White Plastic Mulch Research Articles

Effect of plastic film mulch and irrigation water regimes on soil temperature pattern, plant growth and water productivity of maize

In arid and semi-arid climate, combining different plastic film mulches and irrigation water regimes may be lead to enhance of grain yield and water use efficiency (WUE) with water saving. For the optimum grain yield of maize crop, soil water content and temperature, and irrigation water use efficiency are still not well understood in the climate of Sindh, Pakistan. Therefore, the aim of this study was to examine the soil moisture pattern, soil temperature, yield and WUE under interaction of mulching and soil water status. This field experiment was conducted at the station of department of Irrigation and Drainage during cropping seasons 2021–22. In field trial involved three mulching modes (black and white film, without film) and two irrigation water regimes (sufficiently and severely water stress). The results showed that across the irrigation water regimes treatments, without mulched treatment plants depressed both moisture status and temperature of the soil, nonetheless, the decrease soil water status was more pronounced compared with the reduction in soil temperature. Plant dry biomass was improved when mulching with black plastic film as exemplified by the increased plant height, indicating the increased plant biomass. However, across the mulching treatments, by improving the plant micro-climate condition by black colored plastic film mulching increased significantly grain yield by 17–47% and WUE by 16–46% because less soil water depletion as compared with white plastic mulch and without mulch treatments, respectively, causing the serious waste of water resources. Across the water regimes, sufficiently water stressed condition (80% of soil water holding capacity, SWHC) could significantly enhance grain yield by 17.4% and WUE by 8% as compared to moderately water stressed condition (50% of SWHC). Mulching with black colored plastic film is suggested for maize in terms of high grain yield and water use efficiency with a minor dry biomass reduction.

Evaluating the Effects of Deficit Irrigation and Mulch Type on Yield and Yield Components of Onion in Fogera, Ethiopia

Water scarcity is a challenge for current irrigated agriculture globally. Under these circumstances, new on-farm irrigation management strategies should be established. An experiment was conducted at Fogera in 2021 to evaluate the effects of deficit irrigation (DI) and mulch type on onion yield and yield components. A factorial combination of three levels of DI (100%ETc, 75%ETc, and 50%ETc) and three mulch types No Mulch (NM), White Plastic Mulch (WPM), and Rice Straw Mulch (RSM)) were evaluated in RCBD with three replications. Monthly ETo, ETc, and irrigation scheduling were computed using CROPWAT 8.0 model. These studies showed that the onion yield and yield components were significantly affected by the main and the interaction effects. The maximum average plant heights (PH), leaf heights (LH), and number of leaves per plant (LNP) of 51.7 cm, 38.0cm, and 10.4 respectively, were recorded from 100%ETc whereas the minimum PH, LH, and LNP of 39.5 cm, 29.0cm, and 6.9 were recorded from 50%ETc treatment respectively. The highest average bulb weight (BW), bulb diameter (BD), and bulb height (BH) were 117.9gr, 6.4, and 5.7 cm recorded from 100%ETc treatment respectively. In contrast, the minimum average BW, BD, and BH were 79.9gr, 4.8, and 5.0cm recorded from 50%ETc respectively. The highest PH, LH, and LNP of onions were 51.9cm, 40.6cm, and 10.1 respectively recorded from RSM treatments. In contrast, the minimum PH, LH, and LNP of onions were 41.5cm, 31.1cm, and 7.5 respectively, recorded from WPM treatments. Similarly, the highest mean BW, BH, and BD 106.2gr, 5.8cm, and 6.0cm were obtained from the treatments of RSM respectively. In contrast, the lowest mean BW, BH, and BD 100.7gr, 5.0cm, and 5.3cm were obtained from NM treatments respectively. The interaction effects of DI and mulch showed that the onion yield at 100%ETc with RSM was 7.5% higher than that at 100%ETc with NM and 15.1% higher than the yield at 100%ETc with PM. The highest BW, BH, and BD of the onion 121.8 gr, 6.2, and 6.8 were obtained when the onions received 100%ETc and mulched with RS while the lowest average BW, BH, and BD of the onion were 77.3gr, 4.6cm and 4.1cm were obtained from 50%ETc with NM treatment combination. These results showed that RSM with 75%ETc improves onion yield and yield components.

