Reflective Plastic Mulch Research Articles

Use of Insect Exclusion Row Cover and Reflective Silver Plastic Mulching to Manage Whitefly in Zucchini Production.

The challenges that sweet potato whitefly (Bemisia tabaci) creates for vegetable production have increased in the southeastern U.S. Growers must use intensive insecticide spray programs to suppress extremely high populations during the fall growing season. Thus, the objective of this study was to evaluate the use of a reflective plastic mulch and an insect row cover as alternative methods to the current grower practices to manage whiteflies in zucchini (Cucurbita pepo) production. Field experiments were conducted with a two-level factorial experimental design of cover and plastic mulch treatments arranged in a randomized complete block design, with four replications in Georgia in 2020 and 2021, and in Alabama in 2021. Cover treatments consisted of an insect row cover installed on zucchini beds at transplanting and removed at flowering and a no-cover treatment, while plastic mulch treatments consisted of reflective silver plastic mulching and white plastic mulching. During all growing seasons, weather conditions were monitored, whitefly populations were sampled weekly, zucchini biomass accumulation was measured at five stages of crop development, and fruit yield was determined at harvesting. Warm and dry weather conditions early in the growing season resulted in increased whitefly populations, regardless of location and year. In general, the reflective silver plastic mulching reduced whitefly populations compared to the conventional white plastic by 87% in Georgia in 2020, 33% in Georgia in 2021, and 30% in Alabama in 2021. The insect row cover treatment reduced whitefly populations to zero until its removal. Consequently, zucchini plants grown with the insect row cover and reflective silver plastic mulching had an increased rate of biomass accumulation due to the lower insect pressure in all locations. Zucchini grown using silver reflective plastic mulch and row covers had an overall increase of 17% and 14% in total yield compared to white plastic mulch and no-cover treatments, respectively. Significant differences in yield among locations were likely due to severe whitefly pressure early in the fall season, and total yields in Georgia in 2020 (11,451 kg ha-1) were 25% lower than in Georgia in 2021 (15,177 kg ha-1) and in Alabama in 2021 (15,248 kg ha-1). In conclusion, silver plastic mulching and row covers reduced the whitefly population and increased biomass accumulation and total yield. These treatments can be considered ready-to-use integrated pest management practices for growers.

Integrated Effect of Plastic Mulches and Biorational Insecticides in Managing Tomato Chlorotic Spot Virus (TCSV) and Its Vector Thrips in Tomatoes.

In the USA, tomato chlorotic spot virus (TCSV) was first identified in Miami-Dade County of Florida in 2012. This viral disease is transmitted by thrips (Thysanoptera: Thripidae) of different species, imposing a serious threat to the entire tomato production in the state. Both cultural and chemical control techniques could be essential tools to combat this vector-borne disease. In the present two-year-long study, we determined the effect of different types of plastic mulches and biorational insecticides on managing thrips and TCSV. Results from the leaf and flower samples showed a significantly lower adult thrips population in Entrust®SC treated tomatoes than in other treated and untreated tomatoes in 2018. Silver on black and silver on white reflective plastic mulches significantly reduced the adult thrips population in 2018. In both study years, marketable yield was significantly higher in tomatoes treated with Entrust®SC and reflective plastic mulches than in other treatments. The incidence of TCSV was significantly reduced in tomatoes treated with Entrust®SC and reflective plastic mulches than the untreated control in 2018. Marketable yield was negatively correlated with the thrips population, as observed from the Pearson correlation coefficient analysis. This research describes a potentially viable management program for thrips and thrips-transmitted TCSV.

Integrated approach using insecticides in combination with reflective plastic mulch for the management of pepper weevil, Anthonomus eugenii (Coleoptera: Curculionidae).

