the N either 1) in a 54-cm strip or 2) in a 108-cm strip over the row, 3) by banding ≈10 cm on each side of and ≈10 cm below the row, or 4) by injecting into the drip irrigation system in increments of 11.2, 22.4 and 33.6 kg·ha-1 N at 2, 4, and 6 weeks after transplanting, respectively. Tillage had little effect on tomato yield but the strip till and no-till plots allowed cultivation or spraying soon after a rainstorm. The improved trafficability was a distinct advantage over the conventionally tilled plots in the study. Total yield was significantly higher in strip tilled plots, but within fruit size categories (small, medium, large and extra large) no differences were found due to tillage system. The fertilizer treatments in which N was placed in 54- or 108-cm strips over the row produced the highest yield of early large and early extra large fruit, which are usually the most valuable portion of the crop. Banded and injected nitrogen treatments tended to produce large amounts of fruit late in the season, a period when tomato prices are generally lower.

Free access

This study compared conventional tillage (CT), strip tillage (ST), and no tillage (NT) cultures for effects on tomato (Lycopersicon esculentum) fruit production. Within each tillage system, fertilization treatments were 60 lb/acre (67.2 kg·ha-1) of nitrogen (N) applied as potassium nitrate in four ways: a 2-ft-wide (0.6 m) strip over the row before transplanting, a 4-ft-wide (1.2-m) strip over the row before transplanting, N banded 6 inches (0.15 m) to the side and 4 inches (0.10 m) below the plant after transplanting, or applied through the drip irrigation system. A treatment of no fertilizer was included in the 1996 study but was discontinued in 1998 and 1999 because yields were low and this would not be a recommended practice in Tennessee. Tillage treatments had no effect on early small, medium, or large tomato yields. In 2 of the 3 years, either ST or CT treatments resulted in the highest total yields. Highest early yields were often produced by applying N in either 2-ft or 4-ft, strips over the row before transplanting. Highest late-season yields were obtained from plants receiving N applied as a band beside the row after transplanting. Results suggest that tomato yield under minimal tillage (ST or NT) was at least equivalent to CT in most years. When the economic benefits of minimal tillage are considered, these results imply that minimal tillage cultural practices are advantageous in tomato production.

Full access