Off-season Fruit Research Articles

High-quality off-season mulberry fruit (Morus laevigata Wall.) induced by summer pruning

The growing recognition of mulberries as a potent source of bioactive and nutritional compounds, coupled with their increasing global consumption, underscores the need for efficient off-season cultivation. This study explores the influence of both in-season and off-season cultivation on the yield, bioactive components, and antioxidant activity of ‘Taiwan Changguosang’ (Morus laevigata Wall.) in a greenhouse setting. Despite the lower fruit yield during the off-season, the off-season fruit exhibits higher levels of bioactive compounds, including total anthocyanins, polyphenols, and flavonoids compared to its in-season counterpart. Additionally, the off-season fruit demonstrates enhanced DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging and FRAP (ferric-reducing antioxidant power), attributed to climatic conditions during fruit development, particularly air temperature and solar radiation. Moreover, the off-season fruit proves to be more palatable, showcasing a favorable balance between sugar and acid. Principal Component Analysis (PCA) and correlation analysis revealed a close association between antioxidant activity and the chemical contents of total polyphenols and flavonoids. This study underscores the feasibility and benefits of off-season cultivation for enhancing the nutritional profile and antioxidant potential of mulberries, providing valuable insights for optimizing cultivation practices.

Synergistic effect of net-houses and light sources on the enhancement of off-season flowering waves and production of ‘Da Hong’ red-fleshed pitaya

To meet the increasing demand for year-round production of ‘Da Hong’ red-fleshed pitaya (Hylocereus polyrhizus), which is limited by its natural flowering season in the summer and has been a dominant cultivar in Taiwan, China and East-SouthEast Asia owing to its self-compatibility and excellent fruit quality, extending the off-season cultivation period has become a crucial endeavor. This study aimed to assess the effects of net-houses and light sources on off-season (spring and winter) fruit quality yield of ‘Da Hong’ red-fleshed pitaya in Taiwan. Mature six-year-old plants were cultivated either in net-houses or open fields (OFs), with night-breaking achieved using artificial lighting: either 100 W incandescent bulbs (IBs) or 23 W compact fluorescent energy-saving bulbs (CFBs). The study was conducted during spring and winter in 2017–2018, with flowering rate and fruit production evaluated. Floral bud emergence in the net-house+IB and net-house+CFB groups preceded that in other treatments by at least 2 weeks during spring, with net-house+IB exhibiting the highest frequency of flowering waves (four in spring and three in winter). Across all treatments, night-breaking via artificial lighting in spring markedly increased yield, with IBs and CFBs producing similar outcomes. Quality-wise, OF cultivation surpassed net-house cultivation in spring, whereas net-house cultivation, particularly with IBs, proved more effective during winter. In summary, net-house cultivation offers several advantages for off-season production, including earlier peak flowering in spring, increased flowering cycles in both spring and winter, and higher flowering rates during winter. Overall, these results may help enhance and stabilize off-season ‘Da Hong’ red-fleshed pitaya cultivation. Moreover, the significance of our study has the potential to revolutionize the flowering physiology, the strategy to enhance year-round production and the advancement of agricultural sustainability in pitaya.

How to Improve the Production and Quality of Chirimoya (Annona cherimola Mill.) in the Tropical Andes

The production of chirimoya (Annona cherimola Mill) is seasonal; therefore, the fruit's prices and availability are compromised. This research aimed to develop technologies to improve the production and competitiveness of off-season chirimoya fruit production. This research was conducted in the subtropical valley of Tumbaco, Pichincha province, Ecuador. Chemical defoliants (zinc sulfate, hydrogenated cyanamide, and copper chelate) and a sprouting inducer (hydrogenated cyanamide) were evaluated to standardize and increase defoliation improve sprouting, and consequently bring the harvest season forward. The study was conducted on eight-year-old trees of San José de Minas and MAG-Tumbaco genotypes. The assessed variables were defoliation, sprouting, elapsed flowering time, and harvest period. The fruit harvest was shortened by 18.4 days by applying the defoliants and sprout inducer. For the San José de Minas genotype, the best response for defoliation (99%) was copper chelate at 1%, compared to the control with 58.9% defoliation at 35 days after its application. In the MAG-Tumbaco genotype, the best defoliation results were also obtained with cooper chelate at 1% (99.7% defoliation), while the control achieved 95.5% for 35 days after its application. In the latter genotype, defoliants significantly outperformed the control in terms of sprouting at 21 and 28 days after application; as a result, harvest was advanced by 22.6 days. These treatments should be tested in other climate zones to establish them as cultural practices to increase off-season fruit production, benefiting farmers and industry.

