Combined Effects of Ventilation and Irrigation on Temperature, Humidity, Tomato Yield, and Quality in the Greenhouse

Ventilation and soil moisture influence greenhouse cultivation. Experiments were conducted at Xinxiang Irrigation Research Base of the Chinese Academy of Agricultural Sciences, Henan Province, China, to identify how ventilation and irrigation affected the greenhouse microenvironment. To develop ventilation and irrigation protocols that increase crop yield and improve the quality of drip-irrigated tomatoes grown in the greenhouse, three ventilation modes (T1, T2, and T3) were developed by opening vents in different locations in a completely randomized pattern. T1 had open vents on the north wall and roof of the greenhouse. T2 had open vents on the north and south walls and the roof. T3 had open vents on the north and south walls. Three irrigation treatments (W1, W2, and W3) were designed based on the accumulated water surface evaporation (Ep) of a standard 20-cm evaporation pan. The irrigation quantities were 0.9×Ep (W1), 0.7×Ep (W2), and 0.5×Ep (W3). The spatial and temporal distributions of temperature and humidity were analyzed for different combinations of ventilation and irrigation to identify their effects on tomato yield and fruit quality. Major results were as follows: 1) In addition to solar radiation, ventilation had an important influence on Ep and, on a daily scale, ventilation had a significant effect on Ep (P < 0.05). 2) Ventilation had a significant effect on indoor wind speed, but the effect varied during different growth stages. During the flowering and fruit setting stage, wind speed for T2 significantly differed from those of T1 and T3 (P < 0.01). During the harvest stage, the three ventilation treatments had significantly different effects (P < 0.01). A correlation analysis showed high correlation between T2 wind speed and T3 wind speed (R = 0.831), but low correlation between T2 wind speed and T1 wind speed (R = 0.467). 3) The effect of ventilation on greenhouse humidity and temperature was greater than the effect of irrigation. The differences in air temperature among various combined treatments of ventilation and irrigation were significant for the flowering and fruiting stages (P < 0.05), but they were not significant for the late harvest stage (P > 0.05). There were significant differences in humidity on sunny days (P < 0.01), but no significant differences on cloudy or rainy days (P > 0.05). Air temperature at 2 m was greater than canopy temperature, but humidity at 2 m was less than that at canopy level. 4) Irrigation water quantity was positively correlated with tomato yield and negatively correlated with the fruit quality indicators total soluble solids, vitamin C content, organic acid content, and soluble sugars content. Ventilation had an effect primarily during the harvest period; it had no significant effect on yield (P > 0.05). However, it had a significant effect on vitamin C content and the sugar:acid ratio (P < 0.01). The combination treatment of T2W2 is recommended as the optimal treatment for greenhouse tomatoes using drip irrigation to produce an optimal combination of crop yield and fruit quality. This study provides theoretical and technical support for the improvement of greenhouse climate control by optimizing greenhouse ventilation and irrigation techniques to promote tomato yield and improve fruit quality.

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Potential Evapotranspiration Reduction and Its Influence on Crop Yield in the North China Plain in 1961–2014

Advances in Meteorology ◽

10.1155/2020/3691421 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Wanlin Dong ◽

Chao Li ◽

Qi Hu ◽

Feifei Pan ◽

Jyoti Bhandari ◽

...

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Crop Yield ◽

North China Plain ◽

North China ◽

Potential Evapotranspiration ◽

The North ◽

The North China Plain ◽

Sunshine Hours ◽

Humidity Index

Climate change has caused uneven changes in hydrological processes (precipitation and evapotranspiration) on a space-temporal scale, which would influence climate types, eventually impact agricultural production. Based on data from 61 meteorological stations from 1961 to 2014 in the North China Plain (NCP), the spatiotemporal characteristics of climate variables, such as humidity index, precipitation, and potential evapotranspiration (ET0), were analyzed. The sensitivity coefficients and contribution rates were applied to ET0. The NCP has experienced a semiarid to humid climate from north to south due to the significant decline of ET0 (−13.8 mm decade−1). In the study region, 71.0% of the sites showed a “pan evaporation paradox” phenomenon. Relative humidity had the most negative influence on ET0, while wind speed, sunshine hours, and air temperature had a positive effect on ET0. Wind speed and sunshine hours contributed the most to the spatiotemporal variation of ET0, followed by relative humidity and air temperature. Overall, the key climate factor impacting ET0 was wind speed decline in the NCP, particularly in Beijing and Tianjin. The crop yield in Shandong and Henan provinces was higher than that in the other regions with a higher humidity index. The lower the humidity index in Hebei province, the lower the crop yield. Therefore, potential water shortages and water conflict should be considered in the future because of spatiotemporal humidity variations in the NCP.