Pepper weevil, Anthonomus eugenii Cano, is a serious pest of peppers (Capsicum annuum) in the United States and worldwide. This study evaluated the combined effect of insecticides (thiamethoxam and oxamyl) and reflective mulches (reflective silver on white and reflective silver on black) on pepper weevil suppression and yield increase. This study was conducted under field conditions in Homestead, FL, during the fall 2020, spring 2021, and 2022 growing seasons. The study consists of 2 mulch treatments as the main plots (reflective "silver on white," "white on black") and a bare ground with "no mulch" treatment in fall 2020 and spring 2021, and in spring 2022 with an additional treatment of reflective "silver on black" mulch. We hypothesized that jalapeño pepper grown on either reflective "silver on black" or "silver on white" plastic mulches would have fewer pepper weevil adults, fewer pepper weevil infested fruits, and higher yield than those grown on "white on black" plastic mulch or bare soil. Overall, the number of pepper weevil adults on plants and infested fruits was lower in the fall season compared to the spring season. In the fall 2020 season, the number of adults was not significantly different regardless of insecticide treatment and mulch type. However, infested fruits were higher on the untreated control plots than the treated plots in Fall 2020. Marketable yield was not significantly different among insecticide treatment on the "white on black" and reflective "silver on white" mulches. However, thiamethoxam treated plots had significantly higher yield than on the rest of the treatment on the bare soil with "no mulch." The number of adults was higher in the untreated control plot than the treated plots in spring 2021. The number of infested fallen fruits was not significantly different. However, marketable yield was significantly different among treatments on the "white on black" and reflective "silver on white" mulches in 2021. The treated plots on the reflective "silver on white" mulch produced significantly higher yield than the untreated control plots in 2022. The result of this study suggests that growing jalapeño peppers on reflective plastic mulch ("silver on white") in integration with thiamethoxam or oxamyl has the potential in reducing pepper weevil adult population and increasing yield of jalapeño pepper.

Integrated Pest Management Programs for Pear Psylla, Cacopsylla pyricola (Förster) (Hemiptera: Psyllidae), Using Kaolin Clay and Reflective Plastic Mulch.

Pear psylla, Cacopsylla pyricola (Förster) (Hemiptera: Psyllidae), is the most economically important pest of pears grown in Washington State. Standard conventional management programs involve season-long broad-spectrum insecticide sprays. Although the industry uses some tools that are not disruptive to biological control, such as kaolin clay and selective insecticides, they are additions to broad-spectrum insecticides instead of replacements. Conventional sprays suppress pear psylla through the spring and early summer; however, disruption of biological control leads to pear psylla outbreaks near harvest. In 2018 and 2019, we tested two season-long programs that used only selective approaches. The programs began with either kaolin clay or reflective plastic mulch and were followed by identical spray programs using only selective insecticides. Programs were compared with an industry standard conventional program that used numerous broad-spectrum insecticides throughout the season, and a check program with no insecticides for pear psylla. Experiments were conducted using replicated 40-tree plots in a research orchard near Wenatchee, WA with high pear psylla pressure. In both years, selective programs had similar pear psylla densities to the industry standard program and all had lower pear psylla densities and fruit injury than the check. Both selective programs had lower fruit injury than the industry standard in the first year, and similar injury to the industry standard in the second year. Our results suggest kaolin clay and reflective mulch can effectively suppress pear psylla populations and injury in the early season and support season-long selective management programs without the use of broad-spectrum insecticides.

Effect of Plastic Mulch Colors on Anasa tristis (Hemiptera: Coreidae) Population Dynamics in Summer Squash, Cucurbita pepo (Cucurbitales: Cucurbitaceae).

The squash bug, Anasa tristis (De Geer), is a serious pest of cucurbit crops across the United States, especially within summer squash (Cucurbita pepo L.) systems. Using their piercing sucking mouthparts, squash bugs feed on both leaf tissue and fruits, often leading to leaf necrosis, marketable fruit loss, and even plant death. To date, the relationship between squash bug presence and plasticulture has not been adequately investigated. This 2-yr study evaluated the effects of white, black, and reflective plastic mulch colors on the occurrence of all squash bug life stages and marketable zucchini yield in Virginia. In both years, A. tristis adults and egg masses were more numerous on zucchini plants grown in white and reflective plastic mulch compared to bare ground plants. Greater nymphal densities and marketable fruit yield were observed in certain plastic mulch treatments versus the bare ground treatment, yet these differences were not consistent in both years. Contrary to the repellency effects reflective mulches have on other cucurbit insect pests, our research suggests that reflective and other plastic mulch colors can negatively impact squash bug management, especially in regions with high A. tristis pressure. Our study offers new insights for cucurbit growers to use when considering whether they should implement plasticulture in their growing systems.

