The effects of amending soil with processed municipal waste (PMW), and the interaction of PMW with trenching, irrigation rates, and fertilizer rates on growth, and yield of tomato plants were tested. In a series of experiments, two rates of each of the following PMWs were incorporated into calcareous limestone soil: 1) Agrisoil (processed trash), 2) Daorganite (processed sewage sludge), 3) Eweson compost (processed trash and sludge), and 4) no PMW (control). In some experiments, secondary applications of PMW were applied to the beds at either a high rate, a low rate or not applied (control). There was no effect of secondary PMW applications on growth or yield. Generally, plants grown on trenched plots had greater growth and yield than plants on non-trenched plots. Plants grown in Daorganite had greater growth and yield than plants grown in the other PMWs. Plants in Daorganite tended to have higher photosynthelic and transpiration rates than plants in the other treatments. For all treatments, plants grown at one-half the standard fertilizer rate had less growth than plants receiving higher fertilizer rates. There was no interaction between irrigation rate and PMW for photosynthesis, growth, or yield. Plants grown in Daorganite had the greatest growth and tended to have greater yields, regardless of the fertilizer or irrigation rate. Processed trash composts (Agrisoil and Eweson) did not increase growth and yield, which may have been due to suboptimal application rates of these materials. Further studies are underway incorporating higher rates of these materials into the soil.
H. H. Bryan, B. Schaffer, and M. Ozores
Herbert H. Bryan and Yuncong Li
Cover crops have become an integral part of vegetable production practices in south Florida for weed control and retaining nutrients during the heavy summer rains. A wide variety of plants are used as cover crops in south Florida. Obviously, legumes contribute more nitrogen by fixing N compared to nonlegumes such as sorghum sudan grass, which is a common cover crop in this area. We have evaluated 10 cover crops, where six were legumes in 1997. In 1998, four cover crops (sunnhemp, sorghum sudan, sesbania, and aeschynomene) were evaluated. The sunnhemp (Crotalaria juncea L.) stands out from other tested cover crops for 2 years. Sunnhemp produced 8960 to 11,400 kg dry weight/ha and fixed up to 285 kg N/ha. The evaluation of effects of sunnhemp and other cover crops on the following tomato growth and yield are still in progress and will be discussed.
Monica Ozores-Hampton and Herbert H Bryan
Municipal solid waste compost was applied with a side delivery applicator on top of the bed as a mulch in May 1993, 6 months after transplanting at Homestead, Fla. Papaya (`Know You No 1') was grown with and without compost mulch. Compost was distributed on the surface of the bed ≈90 cm wide and 5 cm thick. There were no mulch effects on trunk diameter nor plant height. Plant height was affected by papaya sex 4 and 6 months after transplanting. Hermaphroditic plants were taller than female plants. There were no mulch effects on marketable yield per plant, marketable size, or number of cull fruit. Sex, however, influenced papaya size and total cull number. Hermaphroditic plants produced larger marketable fruit and more cull fruits than female plants. Lower plant mortality rates were found after 1.5 years in the mulched plants compared to unmulched plants. Soil and tissue analysis showed no differences in N, P, K, Mg, S, Mn, Fe, Cu, and B, except for Zn. Zinc contents in soil and tissue were higher in the mulched areas than unmulched areas.
M. Ozores-Hampton, B. Schaffer, and H. H. Bryan
The effects of amending soil with municipal soil waste (MSW) on growth, yield and heavy metal content of tomato were tested with different irrigation rates. The following MSW materials were incorporated into oolitic limestone soil: 1) Agrisoil compost (composted trash), 2) Daorganite compost (sewage sludge), 3) Eweson (composted trash and sewage sludge), and 4) no MSW (control). Two rates (high and low) were applied to the soil for each compost. There were no significant effects of irrigation rate on any of the variables tested for tomato in 1991 or 1992. Therefore, the lowest irrigation rate appeared to be adequate for optimum tomato production. Plants grown in Daorganite at the lowest rate of 8 t/ha had greater growth and yield than plants grown in the other MSW materials or the control. Agrisoil and Eweson composts did not increase growth or yield, which may have been due to suboptimal application rates of these materials. There were no differences in the concentration of heavy metals in fruit or leaves among MSW materials or rates. MSW rate generally had no effect on root heavy metal concentration, except for Eweson where the high rate resulted in a higher root zinc concentration than the low rate. There were signifant differences in root concentrations of lead, zinc, and copper among MSW materials. Leaf concentrations of all heavy metals tested were within normal ranges for tomato.
N.E. Roe, S.R. Kostewicz, and H.H. Bryan
Several companies and government agencies are now making municipal solid waste (MSW) composts. This study was undertaken to test effects of a MSW compost with different rates of fertilizer on broccoli. Treatments were compost at 0, 6.7, 13.5 and 26.9 MT/ha and fertilizer at 84 and 168 kg/ha N on a, fine sand soil. Treatments were applied, rototilled, and beds formed and covered with black plastic. Broccoli cv. `Southern Comet' transplants were set on March 2 with 46 cm between plants, 2 rows/bed, and beds centered at 1.8 m. Mature heads 15 cm and larger were harvested on April 25. Numbers of heads and total weight of heads were recorded and average head weights were calculated. Data analysis indicated main effect significance for fertilizer rate but not for compost rate with no interactions. The 168 kg/ha level of N resulted in a yield of 5795 kg/ha while the 84 kg/ha level produced 3849 kg/ha. Average head weights were 264, 262, 257, and 252 g; and marketable yield were 5.0, 4.8, 5.0, and 4.5 MT/ha; at 0, 6.7, 13.5, and 26.9 MT/ha, respectively.