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Changes in the Biochemical Composition of Tomato Fruit under the Influence of Illumination Quality

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.850.172 ◽

2020 ◽

Vol 850 ◽

pp. 172-178

Author(s):

Ieva Erdberga ◽

Ina Alsina ◽

Laila Dubova ◽

Māra Dūma ◽

Daiga Sergejeva ◽

...

Keyword(s):

High Pressure ◽

Vitamin C ◽

Organic Acids ◽

Biochemical Composition ◽

Biochemical Parameters ◽

Tomato Fruit ◽

Soluble Sugars ◽

Winter Season ◽

Biologically Active ◽

Tomato Yield

Tomatoes are one of the most consumed vegetables in the world. Unfortunately, obtaining a high quality tomato yield in our latitudes is inconceivable without additional lighting. Changes in biochemical composition are mainly dependent on the light received by the plant. During the winter months, natural daylight at 55 ° latitude is insufficient to provide the necessary vegetation for fruit-bearing vegetables. The aim of this study is to investigate the changes in the biochemical composition of tomato fruits by using less conventional lighting methods, which could offer potential energy savings by providing higher levels of biologically active substances in tomatoes. The study was conducted in a greenhouse of Latvia University of Life Sciences and Technologies during the winter season 2018-2019, using a 16-hour photoperiod. LED, Induction, and High Pressure Sodium Lamps (as control) were used in the study. These lighting devices, with some differences, simulate daylight. Three tomato cultivars: ‘Diamont F1’, Encor F1’and ‘Balzano F1’were studied. The study specified the tomato yield and the following biochemical parameters: soluble sugars (BRIX), vitamin C, organic acids, lycopene, carotenoids, phenols and flavonoids. As expected, the yield and species-specific pigment content of tomato fruit is largely dependent on the genetics of the variety. On the other hand, biologically active compounds such as organic acids, soluble sugars, ascorbic acid and flavonoids undergo more changes due to the composition of the light. The obtained biochemical parameters give an opportunity to consider different illumination methods and the need to carry out further studies in order to confirm the conclusions. Significantly higher yields were observed in the variant with conventionally used high pressure sodium lamps. In mean time, it should be noted that in the variant with LED lamps, higher content of lycopene as well as phenols and vitamin C were observed.

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Effects of Summer Pruning and Cropload on Summer and Winter Bud Carbohydrates in Sweet Cherry

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.139.4.478 ◽

2014 ◽

Vol 139 (4) ◽

pp. 478-486 ◽

Cited By ~ 1

Author(s):

Penelope F. Measham ◽

Audrey G. Quentin ◽

Nicholas MacNair

Keyword(s):

Fruit Quality ◽

Management Practices ◽

Sweet Cherry ◽

Prunus Avium ◽

Soluble Sugars ◽

Late Summer ◽

Growth Stages ◽

Bud Burst ◽

Storage Organs ◽

The Impact

Orchard management practices have the potential to influence carbohydrate supply to storage organs, including buds. This study was designed to assess if bud carbohydrates could be manipulated by orchard practices in sweet cherry (Prunus avium). Additionally, we investigated the impact of any such changes on subsequent bud burst and fruit quality the next season. We examined the effect of pruning at different fruit growth stages and cropload on summer and winter bud non-structural carbohydrates (NSCs) and on fruit quality at harvest the next summer in two cultivars. Buds were collected postharvest in summer and after the onset of dormancy in winter, and individual soluble sugars and starch were extracted. The next growing season, flower number and fruit set were recorded. When fruit reached full maturity, fruit were harvested for quality assessment. We observed qualitative changes in NSCs from buds collected in summer and winter. Pruning significantly reduced available NSCs in late summer buds but made little difference by winter; only early pruning showed slight changes in sucrose and glucose. However, early pruning positively influenced the next season’s fruit grade. High cropload resulted in higher NSCs in winter buds than the low cropload. Significant changes in sucrose from summer to winter were observed, and levels of sucrose in the buds differed between cultivars. Different levels of winter bud sucrose between cultivars corresponded to different rates of bud burst. Although pruning was able to manipulate NSCs in buds within a few weeks, these changes were not sufficient to influence the rate of bud burst within a cultivar, but pruning did influence fruit quality in the next season.

