Colored plastic mulches were evaluated for their effect on the production of a triploid (`Honeyheart') and a diploid (`Sangria') watermelon cultivar during the spring growing season. Colored mulches affected cucumber beetle populations; the SRM-Red (Selective Reflective Mulch) and yellow plastic mulch plots had among the highest cucumber beetle populations recorded in both cultivars while the silver-reflective and the silver-on-black plastic mulches had among the lowest. In general, most mulched plots had longer vines than the bare-ground treatment, with few differences in vine length among treatments by 4 weeks. There were no differences among mulch treatments in first and total `Honeyheart' harvest while the IRT-100 (infrared transmitting; green), PST (photosynthetic reduced transmitting), and silver-on-black plastic mulches had the highest first `Sangria' harvest and among the highest total `Sangria' harvest. Plants in plastic mulch treatments had higher yields as a result of higher fruit number per area. Fruit weight, length, and diameter and total soluble solids for both cultivars were not affected by colored plastic mulch treatments.
Cucumber (Cucumis sativus L.) and squash (Cucurbita pepo L.) were grown in a replicated trial on three types of plastic mulch: solid black plastic mulch, solid aluminum-coated plastic mulch with a silver reflective appearance, and black plastic mulch with two aluminum-coated strips attached. Striped cucumber beetle (Acalymma vittata Fabricius) and spotted cucumber beetle (Diabrotica undecimpunctata howardi Barber) (Coleoptera: Chrysomelidae) counts on yellow sticky cards were obtained over eight weekly samplings. For cucumber, on the peak beetle population date, there were six times as many striped cucumber beetles in solid black plastic mulch as in aluminum-coated plastic mulch, and nearly three times as many as in black plastic mulch with aluminum strips. For squash, both striped and spotted cucumber beetle counts were significantly higher on solid black plastic mulch on three peak sampling dates than on aluminum-coated plastic mulch and black plastic mulch with aluminum strips, with counts 4.9 to 5.5 times higher in solid black plastic mulch than in aluminum-coated plastic mulch, and 2.2 to 2.6 times higher than in black plastic mulch with aluminum strips. Using a threshold of 15 beetles/sticky card, no insecticidal applications were needed on solid aluminum-coated mulch, while an average of 1.8 insecticidal applications were needed on solid black plastic mulch, and 0.8 insecticidal applications on black plastic mulch with aluminum strips. The cost of solid black plastic mulch and its insecticidal applications, $186/acre ($459/ha), was $102/acre ($252/ha) less than the cost of aluminum-coated plastic mulch without insecticidal application, $288/acre ($711/ha). However, squash fruit from plants grown on aluminum-coated plastic mulch could be direct marketed as pesticide-free, at a price 25% higher than fruit on which pesticide had been applied. For an average yield in Virginia of 600 boxes/acre (1,482 boxes/ha) [20 lb/box (9 kg/box)] of squash, this translates to a $1,200/acre ($2,964/ha) increase in revenue. Yield on aluminum-coated plastic mulch was delayed by one week, but there were no significant differences in cumulative yield over 14 harvests.
Commercially available polyethylene mulches were evaluated for their influence on spectral properties (absorption, reflection, and transmission) and soil temperature during the growing season. Vegetative growth and yield of bell pepper (Capsicum annuum cv. Keystone Resistant Giant No. 3) plants were evaluated for each mulch. Black plastic had the greatest absorption (95%) of photosynthetic photon flux (PPF; 400-700 nm). White plastic had the greatest reflection (6575%) of PPF and blue (400-500 nm) light. The Alor selective mulch had the greatest reflective far-red/red ratio (730-740/640-650 nm) of light. Clear plastic had the greatest transmission (90%) of PPF and blue light. Soil temperature was coolest under the white mulch (32 C) and warmest under the clear mulch (52 C) when measured at maximum soil temperature in the early afternoon (1400 to 1800 hrs). Vegetative growth and yield were greatest for plants grown on the white mulch treatment and lowest for plants grown on the clear mulch treatment.
Field studies were conducted for three seasons, Fall 1994, Spring 1995, and Fall 1995 on the effect of UV-reflective films (mulches) on fruit yields and on the silverleaf whitefly [Bemisia argentifolii (Bellows and Perring)] of staked, fresh-market tomatoes (Lycopersicon esculentum Mill). The UV-reflective mulches were metallized aluminum (ALU) and painted aluminum (PAL) on either black or white plastic film. The AL and SL mulches were evaluated with and without a white (fall) or black (spring) 25-cm-wide painted band in the bed center. Controls were the conventional white (fall) or black (spring) polyethylene mulches. Highest reflected energy (μmol·m–2·s–1) to the plants at 25 cm from the mulch surface was measured on the ALU without white painted band or on PAL on white or black mulch with white painted band. Lowest energy was reflected from the white or black controls. Whitefly populations in the fall were lower on the ALU than on the PAL mulches. In the spring, when whitefly populations were low, number of whiteflies on tomato leaves were similar with all treatments. The proportion of plants with symptoms of the silverleaf whitefly transmitted tomato mottle virus (TMoV) were highest on controls. Yields in the fall were similar with UV-reflective or with white mulch. In the spring, fruit size and marketable yields were greater (P < 0.05) on plants with PAL on white plastic film without black band than on black control.
