Pumpkin Yield Research Articles

Impact of the low and high concentrations of fly ash amended soil on growth, physiological response, and yield of pumpkin (Cucurbita moschata Duch. Ex Poiret L.).

Fly ash, a result of coal burning in thermal power plants, is sustainably used in agriculture and has been regarded as a problematic solid waste worldwide. The presence of some desired nutrients (macro and micro) and its porosity makes it a marvelous soil amendment for plant growth and development. The present study was done to evaluate the effect of different fly ash levels on pumpkin crop (Cucurbita moschata). Pot experiment in randomized block design was conducted with different fly ash supplement treatments to analyze the impact of fly ash on growth, chlorophyll, carotenoid, biochemical parameters, and pumpkin crop yield. The results show variation in soil's physical and chemical properties after the application of fly ash (30 and 50%). Also, the lower levels (10-30%) of fly ash amended soil significantly (P ≤ 0.05) enhanced the growth (plant height, plant fresh and dry biomass, no. of leaves, and average area of the leaf), chlorophyll content, and biochemical contents (protein, carbohydrate, mineral, and leaf water content) in pumpkin crop. The proline content was also observed to enhance by the increasing levels of fly ash to soil. The yield parameters in terms of a number of flowers and fruits, fruits' length and diameter, and fresh and dry weight of fruits were also significantly increased in amended soil with 10-30% fly ash. On the other hand, the higher doses, i.e., 40% and 50% of fly ash showed a negative effect and reduced the growth, chlorophyll, carotenoid, biochemical content, proline, and yield in pumpkin crop. We concluded that the lower level of fly ash (up to 30%) could be used as fertilizer in agricultural fields for the improvement of vegetable as well as other food crops in a sustainable manner but the higher level of fly ash (40 and 50%) is toxic to the plant.

Yield and Quality of Lettuce, Pumpkin, and Watermelon Varieties Grown Under Five Soil Management Practices

A field experiment was conducted to investigate the impact of five soil treatments: municipal sewage sludge (SS), horse manure (HM), chicken manure (CM), vermicompost (Vermi), and no-mulch (NM) native soil on the yield and quality of three lettuce, Lactuca sativa varieties (Romaine, Bibb, and Butterhead), three watermelons varieties (Sugar Baby, Crimson, and Charleston Grey), and three pumpkin varieties (Renegade, Howden, and Gumdrop). The objectives were to assess plant yield and quality responses to different amendments and soil urease, invertase, acid and alkaline phosphatase activity. At maturity, heads and fruits were harvested, weighed, and graded according to the USDA grades into Fancy, U.S. No. 1 and U.S. No. 2. Overall lettuce yield obtained from SS and CM amended soils was significantly greater (783 and 772 g head-1, respectively) compared to Vermi amended soil (663 g head-1). Yield obtained from lettuce variety Romaine was superior (1.2 kg head-1) compared to Bibb and Butterhead varieties (0.51 and 0.49 kg head-1, respectively). Watermelons yield obtained from CM treatment was significantly greater (4.49 kg fruit-1) than that of NM control treatment (3 kg fruit-1). In addition, variety Charleston Grey produced the greatest fruit weight (4.9 kg fruit-1) compared to Crimson and Sugar Baby (3.26 and 3.06 kg fruit-1, respectively). Pumpkin yield obtained from SS treatment was significantly greater (4.4 kg fruit-1) than that of NM treatment (3.6 kg fruit-1). Pumpkin variety Howden produced the greatest pumpkin fruit weight (4.6 kg fruit-1) compared to Renegade and Gumdrop varieties (4.1 and 3.3 kg fruit-1, respectively). Soil properties fluctuated among treatments. The NO3 -N values were greater in HM and Vermi treatments, whereas NH4-N was greater in SS and CM treatments compared to the control. No significant differences were found in phosphorus content among treatments. Concentrations of K and C (557 and 1230 µg g-1 dry soil, respectively) were significantly greater in Vermi compared to the control treatments (336 and 1091 µg g-1 dry soil, respectively). Vermi increased soil urease activity compared to other treatments. All amendments tested increased soil invertase activity. Whereas CM increased alkaline phosphatase activity. These results combine information to crop producers looking for cost-effective organic fertilizers to meet the market needs.