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(196) A Comparison of Fruit Quality and Antioxidant Properties of Alabama-grown Kiwi

HortScience ◽

10.21273/hortsci.41.4.1050d ◽

2006 ◽

Vol 41 (4) ◽

pp. 1050D-1050

Author(s):

Ming-Wei S. Kao ◽

Floyd Woods ◽

William A. Dozier ◽

Robert C. Ebel ◽

Chang Y. Lee ◽

...

Keyword(s):

Vitamin C ◽

Fruit Quality ◽

Radical Scavenging Activity ◽

Soluble Sugars ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Health Indicators ◽

Fresh Fruit ◽

Kiwi Fruit ◽

Antioxidant Power

The health status of Alabama's population ranks above the national average with respect to the prevalence of poor overall health indicators. Consumer knowledge of the health benefits of consumption of fresh fruit is lacking. The compositional and nutritional qualities of fruit are highly variable among states with different climate, soil, and other environmental conditions. Compositional and nutritional data of fresh fruit that reflect Alabama growing conditions is limited. Commercially fully ripened kiwi fruit (Actinidia deliciosa cvs. Fitzgerald and Hayward) were compared for fruit quality (pH, TA, °Brix, °Brix/TA, and soluble sugars), and antioxidant properties; Vitamin C (reduced, oxidized, and total), Vitamin C Equivalent Antioxidant Capacity (VCEAC), ferric reducing antioxidant power (FRAP), DPPH radical scavenging activity, total phenolics, and flavonoids. In general, `Fitzgerald' ranked higher in overall fruit quality and antioxidant properties when compared to `Hayward'.

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Impact of Selenium and Copper Nanoparticles on Yield, Antioxidant System, and Fruit Quality of Tomato Plants

Plants ◽

10.3390/plants8100355 ◽

2019 ◽

Vol 8 (10) ◽

pp. 355 ◽

Cited By ~ 12

Author(s):

Hernández-Hernández ◽

Quiterio-Gutiérrez ◽

Cadenas-Pliego ◽

Ortega-Ortiz ◽

Hernández-Fuentes ◽

...

Keyword(s):

Vitamin C ◽

Fruit Quality ◽

Tomato Fruit ◽

Titratable Acidity ◽

Good Alternative ◽

Soluble Solids ◽

Antioxidant Compounds ◽

Tomato Yield ◽

The Impact

The effects of nanoparticles (NPs) on plants are contrasting; these depend on the model plant, the synthesis of the nanoparticles (concentration, size, shape), and the forms of application (foliar, substrate, seeds). For this reason, the objective of this study was to report the impact of different concentrations of selenium (Se) and copper (Cu) NPs on yield, antioxidant capacity, and quality of tomato fruit. The different concentrations of Se and Cu NPs were applied to the substrate every 15 days (five applications). The yield was determined until day 102 after the transplant. Non-enzymatic and enzymatic antioxidant compounds were determined in the leaves and fruits as well as the fruit quality at harvest. The results indicate that tomato yield was increased by up to 21% with 10 mg L−1 of Se NPs. In leaves, Se and Cu NPs increased the content of chlorophyll, vitamin C, glutathione, 2,2′-azino-bis(3-ethylbenzthiazolin-6-sulfonic acid (ABTS), superoxide dismutase (SOD), glutathione peroxidase (GPX) and phenylalanine ammonia liasa (PAL). In fruits, they increased vitamin C, glutathione, flavonoids, firmness, total soluble solids, and titratable acidity. The combination of Se and Cu NPs at optimal concentrations could be a good alternative to improve tomato yield and quality, but more studies are needed to elucidate their effects more clearly.

