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Tomato spotted wilt virus (TSWV) is a serious constraint to tomato production worldwide. Losses are significant because the disease is difficult to control and most of the commercially available tomato cultivars are susceptible to TSWV. This study was intended to provide information that could be used to design more appropriate disease management strategies. The objective was to determine the relationship of tomato plant growth and fruit yield with the time of TSWV symptom appearance. Experiments were carried out during Spring 1999 and 2000, using drip irrigation and plastic film mulched beds with black plastic mulch alone (1999) or different colored mulches (2000). The mulches used were black, black-on-silver, gray-on-black, red, silver-on-black, silver (painted) and white-on-black, and bare soil. The 1999 experiment included a single TSWV-susceptible cultivar (Florida-47), while the 2000-experiment included two TSWV-susceptible (Florida-91 and Sun Chaser) and one TSWV-resistant cultivars (BHN-444). Colored mulches and tomato cultivars affected the time between transplanting and appearance of first symptoms of TSWV. For all tomato cultivars, vegetative top fresh weight (FW), fruit number and total fruit yield increased linearly with the time the plants remained free from TSWV symptoms. Marketable fruit yield also increased as the time from transplanting to the first appearance of symptoms increased. When data for cultivars were pooled, vegetative top FW and total fruit yield were reduced by 2.1% and 2.3%, respectively, for each day prior to harvesting that plants showed TSWV symptoms.

Commercial vegetable production depends almost solely on inorganic fertilizers. In an era of environmental sensitivity, enrichment of soils with green manures and cover crops may reduce the dependence on these fertilizers while maintaining and enhancing crop yields. The objectives of this research were to determine (1) if supplemental nitrogen (N) at 60 or 120 kg · ha−1 following winter cover crops of wheat (Triticum aestivum L.) or crimson clover (Trifolium incarnatum L.) affect yield of tomato (Lycopersicon esculentum Mill.) and snap bean (Phaseolus vulgaris L.) grown in rotation; and (2) the distribution and retention of soil nitrates in the soil profile as affected by N fertilization and cover cropping. ‘Mountain Pride’ fresh market tomato and ‘Strike’ snap bean were grown in rotation for four years. Clover and wheat cover crops increased total marketable yield of ‘Mountain Pride’ tomato in one out of four years. Total marketable tomato yield increased as fertilizer N increased to 60 kg · ha−...

Planting and first harvest dates of tomato ( Lycopersicon esculentum Mill.) from 2 seasons in 3 years at eight locations in Georgia, North Carolina and South Carolina formed 38 environments which were used to determine the most reliable method to predict fast harvest date of tomato based on daily maximum and minimum air temperature. Eleven methods of calculating heat units were chosen for comparison based on their performance as described in the literature. The most reliable method was defined as the one with the smallest coefficient of variation (CV). CVs were calculated for each method over both seasons and locations, for each season over all locations, each location over all seasons, and for each season at each location. All heat unit summation methods had smaller coefficients of variation (CV) than the standard method of counting days from planting to first harvest. Heat unit summation methods improved harvest date prediction accuracy compared with the counting day method for tomatoes in the South Atlantic Coast (SAC) region. Prediction using location/season specific models were less variable than the models over all seasons and locations. Incorporating daylength improved model prediction accuracy when applied over all locations and seasons, all locations by season, and all seasons by location. Based on the results of this study, the heat unit summation technique recommended for this region (where the location and season specific models are not available) is the reduced ceiling method multiplied by daylength.

The effects of three rates of N, Mg, and B on cauliflower (Brassica oleracea, Botrytis group) yield, average curd mass, and hollow stem disorder were evaluated on sandy and clay loam soils. Cultivars White Empress and Stovepipe were tested on the sandy loam soil and `White Empress' was tested on the clay loam soil. Maximum mean curd mass and maximum yields were obtained with the highest N rates (269 and 381 kg·ha-1) applied to sandy loam and clay loam soils, respectively. Yield response to increased N rates varied with cultivar. Increasing Mg from 22.5 to 90 kg·ha-1 did not affect yield or curd mass on clay loam soil, but increased yield and mean curd mass on sandy loam soil. The Mg effect on curd mass was influenced by N and B rates. On both soil types, the higher Mg and B rates reduced the incidence of hollow stem, but the Mg effect was influenced by N applications. On clay loam soil, increasing B from 2.2 to 8.8 kg·ha-1 reduced hollow stem but had no effect on yield or curd mass. On sandy loam soil, B at 4.4 kg·ha-1 maximized yield and curd mass, but the hollow stem disorder continued to decrease as B rates were increased from 2.2 to 8.8 kg·ha-1.

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'.