Cultivos de cobertura como antecesor de zapallo anco en la región semiárida pampeana

The objective was determine the effect of cover crops on the water use efficiency and total yield of the pumpkin crop. The study was carried out on a soil called petrocalcic Paleustoll, located in the south of the rugged plain of the semi­arid Pampa region. In the same lot for three consecutive seasons, Rye (C) and rye + vetch (CV) were sown and fallow was established without cover cultivation. In this way, 6 management treatments for pumpkin cultivation were established: T1: without CC predecessor, with tillage prior to pumpkin planting, and without weed control during the pumpkin cycle. T 2: without predecessor CC with tillage prior to planting the pumpkin, with weed control (tillage and herbicide), during the pumpkin cycle. C H: Rye ancestor used as CC, with growth arrest by herbicide. C R: Rye ancestor used as CC, with growth arrest by rolling. CV H: Rye + Vetch ancestor used as CC, with growth arrest by herbicide. CV R: Rye + Vetch ancestor used as CC, with growth arrest by rolling. The results showed that on average in the 3 seasons C was higher than C V, in 22, 19 and 6% with respect to the total biomass, for the first, second and third seasons, respectively. Cover crops had higher fallow efficiency with respect to treatments without prior CC (T1 and T2). The highest pumpkin yields were over the CC, these being the ones with the lowest UC and the highest EUAt

Effect of Seed Meals on Weed Control and Soil Physical Properties in Direct-Seeded Pumpkin

Mustard (Brassica sp.) seed meal (MSM) and sunflower (Helianthus annuus L.) seed meal (SSM) are the byproducts of the seed oil extraction process. They release biologically active allelochemicals that can provide a resource for supplemental nutrients and weed suppression in vegetable cropping systems. Our field experiment aimed to assess the phytotoxic impact of MSM and SSM on weeds and seedling establishment of direct-seeded pumpkin under semi-arid conditions and to study the impact of MSM and SSM on soil physical properties and soil water retention characteristics. The meals were incorporated into the soil 2 weeks before pumpkin planting at two rates (1150 and 2250 kg ha−1). MSM at both rates reduced early season grass and broadleaf weeds by 75 to 82% and 69 to 76%, respectively, as compared to the untreated control. However, SSM at both rates provided 59 to 65% and 54 to 59% controls of narrow and broadleaf weeds, respectively. Both MSM and SSM provided significantly better weed control and pumpkin yield as compared to the untreated control, but higher pumpkin yield was recorded with a lower rate of MSM. In addition, soils amended by both the seed meals had higher saturated hydraulic conductivity, soil water content, and lower bulk density than the untreated control. Overall, our findings suggest that the use of both MSM and SSM as an organic adjuvant is effective in controlling weeds and improving soil physical properties; however, additional research is required to further evaluate these findings and improve the reliability of MSM and SSM for weed suppression following application to agricultural soils.

Response of Pumpkin to Different Concentrations and Forms of Selenium and Iodine, and their Combinations.

The elements selenium (Se) and iodine (I) are both crucial for the normal functioning of the thyroid. Biofortification with these elements is particularly feasible in areas where they show a deficit. Iodine and selenium can have positive effects on different plants when applied at the correct concentrations. The effects of their simultaneous addition on plant physiology and biochemistry, as well as on seed germination and sprout biomass, were studied in pumpkin (Cucurbita pepo L. ssp. pepo). To study the effect of Se and I on sprouts, sprouts were grown from seeds soaked in solutions of different forms of Se, I and their combination in the growth chamber experiment. In the field experiment, pumpkins plants were foliarly treated with the same concentrations and forms of Se and I. The combination of Se and I treatments enhanced the germination of the soaked seeds, with no significant differences between Se and I treatments for sprout mass. The yield of pumpkins and seed production were unaffected by Se and I foliar application. The anthocyanin levels and respiratory potential measured via the electron transport system’s activity showed different patterns according to treatments and plant parts (sprouts, leaves, seeds). The redistribution of Se and I from seeds to sprouts was significant. The accumulation of Se was higher in sprouts from the seeds treated with Se together with I, compared to sprouts from the seeds treated with Se alone. Interactions between Se and I were also noted in the seeds, which developed in the treated plants.