Effect of Deficit Irrigation and Mulch on Field and Water Productivity of Tomato Under Drip Irrigation at Ambo Agricultural Research Center, West Shewa, Ethiopia

Ethiopia produces far fewer tomatoes than the world average due to poor management techniques. It was found that the soil moisture and agroclimatic conditions affected how tomatoes reacted to water management during irrigation. In order to assess the impacts of irrigation level and mulch types on the yield, yield components, water productivity, and economic return of drip irrigated tomato production, a field experiment was carried out at the Ambo Agricultural Research Center Farm Site in 2021–2023. The experiment was a two-factor factorial experiment arranged in a randomized complete block design. The two factors were the four irrigation levels (55%ETc, 85%Etc, 70%ETc and 100%ETc) and three mulch types (no mulch, wheat straw mulch, and white plastic mulch). The two-year data on fruit yield, yield components, and water productivity were subjected to analysis of variance using SAS 9.4 software with a significance level (p≤ 0.05). least significant difference test was applied for statistically significant parameters to compare means among the treatments. The best soil moisture depletion levels, as determined by statistical analysis, are 100% ETc, 85% ETc, and 70% ETc, with marketable fruit yields of 56,405 kg/ha, 45,331 kg/ha, and 41,769 kg/ha, respectively. As for mulch types, the best practices are wheat straw mulch and white plastic mulch, with marketable fruit yields of 45,721 kg/ha and 44,514 kg/ha, respectively, for the study area. However, the results of the partial budget analysis results showed that, with net incomes for onion production in the research region of 1,350,930 ETB/ha and 1,367,071 ETB/ha, respectively, 85% ETc and wheat straw mulch are the economically optimal methods.

Comparison of different mulching options for improving water productivity and maize yield in a semi-arid climate, Northern Ethiopia, Tigray

This study compared the effectiveness of organic and inorganic mulching options for improving soil moisture content (SMC), water productivity (WP), and maize yield. The objectives of the study were to (a) investigate the effects of organic and inorganic mulches on SMC and water productivity, (b) quantify maize yield improvements due to the application of organic and inorganic mulches. The experiment was set up with a randomized complete block design with four treatments, namely black plastic mulch (BPM), white plastic mulch (WPM), flax straw mulch (FSM), and a control. The result indicated that WPM, BPM, and FSM increased maize yield by 66.1, 47.0, and 1.9% compared to the control. The net returns with the application of WPM, BPM and FSM were 1459.0, 1119.6, and 847.1 USD/hectare, respectively. Similarly, WPM, BPM, and FSM increased WP by 184.5, 127.6, and 39.4%, respectively. SMC was also increased by 16, 10.8, and 3.5% by WPM, BPM, and FSM, respectively. Inorganic mulches had a significant effect on WP and maize yield. On the other hand, FSM did not have any significant effect on WP and maize yield. The findings of this study indicated that inorganic mulches are useful for improving WP and maize yield. It is therefore necessary to apply inorganic mulches to improve WP and maximize maize yield in areas with a semi-arid climate such as northern Ethiopia.

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.

Plastic mulches improve yield and reduce spotted-wing drosophila in primocane raspberry

Plastic mulches are increasingly used by growers producing perennial fruit crops to improve vegetative and fruit biomass, promote earlier yield, increase fruit quality, and enhance weed suppression. In this two-year study, we evaluated how black, white, and metallic plastic mulches impact primocane raspberry vegetative biomass, fruit yield and quality, and spotted-wing drosophila (Drosophila suzukii; SWD) infestation in a humid continental climate. All three plastic mulches increased vegetative biomass compared to the control with grass within the row. Marketable fruit yield was increased by 68-139%, 44-76%, and 33-110% in the black, white, and metallic plastic mulch plots, respectively, compared to the control. The black mulch extended fruit production by two weeks compared to the other treatments. Increases in vegetative and fruit biomass may be attributable to increased soil temperature under the black plastic mulch and increased reflection of photosynthetic active radiation (PAR) in the white and metallic mulches. None of the plastic mulches impacted the fruit quality parameters assessed, including soluble solids content, pH, titratable acidity, anthocyanin concentration, and total phenolics, compared to the control. All three plastic mulches reduced the proportion of unmarketable fruit, likely due to their 40-71% reduction in SWD larval infestation of fruit compared to the control. Overall, black, white, and metallic plastic mulches are an effective cultural practice for managing SWD while simultaneously increasing fruit and vegetative biomass.