Effects of different mulches and net house on crucifer aphid (Brevicoryne brassicae L.) population, growth and yield of broadleaf mustard (Brassica juncea)

Crucifer aphid, Brevicoryne brassicae, is a key pest of broadleaf mustard and other crucifers. An alternative integrated management approaches are recommended to keep the pest below economic threshold level. A field experiment was carried out to evaluate the effect of mulching and net house on aphid population, growth and yield of broadleaf mustard. Experiment was carried out in randomized complete block design with four replications from September to December 2016 at Rampur, Chitwan, Nepal. Five treatments used in experiment was untreated control, black plastic mulch only, reflective plastic mulch only, black plastic mulch plus imidacloprid 70 WSG @ 0.13gm/liter, and net house plus black plastic mulch. The results showed that the lowest population of crucifer aphid was recorded inside the net house with black plastic mulch and black plastic mulch with imidaclorpid 70 WSG @ 0.13g/L spray. Reflective plastic mulch was superior as compared to black plastic mulch and control to reduce the aphid population. Similarly, the highest yield (26.86t/ha) was obtained inside the net house with black plastic mulch followed by black plastic mulch with imidacloprid spray (25.99 t/ha). But the benefit-cost ratio was the highest (4.09) in black plastic mulch with imidacloprid spray followed by reflective plastic mulch (3.42), black plastic mulch (3.32), and net house with black plastic mulch (3.10). Benefit-cost ratio was lower in net house with black plastic mulch but products are safe from toxins and potentially profitable in long run. Considering its ecological cost, the use of pest exclusion net is recommended as a viable option for controlling insect pests of broadleaf mustard.

Management of Pear Psylla (Hemiptera: Psyllidae) Using Reflective Plastic Mulch.

Pear psylla, Cacopsylla pyricola (Förster), has remained the most challenging pest of commercial pears in Washington and Oregon, the top producers of pears in the United States. The lack of effective integrated pest management tactics for this pest has been a major barrier to effective management. In this study, we examined the potential for reflective plastic mulch affixed beneath pear trees to suppress pear psylla. In 2017 and 2018, single pear tree (cv. Bartlett) plots of reflective plastic mulch, black plastic mulch, and no mulch (check) were established in a research orchard to compare their effects on pear psylla. Arthropods were sampled every 7-14 d from March through late summer. In both years, reflective mulch plots had significantly fewer pear psylla adults, eggs, and nymphs of the first generation compared with black plastic and check plots. However, later generations of psylla were not suppressed by reflective mulch. Semi-field tests were conducted in 2019 and 2020 using uniformly pruned potted pear trees on either reflective plastic mulch or grass to determine whether summerform adults were tolerant to reflected light from mulch, or if shading from vegetative growth negated the effect of the mulch. In both years, significantly fewer summerform adults and eggs were found in reflective mulch plots, suggesting that shading, rather than summerform tolerance, reduced effects from reflective mulch in the summer. This study demonstrates the potential for reflective mulch to suppress pear psylla and justifies future examination as part of a season-long management program.

THE INFLUENCE OF CULTURAL PRACTICE ON POPULATION OF PEA LEAFMINER (Liriomyza huidobrensis) AND ITS PARASITOIDS IN POTATO

Pea leafminer (Liriomyza huidobrensis) is the major pest of potato crop in Indonesia. The use of insecticides to control the pest is ineffective and harmful to the natural enemies. The study aimed to find out a promising cultural practice for leafminer management on potato crop. The study was conducted at a farmer’s field in Bali in 2004. Potato plants (Granola variety) were grown in a raised-bed plot of 10 m x 1 m. The treatments evaluated were standard cultural practice (C), C plus reflective plastic mulch (RPM) (CM), farmer’s practice (F), vermicompost (V), and V plus RPM (VM). All treatments were arranged in RCBD with five replications. From each plot, 10 plant samples were randomly taken to observe the presence of larvae, mines, and adults. Larvae and adults of leafminer and mines were separately counted from the top, middle, and bottom parts of the plant samples. Parasitoids were collected from the infested leaves of the plant samples. Emerged parasitoids were counted and put into vials with 70% ethyl alcohol and then identified. The results showed that the population of adults, larvae of L. huidobrensis, and mines were less in C, CM, V, and VM treatments compared to farmer's practice (F). However, RPM (CM and VM) treatments significantly reduced population of leafminer and mines. The highest population of adults, larvae, and mines on RPM treatment were less than 1.5, 8.5, and 10 per plant, respectively compared to other treatments which were greater than 3.2 for adults, 12.4 for larvae, and 12.7 for mines. Parasitoid population and parasitism level were more in vermicompost treatments (V and VM) compared to other treatments (C, CM, and F). The results showed that application of pesticides was ineffective against leafminer and reduced parasitoid population; in the other hand RPM was effective to control leafminer although the effect on parasitoids was not clear. Parasitoid species that were found associated with potato crop were Hemiptarsenus varicornis, Neochrysocharis sp., and Opius sp. Combination of RPM with standard practice and vermicompost are prospective for leafminer management in potato crop, however, VM is friendlier to environment regarding sustainable agriculture.