Analysis of the Incidence and Risk Factors of Precocious Puberty in Girls during the COVID-19 Pandemic.

Home quarantine due to the global coronavirus disease 2019 (COVID-19) pandemic has had a significant impact on children. Lifestyle changes have led to an increase in precocious puberty (PP) among girls, and the underlying risk factors for this remain unclear. Thus, we aimed to assess the influence of environmental, genetic, nutritional, and other lifestyle factors on the risk of PP in girls. We evaluated the incidence of new-onset PP in girls during home quarantine for COVID-19 and analyzed the potential risk factors. This was a retrospective questionnaire and medical record-based study involving 22 representative medical units from 13 cities in Henan Province, China. Girls with new-onset PP (central precocious puberty, 58; premature thelarche, 58; age, 5–9 years) between February 2020 and May 2020 were included, along with 124 healthy, age-matched controls. The number of new-onset PP cases reported during the study period was compared with that reported between February and May in 2018 and 2019. Patients' families completed a questionnaire to assess potential risk factors. There was a 5.01- and 3.14-fold increase in the number of new-onset PP cases from 2018 to 2020 and from 2019 to 2020, respectively; the differences were statistically significant (p < 0.01). High-risk factors for PP included longer time spent using electronic devices, decreased exercise time, higher body mass index, vitamin D deficiency, young age (<12 years) of mother during menarche, consumption of fried food and processed meat, residence in rural areas, and consumption of off-season fruits. Thus, we found that lifestyle changes caused due to the COVID-19 pandemic led to a significant increase in PP in girls. Management of the risk factors identified in this study may help in PP prevention.

Increasing off-season snake fruit (Salacca zalacca) yield by preventing fruit set failure with different exogenous auxin spray

Snake fruit blooms every three months, but only one to two of the flowering seasons result in fruit production. Failure of fruit set causes the fruit harvest seasonally. Therefore, the aim of this research was to increase off-season production by preventing the failure of fruit set with various exogenous auxin spray. The research was conducted in the snake fruit orchard at Bebandem Sub-District, Karangasem Regency, Bali Province, Indonesia, from February to November 2019. The experiment was designed as a nested factorial with a randomized block design. The treatment consisted of three types of auxin with a specific concentration for each, IAA at 0, 25, 50 and 75 ppm, IBA at 0, 50, 100 and 150 ppm, and NAA at 0, 50, 100 and 150 ppm. The IAA, IBA, and NAA were sprayed on the flowers and leaves 3 times in March, April, and May. The results showed the highest percentage of fruit set, fruit weight per tree, and weight per fruit obtained with IAA treatment were 59.80 %, 2,612.91 g, and 91.06 g, respectively. These results were not statistically different to those of the IBA and NAA. Furthermore, the IAA concentration of 25, 50, and 75 ppm produced a significantly higher percentage of fruit set compared with the control. The increased fruit set in the IAA, IBA and NAA treatments resulted in better yield than the control. The novelty of this result is that spraying snake fruit with IAA, IBA and NAA can prevent the failure of the fruit set. Therefore, IAA, IBA, and NAA are recommended to be applied to increase off-season fruit production of snake fruit.