Pengaruh Metode Pemupukan dan Berbagai Jenis Mulsa Terhadap Pertumbuhan dan Hasil Tanaman Stevia (Stevia Rebaudiana Bertoni) dengan Irigasi Tetes

This study wants to find the best fertilizing method and kind of mulch for better growth and yield of stevia. The research was conducted at October-February in PT. Daya Santosa Rekayasa, Karangploso, Malang at an altitude ±750 MAMSL. The research uses Split Plot Design using RBSL model with two factors and four replications. The first factor which is also used for the main plot is fertilizing method using fertigation (A1) and conventional method (A2). Second factor also uses as the subplot are black white plastic mulch (U1), rice straw mulch (U2), and without mulch (U3). Nondestructive variable was height of the plant and number of leaves. Destructive variable was observed in harvest time such as fresh weight of plant, fresh weight of yield, dry yield, root length, chlorophyll amount, and sucrose rate. The data will be tested using ANOVA and T-Test, if there is a significant difference, then will be processed again using Duncan Multiple Range Test (DMRT). The result showed that there is no significant interaction between the fertilizing methods and types of mulches in stevia. Fertigation and conventional method give no significant difference in growth or yield stevia but fertigation gives better result in every variable. Types of mulches show that black white plastic mulches give the best impact to height of the plant, number of leaves, fresh weight of plant, fresh weight of yield, dry yield, root length, and chlorophyll amount with fresh yield 11,4 gr each plant and also dry yield 2,27 gr.

Uso de Acolchados Plásticos para Reducir Diaphorinia citri 1-Huanglongbing e Incrementar el Rendimiento de Lima Mexicana en el Trópico Seco de México

Huanglongbing (HLB) vectored by Asian citrus psyllid (Diaphorina citri) severely affects commercial plantations of Mexican lime (Citrus aurantifolia) in the dry tropic region of Mexico. Management of Huanglongbing is based on intensive use of agronomic practices such as irrigation, nutrition, pruning, and weed, insect pest, and disease control. During 2018 to 2022, the effect of black, white, aluminum, and green plastic mulches, a white polypropylene mesh (ground cover), and bare soil (traditional system), were evaluated on D. citri and incidence-severity (I-S) of Huanglongbing, and Mexican lime yields. Trees with all types of plastic mulch had less I-S during the first 13 months of the study (35 to 40% of affected foliage) compared to bare soil (74% of tree affected). Also, plots with plastic mulches had fewer Asian citrus psyllid adults (one to 16 insects/trap/week) as compared with bare soil (11 to 28 adults). Mulched treatments had a positive effect on fruit production. After 4 years, plots with white, aluminum, green, and black plastic yielded 41.6, 40.1, 39.6, and 34.9 t/ha. Bare soil yielded only 26.6 t/ha. The cost to install plastic mulches was $526/ha. Because of that, the plastics increased yields by 50-56% and the average price of Mexican lime fruit was about $600 per ton. This production system is an economically profitable alternative to the growers to coexist with Huanglongbing in the dry tropics of Mexico.