THE INFLUENCE OF CULTURAL PRACTICE ON POPULATION OF PEA LEAFMINER (Liriomyza huidobrensis) AND ITS PARASITOIDS IN POTATO

Pea leafminer (Liriomyza huidobrensis) is the major pest of potato crop in Indonesia. The use of insecticides to control the pest is ineffective and harmful to the natural enemies. The study aimed to find out a promising cultural practice for leafminer management on potato crop. The study was conducted at a farmer’s field in Bali in 2004. Potato plants (Granola variety) were grown in a raised-bed plot of 10 m x 1 m. The treatments evaluated were standard cultural practice (C), C plus reflective plastic mulch (RPM) (CM), farmer’s practice (F), vermicompost (V), and V plus RPM (VM). All treatments were arranged in RCBD with five replications. From each plot, 10 plant samples were randomly taken to observe the presence of larvae, mines, and adults. Larvae and adults of leafminer and mines were separately counted from the top, middle, and bottom parts of the plant samples. Parasitoids were collected from the infested leaves of the plant samples. Emerged parasitoids were counted and put into vials with 70% ethyl alcohol and then identified. The results showed that the population of adults, larvae of L. huidobrensis, and mines were less in C, CM, V, and VM treatments compared to farmer's practice (F). However, RPM (CM and VM) treatments significantly reduced population of leafminer and mines. The highest population of adults, larvae, and mines on RPM treatment were less than 1.5, 8.5, and 10 per plant, respectively compared to other treatments which were greater than 3.2 for adults, 12.4 for larvae, and 12.7 for mines. Parasitoid population and parasitism level were more in vermicompost treatments (V and VM) compared to other treatments (C, CM, and F). The results showed that application of pesticides was ineffective against leafminer and reduced parasitoid population; in the other hand RPM was effective to control leafminer although the effect on parasitoids was not clear. Parasitoid species that were found associated with potato crop were Hemiptarsenus varicornis, Neochrysocharis sp., and Opius sp. Combination of RPM with standard practice and vermicompost are prospective for leafminer management in potato crop, however, VM is friendlier to environment regarding sustainable agriculture.

Reflective Polyethylene Mulch Reduces Mexican Bean Beetle (Coleoptera: Coccinellidae) Densities and Damage in Snap Beans.

Mexican bean beetle, Epilachna varivestis Mulsant, is a serious pest of snap beans, Phaseolus vulgaris L., in the eastern United States. These beetles are intolerant to direct sunlight, explaining why individuals are typically found on the undersides of leaves and in the lower portion of the plant canopy. We hypothesized that snap beans grown on reflective, agricultural polyethylene (plastic mulch) would have fewer Mexican bean beetles and less injury than those grown on black plastic or bare soil. In 2014 and 2015, beans were seeded into beds of metallized, white, and black plastic, and bare soil, in field plots near Blacksburg, VA. Mexican bean beetle density, feeding injury, predatory arthropods, and snap bean yield were sampled. Reflected light intensity, temperature, and humidity were monitored using data loggers. Pyranometer readings showed that reflected light intensity was highest over metallized plastic and second highest over white plastic; black plastic and bare soil were similarly low. Temperature and humidity were unaffected by treatments. Significant reductions in Mexican bean beetle densities and feeding injury were observed in both metallized and white plastic plots compared to black plastic and bare soil, with metallized plastic having the fewest Mexican bean beetle life stages and injury. Predatory arthropod densities were not reduced by reflective plastic. Metallized plots produced the highest yields, followed by white. The results of this study suggest that growing snap beans on reflective plastic mulch can suppress the incidence and damage of Mexican bean beetle, and increase yield in snap beans.