Pembuahan Jeruk Siam (Citrus microcarpa L.) di Luar Musim dengan Perlakuan Induksi Pembungaan dan Zat Pemecah Dormansi

Fertilization outside the season of Siam Orange (Citrus microcarpa L.) with Induction of Flowering and Dormancy Breaking Substances. The Siam orange (Citrus microcarpa L.) produces seasonal fruit with the on-season harvest from July to August while the off-season harvest, i.e. from February to September there is hardly any fruit, or very limited supply. The purpose of this study was to examine the response of flowering induction and dormancy-breaking substances to produce off-season fruits of Siam orange. This research began in April to December 2016. The experiment was arranged factorially with two factors using a randomized block design (RBD), with nine combination treatments and six replications. Flowering induction factors consist of three levels, namely Ik = Control, IP = Paclobutrazol at a dose of 7.5 g/l, and Im = cutting the tip of dormant twigs. Dormancy-breaking substances factor consists of three levels, namely Dk = Control, Db = BAP 200 ppm, and Dn = KNO3 300 ppm. The results of the experiment showed that the highest fruit weight per tree at off-season production was obtained by induction with paklobutrazol (28.86 kg) and the lowest was in control (12.75 kg). Flowering induction treatments was not significantly different effect on fruit quality of Siam orange, represented by weight per fruits, fruit diemater, total soluble solid and vitamine C content was not siginificant different among levels of treatment. Dormancy-breaking substances treatment also not significantly effect on fruit quality of Siam orange. Based on this research it is recommended to induce flower for off-season produce of Siam orange by pruning the tips of dormant twigs or by using paklobutrzol.

The Influence of Product Quality on Export Performance: Eco-Efficient Value in South African Peach and Nectarine Fresh Exports

This study evaluates the role of quality in influencing export earnings. It argues that different types of product attributes confer different quality features and these features provide diverse consumer value which influence the export product’s market performance. The gravity model is used to regress export earnings against indices measuring product value propositions, as well as economic, demographic, demand and trade regulation indicators. It uses data from South Africa’s fresh peach and nectarine exports and 21 trading partners for the period between 2001 and 2017. The study’s results show that improvements in the delivery of esthetic quality were associated with increases in export earnings. On the other hand, improvements in eco-efficiency (sustainable production and consumption) and the delivery off-season fruit were associated with lower export earnings. The results reiterate the importance of providing consumer value, the provision of communication for any additional environmental quality-upgrades and consensus in quality definitions with importing countries.

Effect of Processing Steps on Bioactive Compounds and Antioxidant Activities of High Anthocyanin Mulberry Fruit Powder

The objective of this research was to determine the amounts of bioactive compounds and antioxidant activities in each processing step in the production of high anthocyanin powder (HAP) from mulberry fruits to investigate suitable processing methods. For fresh mulberry fruits derived of Chiang Mai varieties, both in-season and off-season fruits had similar amounts of total anthocyanin content (TAC) and total phenolic compounds (TPC). In-season mulberry fruits had the highest potential to be used as a raw material for further study because of high antioxidant activities, large fruit size, and high productivity. Two methods of HAP production were tested. The first method used whole fruit drying with different drying methods included hot air drying (HAD), vacuum drying (VD), and freeze drying (FD). Hot air drying at 50, 60 and 70°C showed a decreased concentration of anthocyanins, which were 60% lower than that of fresh fruits. Vacuum drying at 55 and 75°C could provide high anthocyanin content and was similar to freeze drying, which had 87–97% anthocyanin retention. Vacuum drying at 75°C was most suitable for HAP production because of the short drying time (22.3 ± 0.4 hours), high anthocyanin retention (87.21%), high phenolic compound content, and high antioxidant activities. The second method used fermented and concentrated mulberry juice. This process used the following steps: yeast fermentation to decrease the sugar content, filtration to get rid of solid parts, evaporation to concentrate the solution, drying with different drying methods (vacuum drying and freeze drying), and crushing to powder. Throughout fermentation, filtration, and evaporation, high phenolic compound content and antioxidant activities were observed and 77.29% of anthocyanins were retained. However, these values decreased dramatically after the drying step. Therefore, drying the concentrated solution was not effective for HAP production. Of the processing methods tested, directly drying whole mulberry fruits with VD at 75°C was most suitable for HAP production. This method provided 13.06% ± 0.35 production yield of HAP, contained 13.51±0.08 mg/g DW of total anthocyanins, and 27.47 ± 0.50 mg GAE/g DW of total phenolic compounds. Additionally, the antioxidant activities by DPPH, TRAP, and TEAC assays were 2.91 ± 0.19, 16.22 ± 0.31, and 22.34 ± 0.29 mmol GAE/g DW, respectively.