Weed Pressure, Yield, and Adhesion of Soil-biodegradable Mulches with Pie Pumpkin (Cucurbita pepo)

A soil-biodegradable mulch (BDM) is designed to be tilled into the soil at the end of the growing season, and is a successful alternative to polyethylene (PE) mulch if it suppresses weeds and improves soil temperature and moisture, crop yield, and fruit quality. This study compared one clear plastic BDM (COX), two black plastic BDMs (BOX and BFO), and two paper BDMs (WGP and AMX) to clear and black plastic PE mulch (CPE and BPE, respectively) for weed control, yield, and mulch adhesion of ‘Cinnamon Girl’ pie pumpkin (Cucurbita pepo) in a Mediterranean climate where increased soil temperature from mulch is desirable. BDMs in this study are advertised as soil-biodegradable, and we tested functionality but not biodegradability. Mulch deterioration during the growing season was measured as percent soil exposure (PSE), and remained low at the end of the growing season for all BDM and PE treatments both years (5% on average) except COX (68%). Weed number and biomass were low early, mid, and late season for all treatments except COX in 2018 and COX and CPE in 2019. Soil temperature with PE mulches (20.7 °C on average) was similar or slightly higher than with plastic BDMs (19.8 °C on average), which was higher than with paper BDMs (18.9 °C on average). Total fruit number and yield were similar for PE mulches (19.3 and 24.5 kg, respectively) and black plastic BDMs (17.3 and 21.2 kg, respectively), which were higher than COX and paper BDMs (15.7 and 19.8 kg, respectively). Mulch adhesion occurred on fruit in all BDM treatments, with more mulch adhesion in BFO in 2018 and WGP in 2019 than in other BDM treatments each year. The number of wipes is a proxy for the impact on harvest labor and can influence overall on-farm profitability. The number of wipes to remove adhered mulch (1.2 wipes on average) was similar for fruit harvested at four times of day (0800, 1000, 1200, and 1400 hr), but more wipes were needed to remove adhered mulch when fruit were stored up to 4 hours postharvest (5.4 wipes). Number of wipes to remove adhered mulch was negatively correlated to the amount of moisture on the fruit surface (R2 = 0.31). Overall, these findings demonstrate that all black plastic and paper BDMs remained intact throughout the growing season and controlled weeds as well as black PE mulch, while clear BDM had higher weed pressure because it degraded during the growing season. Pumpkin yield was similar for black plastic BDMs and PE mulches and lower for clear and paper BDMs. However, all BDMs in this study adhered to the fruit surface and their removal became more difficult as the fruit surface dried.

Influence of Soil Amendment Practices on Soil Physicochemical Properties, Growths and Edible Leaf Yield of Fluted Pumpkin (Telfairia occidentalis) in Enugu South Eastern Area of Nigeria

The effect of inorganic fertilizer (NPK 15-15-15), mulching materials (plant residue), poultry manure (droppings) and lime (CaCO3) on soil physicochemical properties, growth and edible leaf yield of fluted pumpkin it was studied in 2019 in farming seasons at the Teaching and Research Farm of the Faculty of Agriculture and Natural Resources Management Enugu State University of Science and Technology. A Randomized Complete Block Design with five (5) treatments and four (4) replications were used for the experiment. The result of this experiment showed that inorganic fertilizer (NPK 15-15-15), produced significantly (P=0.05) 250 kg/ha, increased leaf area index (LAI), higher number of branches, highest fresh weight and gave longer vine length than line (CaCO3) 250 kg/ha, mulching materials (plant residue) 250 kg/ha and poultry manure (droppings) 250 kg/ha.

Pumpkin Yield Affected by Soil Nutrients and the Interactions of Nitrogen, Phosphorus, and Potassium Fertilizers