Efeect of Environmental Parameters on Chrysanthemum Different Colour Low Tunnel Shade Nets and Different Colour Mulches

Shade nets are used for controlling the crop growth and improving crop productivity. A field experiment was conducted under shade net to determine the effect of environmental parameters on chrysanthemum under on different colour low tunnel shade nets. The experiment had split plot design consisting of different colour shade nets as main plots i.e., white shade net, green shade net, black shade net and open field condition and different mulches as a sub plots i.e., white colour plastic mulch, silver colour plastic mulch, black colour plastic mulch, jute mulch and no mulch. White colour shade net significantly increased the soil moisture and lowered the soil temperature compared to other colour shade nets. During the experimental period, maximum temperature (37.90 °C) was recorded under control condition followed by black shade net (35.80 °C) and green shade net (34.60 °C). Minimum temperature (33.00 °C) was recorded under white shade net. Maximum relative humidity (86.20 %) was recorded under white shade net followed by green shade net (82.30 %) and black shade net (79 %). Minimum relative humidity (77 %) was recorded under control condition. Maximum light intensity (49600 Lux) was recorded under control condition followed by white shade net (46800 Lux) and green shade net (37,000 Lux). Minimum light intensity was recorded under black shade net (33210 Lux). The results of biometric parameters depicted higher growth and yield parameters for chrysanthemum grown under white shade net with white plastic mulch. The yield of Chrysanthemum was increased in white shade net (8.75 t ha-1) than the black shade net (4.43 t ha-1). Chrysanthemum grown in open fields and without mulch produced lower growth and yield.

Response of different colored plastic mulches on growth and yield of okra (Abelmoschus esculentus L.)

Field experiments were conducted during kharif seasons of 2016-17, 2017-18 and 2018 -2019 at Zonal Research Station, Darisai, East Singhbhum, Jharkhand to study the effect of coloured plastic mulches on growth and yield of okra crop. The experiments were laid out in randomized block design with seven treatments viz; T1 - White plastic mulch, T2 - Black plastic mulch, T3 - Yellow plastic mulch, T4 - Silver black plastic mulch, T5 - blue plastic mulch, T6 - Straw mulch, T7 - Bare soil (without mulch) and were replicated thrice. The results indicated that plant height and number of branches were better for the plants grown over plastic mulches compared to bare soil. The significantly highest yield (180.86 q/ha) was obtained in silver black plastic mulch compared to bare soil (92.52 q/ha). Mulching increased fruit yield relative to bare soil as the plants grown on silver/black plastic mulch indicated a 95% increase in yield compared to control treatment. The silver/black plastic mulch resulted 92.54% reduction in weed. Okra crop with silver/black plastic mulch recorded the highest net income (246496.11Rs/ha) and benefit cost ratio (2.97).

The effect of different types of mulch and different cultivation methods on the quantitative and qualitative traits of sunflower (Helianthus annuus L.) in Ahvaz climate

To investigate the effect of mulch and different cultivation methods on the quantitative and qualitative yield of oil sunflower (Helianthus annuus L.) in Ahvaz climate, a factorial experiment in randomized complete blocks with three replications in the 2017-2018 crop year was in the research farm of Agricultural Sciences and Natural Resources University of Khuzestan. The first factor includes different types of mulch in five levels (non-application, wheat straw, white plastic, live mulch (mung bean cultivation), and black plastic) and the second factor includes three-level cultivation method (on a flat surface, ridge cultivation, and inside the furrow cultivation). The results showed that in the flat surface and on the ridge, black plastic produced the highest amount of chlorophyll a, b, and In the inside the furrow, the highest chlorophyll a was obtained in the application of living mulch. The highest grain yield and oil yield were obtained from the interaction of wheat straw mulch × in the furrow and wheat straw mulch on the ridge. In addition, the highest harvest index was obtained in the treatment of white plastic mulch on a flat surface with an average of 51.85%. In general, it can be said that the treatment of wheat straw and straw × in the inside the furrow and wheat straw × on the ridge were superior in terms of quantitative and qualitative performance.