Effort to increase off-season production and fruit quality of Siam orange (Citrus nobilis var. microcarva L.) through application of mycorrhizal inoculants and auxin

The study was conducted in Belancan Village, Kintamani, Bangli, Bali, from February to October 2018 with the aim to study the effect of application of mycorrhizal inoculants and auxin to increase off-season production and fruit quality of Siam orange. This experiment used a randomized block design with 2 factors. The first factor mycorrhizal inoculant dosages (0, 50, and 100 g/tree), while the second factor auxin concentrations (0, 50, 100 and 150 ppm/tree), and repeated 3 times. The results showed that the interaction of mycorrhizal inoculant dose and auxin concentration did not significantly effect to all of observed variables. The dose of mycorrhizal inoculant 100 g/tree increased off-season fruit production and quality of fruits, which was reflected by increase number of fruits per tree (142.17 fruits), weight per fruit (96.00 g), weight of fruit per tree (13.53 kg), and total dissolved solids (14.10 %Brix), or an increase of 44.21%; 11.89%; 57.87% and 21.03% compared to without mycorrhizal inoculant (108.58 pieces; 88.80 g; 10.57 kg and 11.65 %brix). Concentration of auxin 100 ppm/tree increased off-season production and quality of fruits, reflected by the higher number of fruits/trees (155.22 fruits), fruit weight per tree (15.03 kg), weight per fruit (96.50 g) and total dissolved solids (14.43% brix), compared to without auxin i.e. 112.11 pieces; 10.44 kg; 84.66 g; and 11.15% brix. The significant result of this research was mycorrhizal inoculant dose of 100 g/tree and auxin in the form of IBA 100 ppm/tree proven fruit drop, increased off-season fruit production and quality of fruits of Siam orange.

Influence of de-blossoming treatments on physico-chemical characteristics of selected mango varieties during off-season fruit production under South Gujarat conditions

A trial was undertaken under South Gujarat conditions to assess the effect of de-blossoming in six mango varieties during regular flowering season on off season fruiting characters. The investigation consisted of four de-blossoming treatments i.e. foliar sprays of NAA @ 400 and 800 ppm, hand-deblossoming and untreated trees which were imposed on six mango varieties i.e. Amrapali, Baramasi, Neelphanso, Neelum, Ratna and Totapuri during 2013-14 and 2014-15. De-blossoming was done at full bloom stage for induction of off season flowering. Results revealed that in the regular season cv. ‘Neelphonso’ recorded significantly the highest Total Soluble Solids while, minimum titrable acidity was recorded by Totapuri. Whereas, reducing sugar was significantly the highest in ‘Amrapali’ and ascorbic acid content was significantly the highest in ‘Neelum’ variety. With regard to off-season fruiting, significantly maximum Total Soluble Solids and minimum acidity was recorded in cultivar ‘Neelphonso’. The maximum reducing sugar was observed in ‘Ratna’ cultivar. Ascorbic acid was significantly the highest in ‘Neelum’ during first year and in ‘Ratna’ during the second year. Hand de-blossoming was found superior over control for Total Soluble Solids content in the varieties selected for this study under South Gujarat conditions. De-blossoming did not exert a significant influence on acidity, reducing sugar and ascorbic acid of the fruits.

Respon Pemupukan Terhadap Hasil dan Kualitas Hasil Salak Gula Pasir (Salacca zalacca cv. Gula Pasir) di Luar Musim Serta Kandungan Air Dan Klorofil Daun