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Evaluation of crop yield and fruit quality in organic apple production

International Journal of Horticultural Science ◽

10.31421/ijhs/13/1/686 ◽

2007 ◽

Vol 13 (1) ◽

Author(s):

I. Gonda ◽

N. Rakonczás ◽

I. J. Holb

Keyword(s):

Vitamin C ◽

Crop Yield ◽

Fruit Quality ◽

Sugar Content ◽

Quality Parameters ◽

Soluble Solids ◽

Total Acid ◽

Total Sugar Content ◽

Solids Concentration ◽

Apple Cultivars

In this study, crop yield and fruit quality parameters (soluble solid concentration, sugar, total acid, and vitamin C content) of 15 apple cultivars including old, resistant and currently grown cultivars. The highest fruit yield among all 15 cultivars was obtained on CV. Jonagold with 15.5 kg/tree, while the lowest yield was measured on the resistant cultivar Reanda with 8.1 kg/tree. There were no significant differences among the cultivars in fruit diameter ranging from 70 mm in the case of cv. Húsvéti rozmaring to 82 mm for cv. Mutsu. Values of soluble solids concentration of the cultivars varied between 15.5% for cv. Téli Banán and 19.2% for cv. Renora. Sugar content values showed a similar tendency to soluble solids content. The highest and lowest total sugar content was observed on cvs. Jonagold and Renora and cv. Retina with 17% and 12.4%, respectively. Total acid content values ranged between 0.18% and 0.53% for cvs. Jonagold and Remo, respectively. Values of vitamin C content for the 15 apple cultivars varied between 2 mg% and 4 mg% for cv. Retina and cv. Mutsu, respectively.

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Fertiliser nitrogen effects on hill pasture and on grazing by ewes

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.2004.66.2550 ◽

2004 ◽

pp. 163-169

Author(s):

A.G. Gillingham ◽

M.H. Gray ◽

S. Macmillan

Keyword(s):

Chemical Composition ◽

Soluble Sugars ◽

Grazing Intensity ◽

Seasonally Dry ◽

The North ◽

Grazing Intensities ◽

Grazing Period ◽

Fertiliser Application ◽

North And South ◽

Grazing Behaviour

A study was conducted on seasonally dry hill pastures near Waipawa, central Hawkes Bay, over a two year period to investigate how the application of nitrogen (N) fertiliser changed the pasture chemical and species composition and if animals subsequently preferentially grazed that pasture. In Year 1 the short term effects of N fertiliser (30 kg N/ha) was evaluated on both north and south facing slopes after the pasture was spelled for about 12 to 25 days only after N fertiliser application. This period did not allow sufficient time for pasture dry matter (DM) responses to develop. In Year 2, using the same trial sites, the pasture was allowed to develop DM response differences of 500 kg/ha or more following N fertiliser application before animals commenced grazing. On each occasion, grazing observations were made during a 5 hour period following stock introduction to spelled pasture. Herbage mass per plot was measured prior to, and at the end of the grazing period, and the amounts of pasture utilised per plot calculated. In Year 1 there were three separate measurements and grazing observations. The first was in mid winter on pasture with a high dead matter and near zero clover content and overall low quality. N fertiliser had no effect on chemical composition. In the second and third observations in late July and September respectively, when more clover and less dead matter was present, N and crude protein (CP) concentrations were both enhanced by earlier N fertiliser application. Similarly in 2003 when herbage mass responses were allowed to accumulate following N fertiliser application, the pasture N, phosphorus, potassium and CP levels all increased and soluble sugars and starch levels decreased. These effects were more pronounced in the pasture from the south than from the north aspect. In Year 1 there were no differences between Nfertilised and non-fertilised plots in mean grazing intensity (ewes/100m2), or in the amounts of pasture DM utilised during grazing. In Year 2, grazing intensities and the amounts of pasture utilised, were higher where pasture mass was significantly higher as a result of N fertiliser application. The results suggested that where significantly greater pasture DM responses are allowed to occur, the subsequent grazing intensities will also be greater compared with grazing intensities on associatedpasture. It is likely that the differences in pasture chemical composition induced by application of N fertiliser at 30 kg /ha were insufficient to cause any difference in grazing behaviour by ewes. Higher N fertiliser rates may be required to induce such chemical changes and grazing preferences as observed in other studies. Keywords: grazing intensity, nitrogen fertiliser, pasture quality, pasture species