Effects of Mulching and Amount of Water on Yield and Yield Components of Tomato under Drip Irrigation at Adola Rede District, Southern Ethiopia

Water has been recognized as one of the scarcest inputs, which can severely avoid agricultural production and productivity unless it is carefully conserved and managed. This study has investigated the effects of mulching and amount of water on yield and yield components of tomato ( Solanum Lycopersicum L.) under drip irrigation at Adola rede District, Southern Ethiopia. The treatments of the study involved combination of three drip irrigation levels (100, 75, and 50% of crop water requirement, ETc) and three mulches (No mulch, white polyethylene sheet, and wheat straw). The yield and yield components in the mulched treatment with excessive stages of irrigation have been considerably higher in compared to these in the unmulched treatments. The yield of tomatoes increased with the growing quantity of irrigation water in mulched treatments. The highest marketable fruit yield for each mulch (35478kg ha -1 for white mulch and 28831kg ha -1 for straw mulch) was obtained when 75% of the crop water requirement used to be applied. With 100% water application, the white plastic mulched treatment produced a decrease marketable fruit yield than the straw-mulched treatment. The best water productivity of (12.915kg m -3 ) was received with 75% water application under white plastic mulch, But statistically non-significant with straw mulch under 75% crop water requirement application. The highest net benefit of 563475.7ETB ha -1 was recorded from white plastic mulch with 75% ETc and followed by 484454.7ETB ha -1 with Straw mulch with 75% ETc. The lowest net advantage 285477.3ETB ha -1 was acquired from no mulch with 50% ETc. The lowest net benefit to cost ratio was gained under treatment straw mulch with 75% ETc (15.04) and followed by no mulch with 100% ETc (14.32). This end result showed that wheat straw mulch with 75% ETc is economically feasible for tomato production in the Adola area of the Guji zone. Keywords: Crop Water Requirement, Tomato, Drip, Mulching, Water Levels, Marketable Fruit Yield DOI: 10.7176/JEES/12-11-01 Publication date: November 30 th 2022

Impact of Different Colour Low Tunnel Shade Nets and Mulches on Water use Efficiency and Nutrient use Efficiency in Chrysanthemum

An investigation was carried out in an experimental field of the College of Agricultural Engineering, University of Agricultural Sciences, Raichur, to investigate the effect of different coloured low tunnel shade nets and different mulches on water use efficiency and nutrient use efficiency of chrysanthemum. The results revealed that the values of daily evapotranspiration under different colours’ low tunnel shade net were less than the values of evapotranspiration under open field for all months. It is because of the green-house effect and low radiation. The values of ET during the seasons were lower under white-coloured shade net compared to open field conditions. The results indicate that significant irrigation water savings occur in chrysanthemums under different coloured low tunnel shade nets as compared to open field cultivation. It is also found that the chrysanthemum crop requires approximately 31%, 28%, and 23% less water under white, green, and black shade net compared to the total water required under open field cultivation. The highest water use efficiency was recorded with the white colour low tunnel shade net (28.78 kg ha-1 mm-1) and this was followed by the green shade net (28.64 kg ha-1 mm-1), black shade net (13.09 kg ha-1 mm-1) and lowest water use efficiency was recorded under open field conditions (10.58 kg ha-1 mm-1). Among the different mulches, the highest water use efficiency was recorded by the use of white coloured mulch (24.36 kg ha-1 mm-1) and this was followed by silver mulch (21.75 kg ha-1 mm-1), black mulch (20.82 kg ha-1 mm-1), and jute mulch (19.38 kg ha-1 mm-1). The lowest water use efficiency was recorded where mulch was not used (15.05 kg ha-1 mm-1). The highest nutrient use efficiency was recorded with the white colour low tunnel shade net (Nitrogen (N)=72.51 kg ha-1, Phosphorous (P)=12.37 kg ha-1 and Potassium (K)=73.84 kg ha-1 ) and this was followed by the green shade net (N=66.77 kg ha-1, P=10.28 kg ha-1 and K=64.33 kg ha-1), open field conditions (N=58.08 kg ha-1, P=8.72 kg ha-1 and K=56.36 kg ha-1) and lowest nutrient use efficiency was recorded under black shade net (N=51.60 kg ha-1, P=6.98 kg ha-1 and K=49.75 kg ha-1). Among the different mulches, the highest nutrient use efficiency was recorded by the use of white colour mulch (N=77.53 kg ha-1 P=11.74 kg ha-1 and K=73.20 kg ha-1) and this was followed by silver mulch (N=70.50 kg ha-1, P=10.61 kg ha-1 and K=66.86 kg ha-1), black mulch (N=65.08 kg ha-1, P=9.51 kg ha-1 and K=64.09 kg ha-1), and jute mulch (N=57.75 kg ha-1, P=8.96 kg ha-1and K=64.09 kg ha-1). The lowest nutrient use efficiency was recorded where mulch was not used (N=40.22 kg ha-1, P=7.11 kg ha-1 and K=44.44 kg ha-1). The results indicated that there is a bright scope for cultivation of chrysanthemum under white colour low tunnel shade net with white plastic mulch.