Fertilization Response to Off-Season Production and Fruit Quality of Salak Gula Pasir (Salacca Zalacca cv. Gula Pasir) and water and Chlorophyll Content of Leaves. Naturally salak Gula Pasir (Salacca zalacca cv. Gula Pasir) flowers every three months a year, but only one to two seasons of the flowers can develop into fruit. Failure of flowers develop into fruit, usually call fruit-set failure, causes the fruits be available seasonally in a short time period, only 2-3 months a year, i.e. during the harvest time (on-season period) from December to February. This research aimed to know response of fertilization to off-season production and fruits quality of salak Gula Pasir and its ralatinship to water and chlorophyll content of leaves. The study used a randomized block design with the treatment was fertilization, consists of 14 levels (fertilized according farmers’ way with leaf midrib only/control, fertilized with compost, mycorrhizal biofertilizer, inorganic NPK, combination of farmers' way and compost, combination of farmers’ way and mycorrhizal biofertilizer, combination of farmers' way and inorganic NPK, combination of compost and mycorrhizal biofertilizer, combination of compost and inorganic NPK, combination of mycorrhizal and inorganic NPK, combination of farmers’ way, compost, and mycorrhizal biofertilizer, combination of farmers’ way, compost, inorganic NPK, combination of farmers’ way, mycorrhizal biofertilizer and inorganic NPK, and combination of farmers’ way, compost, mycorrhizal biofertilizer, and inorganic NPK). Each treatment was repeated 3 times. The study was carried out in the off season period from April to Nopember 2018 at the production center of salak Gula Pasir plantation i.e. at Sibetan Village, Bebandem District, Karangasem Regency. The results showed that the highest fruit weight per tree at the off-season was obtained on combination of fertilization of farmers' way and mycorrhizal biofertilizer (of 2536.67 g) and the lowest was on control/fertilized according farmers’ way (1,220.00 g). Fertilization with compost, mycorrhizal biofertilizer, and inorganic NPK singly, or by combining it, increases the quality of off-season fruit of salak Gula Pasir, reflected by the increase of weight per fruit, fruit diameter and fruit sweetness compared to control. The lower of yield per tree and quality of fruit on control compared to other fertilization treatments was relate to low relative water content and chlorophyll content of leaves.

Quality aspects of fresh‐cut ‘long‐storage tomato’ as affected by package, calcium chloride and storage time

SummaryIn this research, some quality changes during storage at 4 °C were assessed in fresh‐cut fruits of a ‘long‐storage tomato’ landrace, packaged in biocompostable materials (PLA Ingeo tray/NatureFlex™ film) or in conventional plastics (PET tray + polypropylene film). The effects of dipping in CaCl2 on the shelf‐life extension were also assessed. Plants were cultivated both off‐season (greenhouse) and in‐season (open field). CO2 and O2 concentration, fruit weight loss, firmness, colour, microbial load were measured at 0, 4, 7, 12 days of storage. Headspace gas changes and fruit weight loss were minimised in conventional package. BIO package prevented water condensation, led to max 5% weight loss and made fruits less susceptible to spoilage. Dipping in CaCl2 induced better firmness, especially in biopackage. Off‐season fruits had overall lower quality than in‐season fruits; however, these may contribute to extend the production season, with interesting marketing implications for the agri‐food industry.

POSTHARVEST OF IRRADIATED TAHITI LIME FRUITS

ABSTRACT This study aimed to evaluate the postharvest quality evolution of gamma-irradiated ‘Tahiti’ limes. Shiny, olivegreen fruits with coarse skin (56 cm equatorial diameter) harvested in commercial orchars and processed in commercial packing house line were used. In a preliminary assay, fruits harvested in April 2011 were exposed to a gamma radiation range from 0 to 750 Gy. The 250 and 750 Gy doses negatively affected skin quality and pulp of exposed fruits. For this reason, new assays were carried out using lower doses to irradiate fruits harvested in July 2011 (off-season) and January 2012 (regular harvest period). Fruit harvested in both periods were selected and exposed to radiation doses of 0, 50, 100, 150, and 200 Gy. All irradiations occurred at a rate of 0.46 Gy/h. After fruit irradiation, physical and chemical analyses were performed along a 20-day storage period at room temperature (24 ± 1ºC and 80 ± 5% RH). Irradiation of fruits harvested in July 2011 and January 2012 and treated with doses of up to 200 Gy did not affect the ascorbic acid content, but doses &gt; 100 Gy caused skin yellowing of fruits harvested on both periods. Gamma radiation at doses = 50 Gy reduced the total soluble solids content in off-season fruits. Exposure of fruits harvested in the main harvest period to radiation doses = 150 Gy increased weight loss. Irradiation of ‘Tahiti’ limes at doses between 50 Gy and 700 Gy did not preserve postharvest quality during storage at room temperature.