Influence of Insecticides and Reflective Mulch on Watermelon Vine Decline Caused by Squash vein yellowing virus (SqVYV)

Watermelon vine decline (WVD) caused by the whitefly-transmitted Squash vein yellowing virus (SqVYV) has been a serious limiting factor in watermelon production in southwest and west-central Florida over the past few years. Symptoms of WVD typically appear as sudden decline of vines a few weeks before harvest or just after the first harvest. Fruit symptoms include rind necrosis and flesh discoloration that affects fruit quality and marketability. The combination of insecticide treatments consisting of an imidacloprid drench (Admire Pro, 560 ml/ha) at transplanting followed by two foliar applications of spiromesifen (Oberon, 2SC, 490 ml/ha) and reflective plastic mulch was evaluated for management of WVD during fall growing seasons of 2006, 2007, and 2009. Virus inoculum source was introduced by planting SqVYV-infected squash plants at the ends of each plot. In all three experiments, the insecticide-treated plots had significantly lower levels of WVD on foliage and fruit compared to non-treated plots. In 2007, the reflective plastic mulch was effective in reducing foliar WVD compared to non-reflective mulch, but not in 2006 and 2009. No significant interaction between plastic mulch and chemical treatments was observed on WVD development on foliage or fruit. Our results suggest that application of insecticides for managing whiteflies can help manage SqVYV-caused WVD. Accepted for publication 13 January 2015. Published 25 March 2015.

Economic Analysis of Three Soil-Surface Practices for Production of Fresh Market Tomato (Solanum lycopersicum L.)

Plastic and cover crop mulches are widely used in a number of vegetable crop production areas, but they currently are not commonly used in California. Evaluations of the effects of silver UV reflective plastic (RP) and cool-season cover crop (CC) mulches relative to the standard, bare-ground production system (ST) on growth, yield, and costs and returns of tomatoes were conducted in California. Biomass increased earlier over the RP mulch and was nearly twice that of both the ST and CC mulch at harvest. Yields were higher for RP (62,022 kg ha−1) and lower in the ST (37,467 kg ha−1) and CC mulch (25,005 kg ha−1) systems in 1999, and also highest in the RP in 2000. Costs in both the RP and CC mulch systems were higher than in ST system in both years and, based on returns on investment, were warranted in the RP system in both years, but only in 1999 in the CC system compared to the ST system. RP mulches may thus be a viable alternative for fresh market tomato production in California. CC mulches may be a useful alternative if productivity can be maintained using sustained no-tillage techniques.

An Investigation of Reflective Mulches for Use Over Capillary Mat Systems for Winter-time Greenhouse Strawberry Production

Photosynthethically active radiation (PAR) is a principle environmental variable used by horticultural specialists, agronomists, and ecosystem modelers to characterize the quantity and quality of light conducive to plant growth and development. Spatial distribution of PAR in a greenhouse can be quite variable and diffuse throughout the daytime photoperiod, especially at low sun angles in northern regions of the United States. Four colors of reflective plastic mulches (white, red, olive, and black) were evaluated for winter-time strawberry (Fragaria ananassa Duch.) production based on their reflectance and transmittance properties in a double-polyethylene, plastic-glazed Quonset greenhouse in Nebraska. The spectral properties of the plastic film mulches were investigated in the laboratory using a spectral radiometer and integrating sphere. For greenhouse spectral studies, a modified field of view set of LiCOR PAR sensors and infrared thermocouple sensors (IRT/c) were mounted over the greenhouse gravel floor and the strips of plastic films of four different colors. Both incident and reflected PAR and plastic mulch temperatures were recorded during the day using a wireless, LabVIEW-based data logger system. The red mulch reflected less than half the amount of PAR than that from the white mulch and the olive and black mulches reflected even less. The white 6-mil reflective mulch was then selected to cover a capillary mat (CapMatII) irrigation system in a greenhouse strawberry production study. A three-month production study using the white reflective mulch under 312 strawberry pots resulted in the production of over 1700 saleable berries with a mass of over 19 kg. Plastic mulches could enhance the PAR environment of greenhouses and thus translate to more consistent plant production during winter months.