Daily maximum and minimum air temperature, total solar radiation and daylength data from seven locations during three seasons of 3 years were used to compare 52 heat unit accumulation models with counting days as a harvest prediction method for pepper. The best model was defined as the one with the least variation, i.e. smallest coefficient of variation (CV). CV's were calculated for each method over all seasons and locations, for each method over all locations for each season, and for each method in each season at each location. In all cases heat unit accumulation methods were better than counting days. The location and season specific model was the most accurate, but the analysis over all seasons and locations did result in smaller CV's than counting days, so improved harvest prediction can be achieved by using regionally developed models.

The experiment screened two spring and two fall planting dates in six regions within North Carolina, South Carolina, and Georgia. The objective was to extend the production over the southeastern United States rather than at a single location. Spring harvests lasted from mid-April to early July. Summer-to-winter harvests lasted from mid-August to late January. Collards were not harvested in any of the locations from late January to mid-April or from early July to mid-August. More extensive planting dates may further increase the longevity of production.

Cucumber and potato crops were tested in a rotation with winter cover crops at different locations in Georgia, North Carolina, and South Carolina from 1991 to 1994. Biomass DM of vegetable crops was greatest when grown after crimson clover. Clover plantings resulted in a greater biomass than wheat when preceded spring cucumber crop. Vegetable biomass produced on clover plots or with N rates of 60 to 120 kg·ha–l was equivalent. Nitrogen recovery by cover and vegetable crops was enhanced by clover plantings. Clover biomass (tops only) provided an average of 138 kg N/ha for the cucumber crop, compared to an average of 64 kg N/ha provided by wheat. Nitrogen recovery by vegetable crops was also enhanced with 60–120 kg N/ha rates. Yields were highest when high N rates were used and when crops were produced on clover plots. Vegetable yield, cover crop biomass, and N recovery were positively correlated with vegetable biomass and applied N.

Pepper and sweet corn were tested in a rotation with crimson clover and velvet bean (Mucuna pruriens) cover crops at different locations in Georgia, North Carolina, and South Carolina from 1995 to 1996. Vegetable production with minimum-till following the cover crops was compared with two different conventional methods (following rye cover or fallow). All minimum-till/cover crop treatments caused reduction of total number of pepper fruit, compared to the conventional methods. Effects on premium grade (Fancy + U.S. #1) were similar to the effects on total fruit. The highest percentage of premium grade was produced by both conventional methods in 1996. Sweet corn responded similarly to these treatments in 1995. However, in 1996, clover plots had corn yields nearly as good as the conventional plots. As in bell pepper, plots with velvet bean cover produced lower yield in 1996. Treatment effects on number of marketable corn were the same as the effects on total ears produced.

Hank Kemble is the only county agent role ever cast in a network television series. On Green Acres, Mr. Kemble always had advice for novice farmer Oliver Douglas. Unfortunately, Mr. Kemble's advice was usually vague and uncertain. More unfortunate is that this is the only image many people have regarding Cooperative Extension. As the last segment of the land-grant system established, Extension personnel were the last recognized as equals among faculty. The mistaken image of the county agent as a book-trained farm boy with no common sense and a government job has been reinforced by declining respect for the farming community. In reality, county agents today deal with social and agricultural issues in urban and rural communities. Agents work with reduced staffs while being educators, scientists, and administrators in addition to routine duties. Extension specialists routinely teach and conduct research. National and international recognition and peer-reviewed publications are necessary for promotion while conducting traditional duties, too. As educational requirements of agents and specialists increased, numbers of undergraduates entering Extension dropped (

Bell pepper (Capsicum annuum) is traditionally transplanted either to the top of the root ball or to the cotyledons of the transplant. Recent evidence has shown that increased and earlier yields may be obtained by deeper transplanting of pepper. Thus, a study was undertaken to investigate the effects of pepper transplanting depth on flowering and the fruit characteristics of harvest fruit. Pepper was transplanted to the top of the rootball, the cotyledons, and the first true leaf at two locations in 1994. Both `Camelot' Hybrid and `Jupiter' (open-pollinated) cultivars were planted into bareground on Mar. 24 at Tifton, Ga. Only `Camelot' was transplanted into a plastic mulch with drip irrigation on Mar. 28 at Cool Springs. Plots consisted of a single row of seven plants with the internal five plants used for data collection. Treatments were replicated three times. Normal cultural and pest control practices were used at both locations. Data on flowering were collected 5 weeks after transplanting. Data on fruit characteristics were collected at harvest. Number of bloom clusters per plant, number of blooms per cluster, number of open blooms, and number of set blooms were significantly greater in the deeper-planted pepper at Cool Springs. The same was true for bloom clusters and blooms per cluster at Tifton. Number of blooms open and set were greater in deeper-planted `Camelot' at Tifton as well. There were virtually no differences among characteristics of harvest fruit. Earlier bloom set appears to occur in deeper-planted pepper on both bareground and mulched beds.