Substitution Experiment of Biodegradable Paper Mulching Film and White Plastic Mulching Film in Hexi Oasis Irrigation Area

Biodegradable paper mulch has the advantages of being easily degradable and environmentally benign, but its own performance and adaptability to harsh environments have not been tested. This paper uses scanning electron microscopy and three-dimensional morphometry to microscopically characterize biodegradable paper mulch and white plastic mulch. To analyze and compare their mechanical and hydrophobic properties, and weather resistance, the two mulches were measured through tensile tear load and static contact angle. A comparative analysis of the effect of mulching in the dry crop area of the Hexi Corridor was conducted by comparing the growth index, farm water heat, soil oxygen content, and yield using maize and flax. The test results show that biodegradable paper mulch films were slightly inferior to traditional white mulch films in terms of mechanical and hydrophobic properties, with inadequate insulation and moisture retention, but better in terms of aging resistance, soil oxygen content, and crop insulation and water storage capacity in the middle and growth stages. White mulch film had a better yield enhancement effect on maize, while with biodegradable paper mulch film, this was more significant with flax.

MODELING THE ONION YIELD RESPONSE TO DEFICIT IRRIGATION AND MULCH USING MULTIPLE REGRESSION MODEL IN SEMI-ARID NIGERIA

Effect of deficit irrigation, mulch practices, crop growth and water use parameters on the yield of Onion was modeled using a multiple linear regression model. The crop evapotranspiration, number of leaves, leaf height and canopy cover of the Onion were used as the independent variables. Onion bulb yield was the dependent variable under four mulching materials (rice straw, RM; wood shaving, WM; white synthetic plastic, SM and no mulch, NM) in the semi-arid region, of Nigeria. The regression analysis revealed that the independent variables in the model predicted the Onion bulb yield significantly (p < 0.05) under mulching conditions, while no mulch plots yielded no significance as indicated by the ANOVA statistic. The overall model degree of determination (r2) of the dependent variable of 0.97, 0.97, 0.98, and 0.81 were obtained under SM, WM, RM, and NM respectively indicating that the multiple regression model predicted the dependent variable satisfactorily. The co-efficient values show that the highest coefficient was obtained at the number of leaves (0.56) followed by crop evapotranspiration (0.33). It was observed that among the four multiple regression models developed, the model obtained with white synthetic plastic mulch produce a better yield. Thus, white synthetic plastic mulch conserved soil moisture thereby improving Onion bulb yield. When the models were tested, a slight overestimation of the Onion bulb yield at both mulched and no mulched regression models was observed as compared with the yield from the field. Therefore, the model obtained with white synthetic plastic mulch produces a better yield.

Combining Cultural Tactics and Insecticides for the Management of the Sweetpotato Whitefly, Bemisia tabaci MEAM1, and Viruses in Yellow Squash