Population dynamics of arthropods associated with early-season tomato plants as influenced by soil surface microenvironment

Two field studies were conducted in the San Joaquin Valley (SJV) of California in order to describe the association of arthropods and possible virus diseases with the plant canopy of early-season, bush-trained, fresh-market tomato ( Lycopersicon esculentum L. cv. Shady Lady) over three soil surface microenvironments. The experimental treatments were based on alterations to planting bed surfaces, as follow: 1) soil covered with silver metalized, light-reflective plastic mulch; 2) soil covered with biological mulch consisting of killed, chopped, cool-season cover crop residues [mixture of triticale ( X Triticosecale Wittm.), rye ( Secale cereale L. cv. Merced), and common vetch ( Vicia sativa L.)]; or 3) bare soil (not covered) – the SJV standard tomato production practice. In both studies, the predominant arthropods encountered in all treatments were the aphid species Aphis craccivora Koch, Macrosiphum euphorbiae Thomas, and Myzus persicae Sulzer; the western flower thrips ( Frankliniella occidentalis Pergande), and the false chinch bug ( Nysius raphanus Howard). These are all considered to be pests of cultivated tomato plants. Spiders were the most prevalent arthropod predator group recovered from foliage samples. All monitored arthropods, except spiders, were most abundant in tomato plants grown over the conventional, bare soil surface, and least abundant (P < 0.05) in plants grown over the silver plastic mulch. Spider numbers were highest in plant foliage over the biological mulch. Other arthropods commonly found on tomato plants in the SJV, including leafhoppers, whiteflies, various caterpillars, and predaceous taxa, were not commonly nor consistently encountered. This was likely due to the early-season timeframe of these studies. Similarly, foliar virus disease symptoms, which were originally targeted for monitoring, were virtually nonexistent. The only arthropod pest species encountered which consistently caused economically important damage to tomato fruit was N. raphanus. In both experiments, tomato fruits grown over the reflective plastic mulch had significantly less (69.5% and 39.7%, respectively) damage due to this pest than those over bare soil. The biological mulch gave inconsistent, intermediate damage reductions. Results from these two field studies showed that reflective plastic bed mulch suppressed populations of a variety of tomato canopy-associated arthropod taxa in early-season plantings, as compared to conventional, bare-soil beds. The biological bed mulch results were more inconsistent, but gave indications that killed cover crop residues, as well as the light-reflective plastic, may be of value in integrated pest management programs for fresh-market tomato production.

Reflective Plastic Mulch but not a Resistance-Inducing Treatment Reduced Watermelon Mosaic Virus Incidence and Yield Losses in Squash

Plant viruses, especially those transmitted by aphids in a nonpersistent manner, cause significant yield losses in cucurbit crops. Studies have shown that UV-reflective mulches can reduce insects from entering a crop with coincidental reductions in virus incidence. Treatment of plants with various forms of resistance-inducing agents have also shown promise for their ability to reduce plant virus incidence and associated losses. In this article, we describe a two-trial study that evaluated the integration of UV-reflective plastic mulch and a commercially available resistance-inducing treatment, BioYield™, to reduce the incidence and disease-related yield losses in summer squash [Cucurbita pepo var. melopepo (L.) Alef.] caused by the aphid-borne plant virus, Watermelon mosaic virus (WMV). In the spring trial, there was significantly reduced WMV incidence and whole treatment average enzyme-linked immunosorbent assay (ELISA) values among squash plants grown on silver-on-black (UV-reflective) mulch compared with plants grown on nonreflective black mulch. Significantly greater squash fruit yields were obtained for plants grown on the silver-on-black mulch relative to the black mulch treatment. In the fall trial, highly UV-reflective silver mulch was used in addition to silver-on-black and black mulches. WMV incidence and whole treatment average ELISA values were significantly lower for squash plants in the silver mulch treatment compared with silver-on-black and black mulch treatments. The silver-on-black treatment resulted in lower WMV incidence and whole treatment average ELISA values compared with the black mulch treatment. Squash plant yields were significantly greater for plants in the silver-on-black mulch treatment than for those in the silver or black mulch treatments. Treatment of squash plants with BioYield™ did not reduce virus incidence, or whole treatment average ELISA values, nor did it result in higher squash fruit yields compared with the nontreated control in spring or fall trials.

Reflective plastic mulch as control measure for onion thrips, Thrips tabaci (Lindeman), in persimmon orchards

Reflective plastic mulch as control measure for onion thrips, Thrips tabaci (Lindeman), in persimmon orchards

(29) Effects of Colored Plastic Mulches on Bell Pepper Yield and Fruit Characteristics