Bell pepper (Capsicum annuum) has traditionally been transplanted to the top of the root ball or to the cotyledons of the transplant. Recent studies have shown increased and earlier yields are obtained by transplanting pepper deeper. Thus, a study was initiated to investigate effects of transplanting depth on pepper yield and plant growth. Pepper was transplanted to the top of the rootball, the cotyledons, and the first true leaf in two locations in 1994. `Camelot' hybrid and `Jupiter' (open pollinated) cultivars were planted into bare ground on Mar. 24 in Tifton, Ga. Only `Camelot' was transplanted into a plastic mulch with drip irrigation on Mar. 28 in Cool Springs. Plots consisted of single rows of seven plants with data collected from the internal five plants. Treatments were replicated three times. Normal cultural and pest control practices were used at both locations. Plant measurement data were taken 5 weeks after transplanting. Yield data were collected at harvest. Total weight per plant of three harvests was significantly greater with peppers planted to cotyledons and first true leaf than those planted to the rootball in `Jupiter'. There was no significant effect of planting depth on `Camelot', although there was a distinct trend toward greater yield with deeper planting on plastic. The same trend was evident for average weight per plant and average number of fancy-grade peppers per plant. Average stem diameter, plant height, and length of largest leaf were all greater among deeper planted peppers. Deeper planting seems to have a positive effect on yield and plant growth, particularly with hybrid pepper planted into a plastic mulch.

A vegetable production system using winter cover crops and N rates was evaluated for several years in Georgia, South Carolina, and North Carolina. Snap bean, cucumber, tomato, potato, and sweetpotato crops were tested at different locations. Cover crop plots produced higher yields and better quality in all locations as seasons progressed over 4 years. Soil N levels in fallow, wheat, and clover plots were similar at initiation, but N gradually increased in clover plots in successive years. Yield and quality of root crops improved with Crimson clover without N applications compared to fallow plots with 60 kg N/ha. Effects on yield and tuber size are discussed. Nitrate and NH4-N in the soil profile from 15- to 150-cm depth were monitored at all locations. Nitrogen availability, depletion, and leaching below the root zone were determined. At low N rate, clover plots had slightly higher NO3 in the soil profile; however, at high N rate, N supply by clover was not as critical, and N leaching was detected at much lower depths than at low N rates.

During summer in southern Georgia, greenhouses often reach or exceed 49C. Subsequently, transplants grown in these houses tend to exceed optimum height. To determine effects of N and P fertility levels on pepper (Capsicum annuum) transplant growth, applications of nutrient solutions with 58, 12, and 0 ppm N and 114, 57, and 0 ppm P205 were applied to recently emerged Capistrano bell pepper beginning 12 Aug. 1994. Plants were grown in polystyrene flats using a commercial noncharged artificial soil mix. Nutrient solutions were applied as needed to maintain adequate moisture until 31 Aug., except for two treatments that received only water after 22 Aug. Data were taken on 22 and 31 Aug. With 58 ppm N, 0 P decreased plant height, leaf count, leaf area, and plant weight. Higher N increased plant height, ratings of intact root plugs and washed roots, stem diameter, leaf count, leaf area, and plant weight. At 12 ppm N, P had no significant effect on transplant growth. Withholding fertilizer the final week reduced plant height, ratings of intact root plugs, stem diameter, number of leaves, leaf area, and plant weight.

‘Champion’, ‘Georgia’, ‘Heavicrop’, and ‘Vates’ collards (Brassica oleracea L. var acephala) were planted in Fletcher and Lewiston, N.C.; Charleston, Clemson, and Florence, S.C.; and Attapulgus and Plains, Ga. to determine the most reliable method to predict harvest maturity based on temperature. Although cultivar differences existed within some of the planting dates, when pooled over all planting dates, cultivars yielded similarly within locations. Eight methods of calculating heat units from planting to harvest were applied to daily maximum and minimum air temperatures supplied from local weather bureaus for the spring and fall growing seasons from 1985 through 1987 in the three-state area. Coefficients of variation were used to determine which method was most reliable in predicting day of first harvest. The method with the lowest cv was to sum, over days for planting to harvest, the difference between the daily maximum and a base temperature of 13.4C; however, if the maximum was >23.9C, the base temperature was subtracted from an adjusted maximum equal to 23.9C minus the difference between the maximum and 23.9C. This method produced a cv of 9.1% compared to 11.4% for the standard method of summing the mean temperature minus the base of 4.4C over the entire growing season, or compared to 13.4% for counting days to harvest from planting.

Seedlings of sweet potato [Ipomoea batatas (L.)], which failed to form storage roots, produced good yields of sweet potato roots of acceptable size and grade when propagated asexually by vine cuttings.