The sweetpotato whitefly, Bemisia tabaci MEAM1 Gennadius (Hemiptera: Aleyrodidae), and the complex of viruses it transmits are major limiting factors to squash production in the southeastern United States. At this time, insecticides are extensively relied upon for the management of whiteflies and, indirectly, whitefly-transmitted viruses. The development of a multi-faceted, integrated pest management (IPM) program is needed to increase the sustainability and profitability of squash production. Experiments in 2018 and 2019 evaluated the effects of insect exclusion netting (IEN) in combination with selected pesticides on whitefly population dynamics and virus incidence in greenhouse-grown squash seedlings. Field experiments from 2018 to 2021 evaluated the effects of mulch type (UV-reflective mulch, live mulch, and white plastic mulch), row covers, and insecticides on whitefly population dynamics, silver leaf disorder (SSL) intensity, virus symptom severity, and marketable yield. IEN significantly reduced whiteflies and virus incidence on squash seedlings in the greenhouse study. In the field mulch study, lower whitefly abundance and SSL intensity, as well as reduced virus symptom severity, were observed in plots with reflective mulch compared with white plastic or live mulch. In the insecticide/row cover study, whitefly abundance, SSL intensity, and virus symptom severity were lowest in the row cover and cyantraniliprole- and flupyradifurone-treated plots. Field plots with row covers and those with UV-reflective mulch consistently produced the greatest marketable yields. These findings demonstrate that growers can reduce whitefly and virus pressure and preserve yields in squash production in the southeastern United States by combining cultural and chemical tactics, including row covers, UV-reflective mulch, and select 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 Deficit Irrigation and Mulching on Yield and Water Productivity of Furrow Irrigated Onion (Allium Cepa L.) Under Haramaya Condition, Eastern Ethiopia

In the background of improving Water Productivity, there is concern in deficit irrigation, which delivers a means of decreasing water depletion while reducing opposing effects on yield. A field experiment was conducted at Haramaya, Ethiopia during 2020 off-season. The objective was determining effects of irrigation levels and mulch types on yield and Water Productivity of Onion. The experimental design was a split plot in RCBD with three replications. The deficit irrigation levels 100%, 85%, 70% and 55% ETc used with the three mulch types no mulch, straw and white plastic mulch were used. The results revealed that the maximum yield of 38.43 ton ha-1 was recorded from 100% ETc with plastic mulch; whereas the minimum yield of 16.36 ton ha-1 was recorded from 55% ETc with no mulch. Higher Crop Water Productivity of about 9.04 kg ha-1mm-1 was obtained from 85% ETc with plastic mulch. With 85% ETc and plastic mulch the water saved, yield reduction and Crop Water Productivity were 113.13 mm, 9.57% and 9.04 kg ha-1 mm-1 respectively. In view of water saved and maximum yield, irrigation water application at 85% irrigation application levels and plastic mulch could be concerned. The current study recommends that, in water limited area, farming community can accept deficit irrigation level with 85% ETc under plastic mulch.

Effects of soil preparation and mulching practices together with different urea applications on the water and nitrogen use of winter wheat in semi-humid and drought-prone areas

Soil preparation and mulching practices in combination with slow-release urea application are important measures for agricultural yield enhancement. However, slow-release urea may cause a yield reduction due to insufficient fertility in early crop growth. We considered whether the ridge-furrow plastic-mulching (RFP) system using different mulch colors could offset this disadvantage. An experiment was conducted using a randomized split-plot design with three soil preparation and mulching practices as the main-plot treatments in combination with three different urea applications as sub-plot treatments. The three soil preparation and mulching practices were flat cropping without mulch (F), the RFP system with white plastic mulch over the ridge (W), and the RFP system with black plastic mulch over the ridge (B); the three urea applications were no urea (N0), slow-release urea (NS), and ordinary urea (NU). The results showed that compared to F, the RFP system (especially B) could increase the use of precipitation and reduce soil water depletion, which ultimately increased the water productivity (WP) of winter wheat. In addition, the nitrogen use efficiency of NS was further improved under the RFP system, while there was essentially no difference between the two different urea types under F. In summary, B could take full advantage of NS to coordinate the relationship between effective spikes per unit area, grains per spike, and 1000-grain weight, maximizing the WP, nitrogen use efficiency, and grain yield. Between 2016 and 2019, the WP and grain yield of B-NS increased by 79.2–107.0% and 75.7–87.0%, respectively, compared to the lowest value (F-N0). The nitrogen agronomic efficiency (NAE), nitrogen physiological efficiency (NPE), nitrogen recovery efficiency (NRE), and nitrogen partial factor productivity (NPFP) of B-NS increased by 116.1–123.3%, 28.5–34.8%, 66.1–71.9%, and 44.1–53.2%, respectively, compared with the lowest value (F-NU).