To study the effects of nitrogen (N), phosphorus (P), and potassium (K) fertilizers on the yield of ‘Jianbao’ pumpkin (Cucurbita maxima Duch), we conducted experiments using the “3414” optimal design scheme in Dehua County, Quanzhou, Fujian, China. Overall, three fertilizer factors (N, P, K) were tested with four fertilization levels (level 0, no fertilizer; level 1, 0.5-times the typical fertilizing amount; level 2, typical fertilizer application; level 3, 1.5-times the typical application), with a total of 14 different fertilization treatments. Based on the results of this study, a corresponding fertilization performance model was established to provide a practical basis for ensuring highly efficient cultivation of pumpkin in the field. Our results showed that the experimental data could not be fitted with a ternary quadratic polynomial fertilizer model, but that it could be fitted with a single-variable quadratic fertilizer model. According to the fitted model, pumpkin yield first increased and then decreased with the increasing amount of N, P, and K used. We identified significant regression relationships between ‘Jianbao’ pumpkin yield and the amount of N, P, and K in the fertilizer. Finally, based on the single-variable quadratic fertilizer model, we suggest that the quantities of N, P, and K fertilizer used for growing 1 ha of ‘Jianbao’ pumpkin should be 390.5, 213.8, and 371.3 kg, respectively.

The Effects of Different Plant Activators on Fruit and Seed Yield and Properties of Snack Pumpkin (Cucurbita pepo L.)

Pumpkin consists of the species of the genus Cucurbita in the Cucurbitaceae family. C. pepo and rarely C. moschata species are using as snack seeds growing in Turkey. This study was carried out to examine the effects of different plant activators on the fruit and seed yield and quality of the snack pumpkin which is observed in Cukurova University Pozanti Agricultural Research and Application Center, during 2015 and 2016 growing years. Crop-set (CR), Effective microorganisms (EM1), Endoroots soluble (ERS), Vitormone-Plus Drip (VIT), Bacillus subtilis OSU 142, Bacillus megatorium M3, Azospirillum sp. SP 245, Spirulina platensis (SIP) were used as plant activators. Ecocompost (ECO), Camli Botanica liquid organic fertilizer (BOT) and Zincon (ZIN) were used as organic fertilizer. Organic fertilizer (OF) and conventional fertilizer application (CONV.) were determined as the control group. In the experiment, the plant activators were applied to the plants alone, in combination with each other and with organic fertilizer. As a result of the study, the best result in fruit and seed yield in the snack pumpkin obtained from the applications in combination with organic fertilizers of plant activators. The highest value, fruits diameter, fruit length, fruit circumference were obtained from CONV. application. Finally, the best results in seed width, seed length and seed length/width ratio were obtained from organic fertilizer and EM1 + OG application. Keywords: Snack pumpkin, plant activators, yield DOI: 10.7176/JSTR/5-10-01

The effect of horn-manure preparation on enzymes activity and nutrient contents in soil as well as great pumpkin yield

Abstract This investigation was inspired by an increasing global issue on how to improve soil quality while using alternative preparations instead of synthetic fertilizers. The main aim of a three-year study was to investigate the influence of horn-manure preparation on enzyme activity and nutrient content in soil and pumpkin yield. The results showed that significantly higher amounts of P (respectively 106 and 79 mg kg−1 CAL), K (149 and 106 mg kg−1 CAL), nitrogen (5.41 and 3.21 mg kg−1), ammoniacal nitrogen (9.38 and 3.45 mg kg−1) and mineral nitrogen (7.97 and 5.67 mg kg−1) were measured in the plots where the horn-manure preparation was used. A higher activity of the soil enzymes (urease activity was 1.93 times higher and the saccharase activity was 1.05 times higher) were identified with horn-manure. The average soil CO2 flux (Fc) value, when using horn-manure preparation (from 56 till 70 day), was significantly higher by 5.32% in the middle of the growing season. The yield of pumpkin was significantly increased by 18% with horn manure treatments. Significant positive correlations were identified between pumpkin yield and urease activity, and saccharase activity, as well as soil P and K.

