Two cultivars of onions, `New Mexico Yellow Grano' and `Midstar' were seeded in single bed plots in mid-October 1985 and 1987 for overwinter transplant production. Plots were covered with spunbonded polyester (POL) or tunnels of clear polyethylene (CLR) or microperforated polyethylene (PER) (1985 only) in early November and compared to uncovered controls. Temperatures were monitored 5 cm above the soil surface under the covers in each plot with three parallel-wired thermocouples. Heat unit (HU) accumulation (number of degrees by which the daily mean temp exceeded 0°C) was recorded for each plot and compared with onion plant size. HU accumulation by mid-February 1986 under CLR, POL and PER was 139%, 131% and 113%, respectively, of that over bare ground. In mid-March 1988 cumulative HU under CLR and POL were 192% and 125% of those over bare ground. Plant diameter varied with variety but increased linearly with cumulative HU for all varieties. `New Mexico Yellow Grano' reached the minimum 4 mm size for transplanting at about 1800 HU while `Midstar' required only 1500 HU. CLR produced useable transplants by early March and the other covers by late March. Numbers of useable transplants per meter of bed in mid-March ranged from 3-6 in uncovered plots to 102-153 under PER tunnels, 185-203 under POL and 263-301 under CLR tunnels. CLR tunnels appear to provide sufficient HU accumulation to produce onion plants for transplanting in early March in West Texas.
Charles S. Vavrina and George Hochmuth
`Allstar” tomatoes raised from seed in Todd™ containerized transplant trays were treated with 1/4 strength Hoagland's solution modified to supply 0, 15, 30, 45, 60, or 75 mg·l-1 N daily. Nutrient application was achieved via ebb and flow irrigation. N was supplied as ammonium nitrate. Tissue sample values for elements tested, excluding N, were essentially adequate for all treatments at transplanting (6 weeks after seeding). Visible transplant differences in the plant house did not translate to significant yield differences in the field when rates of 30 mg·l-1 or greater were used in either spring or fall plantings in FL. A similar trial shipped to PA showed that 75 mg·l-1 in the plant house resulted in the greatest early field yields, but 45 mg·l-1 produced the greatest overall yield.
Ray E. Worley
Soil amendments of complete fertilizer, manure and limestone added to backfill soil at transplanting did not influence pecan tree appearance or growth. Removal of ⅓ or ½ of the top at transplanting was compared with no top removal. Removal of ½ the top improved tree vigor the first year but differences in vigor and growth had dissipated by the second year. With 60 cm diameter holes, vigor and growth increased as depth increased from 30 to 90 cm. Trees planted in a 20 cm diameter post hole had poorer vigor and growth the first two years than trees planted in 60 cm diameter × 90 cm depth hole. Differences in vigor and growth due to hole size also dissipated with time and were not significant at the end of the third year. Pecan trees apparently are resilient and can overcome a poor transplanting job.
Ricky D. Kemery and Michael N. Dana
Fir seedling transplant containers were used as an alternative to conventional plug containers (72 per tray) in a system to grow seedlings of native prairie perennials and install them on a highway site in central Indiana. Plants grown in deep-tube fir-seedling containers exhibited greater fresh and dry weights than conventional plug transplants with no root circling. Results from survival data indicate that plants grown in fir seedling containers offer better chances of success on highway sites with low soil fertility and poor soil structure. A chronology of installation methods, tools, and mechanization possibilities is presented.
David O. Cliffe
Transplant production utilizing cell containers has been practiced commercially in Australia for fifteen years, with Todd flats the predominant type in use. Many methods of transplant production have evolved in Australia which due to its unique climate and the needs of the horticultural industry, which grow a diverse range of crops throughout the year. Current growing practices include nutrient programs, pre-shipping treatments, and methods of transporting plants over long distances. Current production costings will be discussed. A number of areas will be discussed that warrant more research to reduce costs and also expand the concept of cell production to encompass a wider range of plant species.
Puffy Soundy, Daniel J. Cantliffe, George J. Hochmuth, and Peter J. Stoffella
Lettuce (Lactuca sativa L.) `South Bay' transplant growth and development were evaluated at 0, 30, 60, 90, and 120 mg·L–1 N fertigated at frequencies of every 1, 2, 3, or 4 days in a floatation production system to produce plants with optimum roots and shoots which easily pull from trays. Greenhouse experiments (four) were conducted to evaluate root and shoot weight, percent transplant pulling success, and leaf N content, 28 days after sowing (DAS). Field trials, using transplants produced in Greenhouse experiments 2 and 4, were conducted to evaluated subsequent yield, head quality characteristics, and leaf N content. Generally, as N concentrations increased, dry shoot weight and leaf N concentration increased, and root:shoot ratios decreased linearly or quadratically. Lettuce transplants grown in a floatation irrigation system fertigated every second to third day with 60 to 90 mg·L–1 N resulted in transplants with optimum root systems to achieve the highest pulling success rate from flats. Subsequent yields and head quality were optimum for pretransplant production fertigation N concentration of 60 to 90 mg·L–1, regardless of irrigation frequency.
Winston Dunwell, Dwight Wolfe, William Maksymowicz, and Darrell Slone
Alternative use for float system greenhouse space is being studied in Kentucky. High sugar sweet corn (Zea mays L.) cultivars direct seeded into cool soils germinate poorly. A float transplant production system was used to produce high sugar sweet corn transplants that could be planted into cool soils. 100 seeds of sugar enhanced (se) 'How Sweet It Is' and super sweet (sh2) 'Early Xtra Sweet' sweet corn cultivars wars seeded into trays with a cell size of either 19 or 49 ml/cell. The trays were floated on heated or unheated water in the greenhouse. Percent germination was significantly influencedby cultivar. A greater percent germination was observed for 'How Sweet It Is' compared to 'Early Xtra Sweet' and for seeds sown in the 49 ml/cell trays compared to the 19 ml/cell trays. No significant differences resulted from varying the water temperature. Transplants were planted into cool soils with direct seeded sweet corn on April 21, 1992. The use of transplants resulted in a significantly greater plant stand and a two week earlier harvest than the use of the direct seeding.
Bizhen Hu, Mark A. Bennett, and Matthew D. Kleinhenz
. 2012 Microclimate modification using eco-friendly nets for high-quality tomato transplant production by small-scale farmers in east Africa HortTechnology 22 292 298 Hernández-Herrera, R.M. Santacruz-Ruvalcaba, F. Ruiz-López, M.A. Norrie, J. Hernández
Jim E. Wyatt, Marla C. Akridse, and Douglas W. Hamilton
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.
Darbie M. Granberry and William Terry Kelly
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.