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Optimization Assessment of Projection Methods of Climate Change for Discrepancies between North and South China

Water ◽

10.3390/w12113106 ◽

2020 ◽

Vol 12 (11) ◽

pp. 3106

Author(s):

Yurui Lun ◽

Liu Liu ◽

Ruotong Wang ◽

Guanhua Huang

Keyword(s):

Climate Change ◽

Air Temperature ◽

Statistical Downscaling ◽

Regional Climate ◽

Regional Climate Change ◽

Climate Zones ◽

Climate Change Projection ◽

The North ◽

North And South ◽

Selection Of

Downscaling methods have been widely used due to the coarse and biased outputs of general circulation models (GCMs), which cannot be applied directly in regional climate change projection. Hence, appropriate selection of GCMs and downscaling methods is important for assessing the impacts of climate change. To explicitly explore the influences of multi-GCMs and different downscaling methods on climate change projection in various climate zones, the Heihe River Basin (HRB) and the Zhanghe River Basin (ZRB) were selected in this study to represent the north arid region and the south humid region in China, respectively. We first evaluated the performance of multi-GCMs derived from Coupled Model Inter-comparison Project Phase 5 (CMIP5) in the two regions based on in-situ measurements and the 40 year European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40) data. Subsequently, to construct appropriate climate change projection techniques, comparative analysis using two statistical downscaling methods was performed with consideration of the significant north–south meteorological discrepancies. Consequently, specific projections of future climate change for 2021–2050 under three representative concentration pathway (RCP) scenarios (RCP2.6, RCP4.5, and RCP8.5) were completed for the HRB and ZRB, including daily precipitation, maximum air temperature, and minimum air temperature. The results demonstrated that the score-based method with multiple criteria for performance evaluation of multiple GCMs more accurately captured the spatio-temporal characteristics of the regional climate. The two statistical downscaling methods showed respective advantages in arid and humid regions. The statistical downscaling model (SDSM) showed more accurate prediction capacities for air temperature in the arid-climate HRB, whereas model output statistics (MOS) better captured the probability distribution of precipitation in the ZRB, which is characterized by a humid climate. According to the results obtained in this study, the selection of appropriate GCMs and downscaling methods for specific climate zones with different meteorological features significantly impact regional climate change projection. The statistical downscaling models developed and recommended for the north and south of China in this study provide scientific reference for sustainable water resource management subject to climate change.

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Flower-visiting insects on Solidago × Niederederi (Asteraceae): an observation from a domestic garden

Botanica ◽

10.2478/botlit-2018-0016 ◽

2018 ◽

Vol 24 (2) ◽

pp. 162-171 ◽

Cited By ~ 1

Author(s):

Artur Pliszko ◽

Kinga Kostrakiewicz-Gierałt

Keyword(s):

Wind Speed ◽

Air Temperature ◽

North American ◽

Natural Hybrid ◽

Positive Correlation ◽

The North ◽

The Future ◽

Flower Visiting

Abstract Pliszko A., Kostrakiewicz-Gierałt K., 2018: Flower-visiting insects on Solidago ×niederederi (Asteraceae): an observation from a domestic garden. - Botanica, 24(2): 162-171 In this study, we focused on flower-visiting insects on Solidago ×niederederi, a natural hybrid between the North American S. canadensis and the European S. virgaurea. Based on four-day observation in a domestic garden, we evidenced a high number of Diptera visits on hybrid flowers, per each hour of the recording, and a positive correlation between the number of insect visits and the length, the width and the number of secondary branches of synflorescence and the number of capitula. Moreover, the number of insect visits positively correlated with the air temperature and negatively correlated with the wind speed. The increasing number of insect visits with the increasing size of synflorescences suggests that capitula of the hybrid arranged in bigger panicles might be more visible and smell stronger. However, a high number of insect visits on the flowers within the same synflorescence may promote the occurrence of geitonogamy. The involvement of various insects in pollination of S. ×niederederi needs to be studied in the future.

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