Yield and quality parameters of Hokkaido type pumpkins grown in Serbia

The aim of this study was to assess a set of 40 accessions of Hokkaido type pumpkins (Cucurbita maxima Duchesne) in terms of the traits of agronomic importance and the basic fruit flesh quality parameters, with the emphasis on Serbian environmental conditions. The pumpkins are a part of the larger Cucurbita collection belonging to the Institute of Field and Vegetable Crops from Novi Sad, where the two-year (2016, 2017) field trial was conducted. The accessions significantly differed in all analyzed parameters. The average values for the traits of agronomic importance were: yield per plant 3.56 kg, fruit weight 1.84 kg, number of fruits per plant 2.03, and anthesis date 180.29. Length of the main stem was in most cases short. Among fruit flesh quality parameters; the average dry weight content was 11.49%, sugars content 43.32 mg/g fresh weight, carotenoids content 50.12 mg/kg fresh weight, proteins content 4.04 mg/g fresh weight, total soluble solids content 8.63 ?Brix, refractive index 1.347, and pH 6.98. The highest coefficients of variation for agronomic and quality traits were those calculated for yield per plant and carotenoids content. The pumpkins performed better in the first season of the experiment due to more favorable weather, firstly temperature, conditions. The most pronounced adverse effect of high temperatures occurring in 2017 was the one expressed on the content of carotenoids, which was on average 48.4% lower when compared to 2016. Principal component analysis was employed to clarify the relationships among the investigated parameters, and to distinguish those with the most important contribution to the pumpkin variability. The analysis revealed strong correlations among yield per plant, fruit weight and length of the main stem. Carotenoids content and pH also correlated to yield, while the other quality parameters correlated to each other. Defining both first and second principal components, yield per plant and fruit weight were the parameters with the highest contribution to the variability among the assessed pumpkins. Concerning quality parameters, fruit flesh dry weight contributed the most to the variability. Therefore, the strategy for breeding Hokkaido type pumpkins adapted to Serbian environmental conditions should be based on combining irrespectively selected high-yield and high-quality accessions.

Can biochar improve pumpkin productivity and its physiological characteristics under reduced irrigation regimes?

Water stress is one of the main constraints which could limits crop productivity, especially in the arid regions. This study hypothesized that the combination of biochar amendments could be a part of sustainable agricultural strategy in semi-arid environment, therefore the objective was to investigate the effects of biochar rates under different irrigation regimes on soil properties, physiology and yield of pumpkin (Cucurbita pepo L.). The experiment was conducted in Gorgan (Iran) in two successive years (2014 and 2015) and consisted of a factorial combination of four irrigation regimes [45%, 60%, 75% and 90% (called I1, I2, I3 and I4, respectively) of maximum allowable depletion (MAD) of available soil water (ASW)] with four rates of biochar derived from maize-straw feedstock [0, 5, 10 and 20 t biochar ha−1 (called B0 B5, B10 and B20, respectively)]. The results indicated that the incorporation of biochar into the soil increased both soil permeability (low bulk density and high pore volume) and the water holding capacity, particularly when biochar was applied at the rate of 20 t ha−1. Moreover, after pumpkin cultivation, the B20 showed high soil microbial biomass carbon. The reduction of irrigation water increased the activity of antioxidant enzymes, the content of malondialdehyde (MDA), oxygen radicals (O2−), and hydrogen peroxide (H2O2) in pumpkin leaves, while all the antioxidant activities and proline contents declined on pumpkin plant treated with biochar, especially at the highest rate (B20). The adoption of biochar as amendment increased chlorophyll content and the uptake of nutrients in leaves regardless of irrigation regimes. The seed yield showed a decrease of 6%, 46% and 58% in I2, I3 and I4, respectively, in comparison with I1 regardless of biochar rate. Response rate to biochar was ceased in lower biochar rates by prolonging irrigation, but I2 response to biochar ceased in higher biochar rate as Bcritical (14 t biochar ha−1). This implies that I2 irrigation regime improved response of pumpkin to biochar, which was accompanied by its high WUE. These results indicate that biochar amendment could provide a suitable strategy for improving the physical status of agricultural soils, water use efficiency and vegetable crop yield.

Yield and horticultural performance of seed-oil pumpkin in south Florida

Naked seeds derived from ‘naked-seed’ pumpkin (Cucurbita pepo L.) are a popular ingredient in many snacks, breads, breakfast cereal, soups and other edible goods (Baxter et al. 2012; Loy 2004). Vegetable oil derived from the seed can be purchased by the bottle for culinary/ condiment use or as formulated capsules in health food stores (Stevenson et al. 2007). Unlike conventional hulled pumpkin seeds, naked seeds lack a complete seed coat, thus are preferred for snacking and oil production because they eliminate the need for manual de-hulling prior to use. Popularity of naked seed products is expected to increase in the US as the market for healthy foods increases. Pumpkin seed is rich in oil (50% w/w), protein (35%), unsaturated fatty acids (86%) (Meru et al. 2018), and antioxidants that have many health benefits, including a reduced risk of certain cancers (Lelley et al. 2009; Nesaretnam et al. 2007; Stevenson et al. 2007), treatment of enlarged prostate, and lowering cholesterol levels (Fruhwirth and Hermetter 2007; Thompson and Grundy 2005). Despite growing popularity of pumpkin seeds in the US, a majority of naked seeds consumed in the US is imported; hence, the need to identify/ develop cultivars adapted to local growing conditions. This article reports yield and horticultural performance of two ‘naked-seed’ pumpkin cultivars under south Florida (Miami-Dade County) spring growing conditions.