Nancy E. Roe, Peter J. Stoffella, and Herbert H. Bryan
A mulch of municipal solid waste compost at 224 t·ha was compared with glyphosate sprays and a nontreated check for weed control in vegetable crop bed alleys during Spring and Summer 1992. In both experiments, there was a significantly lower percentage of weed coverage in the compost mulch and herbicide spray plots than in the control plots. Weed control in the compost and herbicide treatments was similar. In the spring experiment, tractor tire traffic through the alleys reduced weed growth in all plots by 62 % and 44% at 16 and 73 days after treatment initiation, respectively. These results suggest that municipal solid waste compost may have potential as a viable mulch for weed control in vegetable crop alleys. Chemical name used: isopropylamine salt of N -(phosphonomethyl) glycine (glyphosate).
Gladis M. Zinati, Herbert H. Bryan, and Yuncong Li
Using herbs for medicinal purposes, ornamentals, and landscape plantings has increased significantly. Propagating from seeds is considered the most-efficient method of producing medicinal plants for commercial production. Among the herb seeds the purple coneflower (Echinacea angustifolia) was found difficult to germinate. Laboratory studies were conducted to: 1) determine optimum temperature from a temperature range 15 to 30 °C for seed germination; 2) determine effects of 5 10, 20, and 30 days of stratification at 5 and 10 °C in darkness on germination; and 3) determine effects of priming in the dark for 1, 3, 6, and 9 days with 0.1 M KNO3 and biostimulants at optimum temperature to enhance early emergence and final germination. Germination was enhanced from 45% in untreated seeds to 81% in seeds treated with either 50 ppm GA4/7 or 100 ppm ethephon at 24 °C. Final germination was 81% under daylight conditions when seeds were stratified in dark at 10 °C for 30 days over nonstratified seeds (13%). Priming seeds in 0.1 M KNO3 for 3 days significantly enhanced early germination to 70% with 100 and 150 ppm ethephon and final percent germination of 88% with either 100 ppm ethephon or 150 ppm GA4/7, while untreated control seeds resulted in 31% for same period of priming.
Jonathan R. Schultheis, Daniel J. Cantliffe, and Herbert H. Bryan
Early plant growth, root quality, and yield from sweetpotato plants obtained from zygotic seed, somatic embryos, or cloned from stock plants (through micropropagation, rooted node explants, or nonrooted terminal vine cuttings) were compared in field plantings established in 1986, 1987, and 1988 in Gainesville and/or Homestead, Fla. At planting, transplants derived from somatic embryos had more nodes than the other propagules, while vine length per plant was greatest with nonrooted vine cuttings obtained from stock plants. The number of nodes (up to 253%) and vine growth (up to 517%) were greater when plants were derived from stock plants and zygotic embryos than from somatic embryos 4 weeks (1987) and 6 weeks (1988) after planting. Vegetative growth, larger-sized storage roots (>6 cm in diameter), and total yields (all root grades combined) were consistently reduced when plants were derived from somatic embryos compared with propagules of stock plant origin. Plants obtained from somatic embryos required more time for roots to bulk or size than the other propagule types. Root yield from plantlets derived from somatic embryos showed a 14-fold increase when harvest was delayed at least 53 more days. Root weight, regardless of harvest date, was greater when plants were derived from stock plants rather than from somatic embryos, while in most cases plants derived from somatic embryos yielded a greater number of roots than from stock plants. Plants obtained through somatic embryony and harvested at a later date typically had yields exceed 1.8 kg per plant. Morphology of plants obtained from somatic embryos was uniform and identical to plants derived from stock plants.
Nancy E. Roe, Peter J. Stoffella, and Herbert H. Bryan
Increasing disposal problems with polyethylene (PL) mulch and greater availability of compost prompted an investigation into the effects of using compost as a mulch on horizontal raised bed surfaces with living mulches (LMs) on vertical surfaces. Wood chips (WC), sewage sludge-yard trimming (SY) compost, and municipal solid waste (MW) compost were applied at 224 t·ha-1 on bed surfaces. Sod strips of `Jade' (JD) or `Floratam' (FT) St. Augustinegrass (Stenotaphrum secundatum Kuntze) or perennial peanut (Arachis glabrata Benth.) (PP) or seeds of a small, seed-propagated forage peanut (Arachis sp.) (SP) were established on the vertical sides of the raised beds before transplanting bell pepper (Capsicum annuum L.) into the beds. Phytophthora capsici reduced pepper plant stand in PL-mulched plots compared with organic mulch (OM) and LM. Despite the stand reduction, total pepper yields were highest in PL plots and, in the OM plots, decreased in the order SY > MW > WC. Early fruit yields and yield per plant were highest from plants in PL plots followed by SY. Among LMs, plants in SP plots produced highest early yields and FT produced the lowest. Plants in PL plots produced the largest fruit. When the same plots were seeded with winter (butternut) squash (Cucurbita pepo L.), plant stands were higher in MW than WC and SY. Squash yields were similar between PL and OM plots.
H.H. Bryan, A.A. Abdul-Baki, L. Carrera, G. Zinati, and W. Klassen
Ground covers in orchards and living mulches in vegetable fields can be effective in reducing weed control costs and loss of water and nutrients from the soil, fixing N, and adding organic matter to the soil. Several accessions of rhizoma (perennial) peanut were evaluated in 1999, 30 months after planting, at the farm of the Tropical Research and Education Center, Univ. of Florida, Homestead, in gravelly, calcareous soil with a pH of 7.5. Evaluation criteria included adaptability (plant vigor, rhizome growth, and biomass yield), weed suppression, N-fixation, nutrient content, leaf density, and Fe chlorosis. Accessions that survived exhibited major differences in the evaluation criteria. Accessions No. 6968 and 4222 (recently named `Amarillo') showed promising potential for use as ground cover and a living mulch in vegetable fields in southern Florida.