A study was carried out to compare the effects of different colored plastic mulches (black smooth, red, black embossed, blue, olive, yellow, clear, white, and reflective) and bare ground on bell peppers (Capsicum annum) yield and fruit characteristics. Pepper varieties `Crusader' (2004 trial) and `Boynton Bell F1' (2005 trial) seeds were planted in flats filled with Jiffy Mix in a greenhouse in late Apr. 2004 and 2005, and the seedlings transplanted in early June 2004 and 2005, respectively. In 2004, pepper fruits were harvested once in early September, and reflective and black embossed plastic mulch treatments had higher U.S. No. 1 fruit weight than other treatments. Pepper fruits harvested from reflective plastic mulch treatment were longer and larger than fruits in other treatments. In 2005, pepper fruits were harvested three times in late September to early October, and plants grown in reflective and red plastic mulch treatments had higher Fancy fruit weights while olive and white plastic mulch treatments had higher U.S. No. 1 fruit weights than other treatments. Fruits from reflective and red plastic mulch treatments were longer and larger than fruits from other treatments. The total marketable yield (Fancy and U.S. No. 1 fruit weight combined) was higher in olive, reflective, white, and red plastic mulch treatments. In comparison with black embossed plastic mulch, plants grown in reflective and olive plastic mulches had higher yield in 2004. However, in 2005, yield followed the same trend, with plants grown in olive, white, and reflective plastic mulches having higher yield than other treatments.

(183) Effects of Colored Plastic Mulches on Tomato Growth and Yield

Different colored plastic mulches can influence tomato (Lycopersicon esculentum L.) growth and yield. A study was carried out to compare the effects of different colored plastic mulches and bare ground on growth and yield of tomato. Ten treatments, namely, control (bare ground), and plastic mulches (black smooth, red, black embossed, blue, olive, yellow, clear, white, and reflective) were replicated four times in a randomized complete-block design. Tomato variety `Sunstart' seeds were planted in flats filled with Jiffy Mix in a greenhouse in late Apr. 2004 and seedlings transplanted in early June 2004. The seedlings planted in white and reflective plastic mulches were taller than seedlings planted in black smooth, black embossed, clear, blue, red, and olive mulches by 24 July 2004. Weeds were growing underneath clear, yellow, and red plastic mulches, and squash bugs were observed in yellow plastic mulch treatment on 2 July. Cumulative marketable tomato yield was highest in plants grown in reflective and white plastic mulches, and lowest in plants grown in yellow plastic mulch. Marketable fruits from plants grown in reflective and white mulches were larger than fruits from other treatments. In comparison with black embossed plastic mulch, plants grown in reflective and white plastic mulches had 2 and 1.2 tons/acre higher marketable yields, respectively, than plants grown in black embossed plastic mulch.

(184) Effects of Colored Plastic Mulches on Muskmelon Growth and Yield

Colored plastic mulches can influence muskmelon (Cucumis melo L.) growth and yield. A study was carried out at the St. Charles Horticulture Research Center, St. Charles, Ill., to compare the effects of different colored plastic mulches on vine length and yield of muskmelons. An experiment was carried out with 10 treatments, namely, control (bare ground), and plastic mulches (black smooth, red, black embossed, blue, olive, yellow, clear, white, and reflective) in a complete randomized block and replicated four times. Muskmelon variety `Athena' seeds were started in the greenhouse in late Apr. 2004 in flats filled with Jiffy Mix, and transplanted in mid-May 2004. Seedlings planted in black embossed, olive, red, blue, and white plastic mulches had longer vines than seedlings transplanted in black smooth, reflective, clear, and yellow mulches by 24 July. Seedlings planted on the control (bare ground) had much shorter vines compared to seedlings in other treatments. The cumulative fruit number and weight was higher in blue, olive, red, and black embossed plastic mulches than in plants grown in clear, yellow, and reflective plastic mulch treatments. Plants grown in white and reflective mulch treatments had larger fruits than plants in other treatments. In comparison with black embossed plastic mulch, plants grown in blue, olive, and red plastic mulches had higher fruit number and yields.

Mulches reduce aphid-borne viruses and whiteflies in cantaloupe

We compared reflective plastic and wheat straw mulches with conventional bare soil for managing aphid-borne virus diseases and silverleaf whitefly in cantaloupe. The occurrence of aphid-borne virus diseases was significantly reduced with both mulches as opposed to bare soil, and reflective plastic performed better than wheat straw. Silverleaf whitefly numbers, both adults and nymphs, were reduced equally by plastic mulch and wheat straw, and were significantly lower than with bare soil. Reflective plastic produced mature melons sooner and more cartons per acre than the other production systems. The reflective plastic system also produced a greater number of large-size melons, which are favored in the late-season market. Plants grown over straw mulch produced higher overall yields, including large-size melons, than those grown over bare soil.