Effect of Paclobutrazol and NAA on Sex determination and Seed Yield of Medicinal Pumpkin (Cucurbıta pepo L.)

In order to evaluate the effect of plant growth regulators on sex determination and yield, an experiment was conducted by spraying different hormonal combinations on medicinal pumpkin. Experimental treatments were included different concentrations of NAA (25, 75, 100, 125 mg/l), paclobutrazol (50, 100, 200 and 300 mg/l) and combination of growth regulators (NAA 25 mg/l + PBZ 50 mg/l), (NAA 75 mg/l + PBZ 100 mg/l), (NAA 100 mg/l + PBZ 200 mg/l), (NAA 125 mg/l + PBZ 300 mg/l), and control (no application of growth regulators). Growth regulators were applied on the plants by spraying at the –two-leaf and four-leaf stages. Results showed that spraying paclobutrazol and NAA caused increase in number of female flowers, fruits per plant, seeds per fruits, 1000 seed weight and seed yield per hectare, but the number of male flowers and ratio of male to female flowers were decreased compared to their values in control plants. The highest fresh and dried seed yield of pumpkin seed was obtained with 50 mg/l paclobutrazol.

The response of plants and crops of white Pumpkins (Legeneria leucantha) Manisa Variety, un the provision cow manure and NPK Pearls fertilizer

Objective of the study is to determinate the effect of cow manure and NPK Pearls fertilizer and their interaction on the growth and yield of white pumpkin (Legeneria leucantha) Manisa variety. The research was conducted from March 2016 t0 June 2016, in Segoy Makmur, Sub Districd Long Mesangat, Wesh kutai Regency, East Kalimantan Province.The study design used a 4x4 factorial experiment in a Completely Randomized Group (CRG), and repeated 4 times. The first factor is the cow manure (K), consisting of four levels namely ; no cow manure fertilizer application (k0), dose 5 ton ha-1 equivalent to 50 g/plants-1 (k1), dose 10 ton ha-1 equivalent to 100 g/plants-1 (k2), dose 15 ton ha-1 equivalent to 150 g/plants-1 (k3). The second factorial is the application of NPK Pearls fertilizer (N), consisting of four levels namely ; no NPK Pearls fertilizer application (k0), dose 200 kg/ha-1 equivalent to 2,00 g/plant-1 (n1), dose 300 kg/ha-1 equivalent to 3,00 g/plant-1 (n2), dose 400 kg/ha-1 equivalent to 4,00 g/plant-1 (n3).Manure application not significant on plant height, aged 20, 40, and 60 days after planting, and significantly different to the age of the plant at planting, but highly significant of the life of the current crop of fruit, fruit number and weight of the fruit crop planting. Reseach results show that the treatment, NPK pearl very, significant effect of plant height at 20, 40, and 60 days after planting, and no real effect on the age of the plant during flowering, fruiting age of the of the current crop, planting fruit number and weight of the fruit crop. Application between cow manure and fertilizers NPK pearl effect no significant effect on plant height at 20, 40, and 60 days after planting during flowering, the age of the current per plant, and weight of fruit per plant.

The Use of Biodegradable Mulches in Pie Pumpkin Crop Production in Two Diverse Climates

