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.
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.
The rooting substances of tomato (Lycopersicon esculentum Mill.) explants during root regeneration were studied. The root-promoting substances of the basic, acidic, and bound ether-soluble fractions of the plant extracts after paper chromatography were determined by a tomato hypocotyl test. The basic root-promoting substances in the basal hypocotyl region changed qualitatively, while those of the acidic and bound fractions decreased with rooting. It was found that in 5-day-old explants, the highest root-promoting substances were in the bound fraction, and in the basal hypocotyl region. Histological evidence showed the presence of preformed root primordia in the rooting region of 10-day-old tomato explants.
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.
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.
The effects of municipal solid waste (MSW) materials on growth, yield, and mineral element concentrations in tomato (Lycopersicon esculentum Mill.) (1991 and 1992) and squash (Cucurbita maxima Duch. Ex Lam.) (1992 and 1993) were evaluated. Agrisoil compost (composted trash), Eweson compost (co-composted trash and sewage sludge), or Daorganite sludge (chemically and heat-treated sewage sludge) were incorporated into calcareous limestone soil of southern Florida. The control had no MSW material added to the soil. The effect of MSW on crop growth, yield, and mineral element concentrations varied considerably between years for tomato and squash. In 1991, tomato plants grown in soil amended with Eweson or Daorganite had a greater canopy volume than plants in the control treatment. Tomato plants grown in Daorganite had greater total fruit weight (1991) than plants in Agrisoil and more marketable fruit (1992) than control plants. In both years, tomato plants in Agrisoil had higher root Zn concentrations than plants in the other treatments. In 1992, tomato plants in Eweson had lower root Mn concentrations than plants in the other treatments, whereas Mg concentrations in the roots were higher in the Daorganite treatment than in Eweson. Tomato plants in Agrisoil had higher Pb concentrations in the roots than plants in all other treatments. In 1991, leaves of tomato plants in Agrisoil had lower Ca concentrations than leaves of plants in the control treatment. In 1992, leaf Zn concentrations were greater for tomato and squash in Agrisoil than in the control or Daorganite. In 1992, canopy volume and yield of squash were greater for plants in Daorganite than for plants in the control and other MSW treatments. Although canopy volume and total squash fruit weight did not differ among treatments in 1993, plant height was greater for squash plants in the MSW treatments than for those in the control. In 1993, leaf Mg concentrations were greater for squash grown in Daorganite than for plants in the control or Agrisoil. In 1993, fruit Cd concentration was higher for plants with Eweson than for plants in the control or Agrisoil. However, the fruit Cd concentration in squash grown in Eweson compost (1.0 mg/kg dry weight) was far below a hazardous level for human consumption. Our results indicate that amending calcareous soils with MSW materials can increase growth and yield of tomato and squash with negligible increases in heavy metal concentrations in fruit.
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.
Bell peppers (Capsicum annuum L. cv. Early Calwonder) were plug-mix seeded at 13-, 25-, 38-, and 51-cm within-row spacings in two rows on raised beds and thinned to one, two, or three plants per hill upon emergence. The experiments were conducted on commercial pepper fields located in southern Florida during the Winter 1983 and Spring 1984 seasons. Populations ranged from 21,527 to 258,328 plants/ha. Plant growth characteristics were measured at anthesis and just before the final harvest in each experiment. Root and shoot weights, shoot : root ratios, and stem diameters generally decreased and plant heights generally increased in response to higher plant populations. The lower shoot : root ratios at higher plant populations indicated that plants were producing more root mass in proportion to shoot mass than plants at lower populations. Number of primary and secondary branches per plant in the two experiments averaged 2.7 and 5.3, respectively, and were generally not influenced by plant populations. Marketable fruit yields/ha increased linearly in response to higher plant populations. Marketable fruit number and weight per plant decreased with higher plant populations, whereas fruit size (g/fruit) was unaffected. This observation suggested that the higher marketable yields/ha at higher plant populations were attributed to more plants with a lower number of similarly sized fruits per plant. The 25-cm within-row spacing with two plants per hill resulted in 81,109 plants/ha, the optimum marketable pepper fruit yield.