We thank Vacumet Corp., Wayne, N.J., and Polygro Plastics, Agandilla, Puerto Rico, for supplying the plastic films for this project. Florida Agricultural Experiment Station journal Series No. R-05998. The cost of publishing this paper was
Abstract
Field studies were conducted in 1973 and 1974 to determine the effects of various reflective film mulches, vegetal barriers of millet (Pennisetum americanum (L.) K. Schum), and soil- and foliar-applied pesticides on yields and control of the watermelon virus complex (WMV), insects, nematodes, and soil-borne pathogens affecting yellow summer squash (Cucurbita pepo var melopepo L. Alefi, ‘Dixie’). All film mulches used (aluminum; white and blue plastic; brown paper) significantly reduced WMV in both fruits and plants. The millet barrier caused a significant reduction in WMV infected plants. In 1974, the systemic insecticide, carbofuran (Furadan) and/or sprays of mineral oil, significantly reduced WMV in non-mulched plots. Brown paper mulch significantly increased infestation of pickleworms, Diaphania nitidalis (Stoll) and all mulches significantly reduced infestations of serpentine leafminers, Liriomyza munda Frick. Leafminers were also controlled with carbofuran. Film mulches had no significant effect on populations of plant-parasitic nematodes and plant-pathogenic fungi. Both groups of pests were controlled with DD-MENCS (a mixture of 1,3-dichloropropene, 1,3-dichloropropane, methylisothiocyanate), but not with carbofuran or sodium azide. Film mulch increased squash yield 70 to 610% over the unmulched control. Plants in non-fumigated plots covered with aluminum and white plastic mulches produced significantly greater yields than plants in plots covered with blue plastic and brown paper mulches. Soil pesticides significantly increased yields over the non-fumigated control, and, averaged across main plots, DD-MENCS = DD-MENCS + carbofuran > carbofuran + sodium azide > sodium azide = nontreated check. The effects of film mulch were greatest in the non-fumigated check. Conversely, the effects of soil fumigation were negligible under film mulch and one could be substituted for the other.
tomato seeds; United Irrigation and Roberts Irrigation Products Inc., for drip tape; Hydro Agri North America, Inc., for calcium nitrate liquid fertilizer; and Green-Tek and Sonoco for plastic film mulches. Mention of trade names in this publication does
Pest control-related problems jeopardize the advancement of our nation's vegetable industry. Because of the adverse effects of many fumigants. the grower is increasingly pressured to utilize sustainable. environmentally sound agricultural practices yet still maintain a marketable, blemish-free product.
The effects of wavelength selective mulches and three different fumigants on overall plant development and nematode control were studied in field grown, staked tomatoes. Plots were fumigated with methyl bromide. Telone II, or Telone C17. Within rows, mulch color was established by application of either white or red exterior enamel paint to the black plastic surface of polyethylene mulch. Reflective light from each mulch color was measured using a LiCor 1800 Spectroradiometer. Temperature below the mulch surface was monitored with a datalogger.
Prior to the first marketable harvest, plants grown on white mulch produced greater fruit weight and total dry weight than plants grown on black or red mulch. Total marketable yields, however. were not significantly different between the three mulches. Early and marketable yields from fumigated plots did not differ from control treatments. The lack of response due to fumigation may have been due to low initial nematode populations in the field.
The small, B size potatoes (<2 inches but ≥1.25 inches in diameter) represent a keen interest in new, specialty food items. Exotic shapes and color shades of the specialty varieties are also known for intense flavors and variations in textures in firmness and fiber that consumers are looking for today in an ever increasing health consciousness among consumers. In 2006, the varieties `French Fingerling' (West Edmonton, Alberta, Canada), Villetta Rose (Univ. of Wisconsin) and B1145-2 (USDA, Beltsville, Md.) were planted in a double row 8 inches between tubers and 18 inches between rows in a replicated trial using colored mulches. The mulch color included red, white, black, blue, green, and silver foil. These plastic mulches were laid on 6-ft centers. The mulches were shown to affect the microclimate of soil temperature, as expected, and therefore affecting yield. These temperature differences were measured with a Campbell CR 10X weather station (Logan, Utah) probes at a 2 inches above the soil surface and 4 and 6 inches below the soil surface. Plant stands were excellent with all mulches, however, blue mulch caused early emergence while white and silver delayed emergence. Just the opposite effect happened when it came to yields. The highest individual tubers per plant came from the white mulch with the green having the lowest tuber yields. Cultivar differences were also seen in there ability to produce marketable tubers. `Villetta Rose' had the highest plant vigor and also the most marketable tubers per plant. B1145-2 produced most of its tubers >2 inches in diameter with the tubers nonuniform in shape. French Fingerling produced a very uniform oblong tuber with few defects. Yields and quality were above normal for all cultivars when grown on either the silver reflective mulch or the white mulch.
compared reflective mulch films to the standard black plastic mulch for subtropical strawberry production. Perhaps most notably, Albregts and Chandler (1993) found entirely white- and yellow-painted mulch films to improve early-season yields compared with