Combating climate change through off-seasonally raising seedling of papaya (Carica papayaL.) in protected environment

Major difficulty of raising papaya seedling is mortality of seedling, among abiotic factors of environment like unfavourable microclimate; especially temperature restricts raising off-season fruit nursery under open field condition in arid region. Papaya (Carica papaya L.) is widely grown fruit crop in tropics and India is the largest producer in the world. Papaya seedlings are fetching very high price during off-season availability. In this study, a low tunnel greenhouse (S1) and black shade net house (S2) were taken as protected structures for growing of papaya seedlings. The variety of papaya seedlings was Madhubindu and soil+FYM was taken as growing media for this study. Survival and growth of seedlings were monitored for 30–60 days. The environmental and morphological data were recorded and computed and response of papaya seedling growth was evaluated in terms of germination percentage, seedling height, collar diameter, number of leaves, diameter of shoot, fresh and dry weight of aboveground and underground biomass, sturdiness, root: shoot ratio, vigour index length andvigour index mass in root media. The results of this study revealed that the environmental factor during the entire study period was found significant in black shade net structure compared to greenhouse. Variation in seedling growth in different microclimatic conditions may be due to the differences in growth behaviour under given set of environmental conditions. The minimum time taken for days of germination, germination percentage, seedling height, collar and shoot diameter was found highest in black shade net house (S2) with variety i. e. Madhubindu and soil+FYM as growing media. Economically black shade net house with net profit 513.27 Rs./m2, BCR 3.94 and payback period 0.59 was found highly suitable for raising seedling of papaya off-seasonally and mitigating climate change in arid region.

PHENOLOGY OF JACKFRUIT (ARTOCARPUS HETEROPHYLLUS LAM.) AND EFFECTS OF PACLOBUTRAZOL ON OFF-SEASON FRUIT PRODUCTION

The production of female inflorescence of jackfruit ‘EVIARC Sweet’ was not continuous and occurred between January to June and November to December. However, leaf and shoot production was continuous throughout the year. Fruit harvesting started in April up to December. The application of paclobutrazol at 1 g a.i. m-1 of canopy diameter increased female inflorescence production without negative effect on fruit set. Female inflorescences were produced in the months of August and September; this was not observed in untreated trees. As a result, off-season fruits were produced.

Effect of Ethrel on the Starch Sugar Changes of Off-Season Fruits of Mango (M&lt;i&gt;angifera indica&lt;/i&gt; l. Var. Neelum) during Ripening

The present investigation is aimed at studying the effect of ethrel on the ripening of off-season fruits of Mangifera indica L. var. Neelum. The control fruits were kept in the laboratory naturally while the experimental fruits were treated with different concentrations of ethrel (100, 200 and 300 ppm). In control fruits, partial ripening led to incomplete metabolic changes, which did not alter the presence of sourness in the fruits. Hence, they were not fit to be eaten. On the other hand, the fruits treated with different concentrations (100, 200 and 300 ppm) of ethrel ripened on 13th day, 11th day and 9th day respectively after treatment. The colour changed from green greenish to yellow and the fruits were palatable in nature. The starch decreased during ripening, both in the treated and control fruits. On the other hand, the sugar, α-amylase, β-amylase, activities increased. Among the different 100, 200 and 300 ppm ethrel treatments, the 200 ppm alone had the optimum effect on the ripening of off-season fruits of Mangifera indica L. var. Neelum.

Effect of Ethrel on the Starch Sugar Changes of Off-Season Fruits of Mango (M&lt;i&gt;angifera indica&lt;/i&gt; l. Var. Neelum) during Ripening

The present investigation is aimed at studying the effect of ethrel on the ripening of off-season fruits of Mangifera indica L. var. Neelum. The control fruits were kept in the laboratory naturally while the experimental fruits were treated with different concentrations of ethrel (100, 200 and 300 ppm). In control fruits, partial ripening led to incomplete metabolic changes, which did not alter the presence of sourness in the fruits. Hence, they were not fit to be eaten. On the other hand, the fruits treated with different concentrations (100, 200 and 300 ppm) of ethrel ripened on 13th day, 11th day and 9th day respectively after treatment. The colour changed from green greenish to yellow and the fruits were palatable in nature. The starch decreased during ripening, both in the treated and control fruits. On the other hand, the sugar, α-amylase, β-amylase, activities increased. Among the different 100, 200 and 300 ppm ethrel treatments, the 200 ppm alone had the optimum effect on the ripening of off-season fruits of Mangifera indica L. var. Neelum.