The use of plastic biodegradable mulch (BDM) in many vegetable crops such as tomato (Solanum lycopersicum L.), broccoli (Brassica oleracea L. var. italica), and pepper (Capsicum annuum L.) has been proven to be of equal benefit as polyethylene (PE) mulch. However, there are limited research findings on the performance of BDM with a large fruited crop such as pumpkin (Cucurbita pepo L.) where the fruit can rest directly on the mulch for an extended period. To investigate whether heavy fruit might cause the mulch to degrade more quickly than expected, thereby, influencing weed control, fruit yield, and fruit quality including mulch adhesion on fruit, we carried out a field experiment in 2015 and 2016 at two locations in the United States with distinctive climates, Mount Vernon, WA and Knoxville, TN. Three plastic mulches marketed as biodegradable (BioAgri, Organix, and Naturecycle), one fully biodegradable paper mulch (WeedGuardPlus), and one experimental plastic BDM consisting of polylactic acid and polyhydroxyalkanoates (Exp. PLA/PHA) were evaluated against PE mulch and bare ground where ‘Cinnamon Girl’ pie pumpkin was the test crop. There was significant weed pressure in the bare ground plots at both locations over both years, indicating viable weed seed banks at the field sites. Even so, weed pressure was minimal across mulch treatments at both locations over both years because the mulches remained sufficiently intact during the growing season. The exceptions were Naturecycle in 2015 at both locations because of the splitting of the mulch and consequently higher percent soil exposure (PSE), and the penetration of all the plastic mulches at Knoxville by nutsedge (Cyperus sp. L.); nutsedge did not penetrate WeedGuardPlus. At Mount Vernon, overall pumpkin yield across both years averaged 18.1 t·ha−1, and pumpkin yield was the greatest with PE, Exp. PLA/PHA, BioAgri, and Naturecycle (19.9–22.8 t·ha−1), intermediate with Organix and WeedGuardPlus (15.3–18.4 t·ha−1), and the lowest for bare ground (8.7 t·ha−1). At Knoxville, overall pumpkin yield across both years averaged 17.7 t·ha−1, and pumpkin yield did not differ because of treatment (15.3–20.4 t·ha−1). The differences in yield between treatments at Mount Vernon were likely because of differences in the soil temperature. At 10 cm depth, the average soil temperature was 1 °C lower for bare ground and WeedGuardPlus as compared with PE mulch and plastic BDMs (20.8 °C). In contrast, soil temperatures were generally higher (25.2 to 28.3 °C) for all treatments at Knoxville and more favorable to crop yield compared with Mount Vernon. Forty-two percent to 59% of pumpkin fruit had mulch adhesion at harvest at Mount Vernon, whereas only 3% to 12% of fruit had mulch adhesion at Knoxville. This difference was because of the location of fruit set—at Mount Vernon, most of the fruit set was on the mulch whereas at Knoxville, vine growth was more extensive and fruit set was mostly in row alleys. Fruit quality differences among treatments were minimal during storage across both locations and years except for total soluble solids (TSS) in 2016, which was lower for bare ground and WeedGuardPlus compared with all the plastic mulches. Taken overall, these results indicate that pie pumpkin grown with BDM has fruit yield and quality comparable to PE mulch; however, adhesion of some BDMs on fruit could affect marketable yield. Furthermore, paper mulch appears to prevent nutsedge penetration.

Intercropping short duration leafy vegetables with pumpkin in subtropical alluvial soils of Bangladesh

Intercropping may allow increasing both the productivity and diversity of crop through efficient utilization of land in densely populated countries like Bangladesh where fertility of agricultural land is declining gradually. A field experiment was conducted at a recently developed alluvial soil in Bangladesh during 2015–16 and 2016–17 winter seasons to select suitable leafy vegetables intercropping with pumpkin for higher productivity, better land and time utilization and maximum economic return. Six leafy vegetables viz., coriander green, red amaranth, radish green, mustard green, jute green, and spinach were intercropped with pumpkin and compared with sole pumpkin using a randomised complete block design. Intercropping leafy vegetables with pumpkin did not reduce pumpkin yield but increased system productivity by 39–120% over sole cropped pumpkin. All the intercropping combinations performed better than sole pumpkin. However, the highest system yield (72.7 & 75.6 t ha–1), land equivalent ratio (1.74 & 1.75), area time equivalent ratio (1.20 & 1.16), net return (8001 & 8350 USD ha–1) and benefit cost ratio (10.3 & 10.7) were obtained in 2015–16 & 2016–17, respectively from pumpkin + spinach system indicating that this system might be suitable for higher crop productivity, better land and time utilization as well as economic return for the selected area.

Yield performance and agronomic efficiency in oil pumpkins (Cucurbita pepo L. group Pepo) depending on production systems and varieties

AbstractIn 2013 and 2014, a long-term trial (which was established in 2007) was conducted at the University Agricultural Centre in Pivola near Hoče. It included different production systems (conventional, integrated, organic, biodynamic), carried out in a field trial with oil pumpkins. The aim of the research was to analyse the effects of different production systems, varieties (hybrid and population variety) and years of production, on formation of oil pumpkin yields. The agricultural practice has been carried out in accordance with the applicable legislations and standards for the individual production system. When sowing, before fertilizing with nitrogen in early June and after the harvest, the amount of soil mineral nitrogen was monitored. We evaluated the number and weight of harvestable, unripe and decayed fruits, and yield of oil seed pumpkins and calculated the agronomic efficiency of the applied nutrients. The results showed that the year of production, the production system and the variety have a significant effect on some fruit characteristics and the yield of oil pumpkin seeds. The content of soil mineral nitrogen in May and September was significantly influenced by the production system and the year. In June, only the production system had a significant effect. The hybrid significantly increased the yields of oil pumpkin seeds in all production systems, even in the year that was less suitable for production. The agronomic efficiency of the applied nutrients in the biodynamic and organic production system is higher or equal than in the conventional production system, similarly, agronomic efficiency is higher in the hybrid compared to the oldest population variety efficiently. A comparable oil pumpkin yield can be expected in biodynamic and organic production, when proper nutrition and well carried out cultivation practices are combined with a new variety, when compared to less sustainable production systems, which often cause damage to the environment.

Effect of Cattle Manure and Sulfur on Yield and Oil Composition of Pumpkin (Cucurbita pepo var. Styriaca) Inoculated with Thiobacillus thiooxidans in Calcareous Soil

ABSTRACTThe effect of cattle manure and sulfur fertilizer on seed yield and oil composition of pumpkin (Cucurbita pepo var. Styriaca) under inoculated with Thiobacillus thiooxidans was investigated in a factorial study based on a randomized complete block design. Experimental factors consisted of cattle manure (M) (M0: 0, M1: 10; and M2: 20 t ha−1), sulfur (S) (S0: 0, S1: 250; and S2: 500 kg ha−1) and T. thiooxidans (B): inoculated (B1) and non-inoculated (B0). Results demonstrated that the application of T. thiooxidans, cattle manure, and S fertilizer decreased the soil pH. The largest number of seed per fruit (367), highest fruit yield (70.57 t ha−1), seed iron (Fe) content (16.26 mg 100 g−1), and seed yield (111 kg ha−1) was obtained when 20 t ha−1 manure was applied in combination with 500 kg ha−1 S inoculated with T. thiooxidans. In this condition, the content of S, Fe, phosphorus (P), and nitrogen (N) in plant shoots was increased by 44.8%, 22.58%, 33.89%, and 10.38%, respectively, compared to the control. Moreover, the highest content of seed protein was observed in 10 t ha−1 manure and 500 kg ha−1 S fertilizer inoculated with T. thiooxidans. When 250 kg ha−1 S fertilizer was applied, 20 t ha−1 manure decreased seed P content sharply. At the rate of 500 kg ha−1 S fertilizer, the highest content of seed P was obtained from 20 t ha−1 manure. Totally, 20 t ha−1 cattle manure, along with 500 kg ha−1 S fertilizer as well as T. thiooxidans inoculation, improved oil and seed yield of medicinal pumpkin.

Sensitivity of commercial pumpkin yield to potential decline among different groups of pollinating bees.

The yield of animal-pollinated crops is threatened by bee declines, but its precise sensitivity is poorly known. We therefore determined the yield dependence of Hokkaido pumpkin in Germany on insect pollination by quantifying: (i) the relationship between pollen receipt and fruit set and (ii) the cumulative pollen deposition of each pollinator group. We found that approximately 2500 pollen grains per flower were needed to maximize fruit set. At the measured rates of flower visitation, we estimated that bumblebees (21 visits/flower lifetime, 864 grains/visit) or honeybees (123 visits, 260 grains) could individually achieve maximum crop yield, whereas halictid bees are ineffective (11 visits, 16 grains). The pollinator fauna was capable of delivering 20 times the necessary amount of pollen. We therefore estimate that pumpkin yield was not pollination-limited in our study region and that it is currently fairly resilient to single declines of honeybees or wild bumblebees.