PROTECTED CULTIVATION OF PLUM IN SOUTH CENTRAL LIAONING: PRESENT STATUS AND FUTURE PERSPECTIVES

Inspired by the protected vegetable production methods in south central Liaoning, which was the cradle of Chinese greenhouse vegetable production in, protected fruit production began to flourish approximately twenty years ago. Protected fruit culture first occurred in Liaoning and then it extended to north central China, mainly to advance the time of ripening to meet the demand of off-season fruit consumption. The main fruits that were grown were the perishable fruit types such as stone fruits and berry fruits, including peach, cherry, apricot, plum and table grape. Table grape and peach were relatively easy to cultivate in protected conditions since the growth of grapevines or peach trees is easy to control and fruit set readily occurs, while plum, apricot and cherry tree are more difficult to work with. The purpose of this paper is to describe the growing technology of the protected plum cultivation system including the greenhouse structure, cultivar selection, the methods of forcing dormancy, heating the greenhouse etc. The present status and future perspectives of this system are also discussed.

Effect of mulching systems on fruit quality and phytochemical composition of newly developed strawberry lines

The effects of three mulching systems on total yield, average yield per plant, average fruit weight, soluble solids content (SSC), titratable acidity (TA), firmness and oxygen radical absorbance capacity (ORAC) of two newly developed lines (‘Orléans’ and ‘Saint Pierre’), one advanced selection (‘SJ8976-1’) and two commonly used cultivars (‘Jewel’ and ‘Kent’) were evaluated. The studied mulching systems were: plastic mulch (PM), mulch with row cover (PMRC), and matted-row system (MRS). Results showed that plastic mulch with row cover (PMRC) generally increased yield per plant, average fruit weight, SSC, firmness and ORAC, but differences varied within harvest times. No significant differences in total yield and TA were observed under the selected mulching systems. Both PMRC and PM accelerated the harvest periods compared to MRS. ‘Kent’ and ‘Jewel’ had the highest total yield while ‘SJ8976-1’ and ‘St-Pierre’ had the highest average fruit weight. The highest SSC, TA and ORAC were found in ‘Jewel’. There was no interaction between the mulching systems and genotypes, indicating that the effect of production system is independent of cultivars. PMRC seems to be a better growing system, improving fruit quality and increasing the nutritional value of all genotypes. By allowing off-season fruit production in cool climates, PMRC can be an alternative method to the costly high tunnels.

Modeling, Characterization and Analysis of the dynamic behavior of heat transfers through polyethylene and glass walls of Greenhouses

The conventional agricultural tunnel greenhouse is highly widespread in Mediterranean countries, despite the shortcomings it presents, specifically the overheating during the day and the intense cooling at night. This can sometimes lead to an internal thermal inversion. The chapel-shaped glass greenhouse is relatively more efficient, but its evolution remains slow because of its investment cost and amortization. The objectives of the agricultural greenhouse are to create a microclimate that is favorable to the requirements and growth of plants from the surrounding climatic conditions and produce cheap off-season fruits, vegetables and flowers which must be highly available all along the year. The agricultural greenhouse is defined by its structural and functional architecture as well as by the optical, thermal and mechanical qualities of its wall and the accompanying technical support.The greenhouse is supposed to be a confined environment where there is an exchange of several components. The main intervening factors are: light, temperature and relative humidity.When protected, the culture heats up more than when in free air because of the wall that acts as a barrier to harmful influences of the wind and the surrounding climatic variations as well as to the reduction in internal air convection.This thermal evolution state depends on the air-tightness degree of the cover and its physical characteristics. It has to be transparent to solar rays, and must as well absorb and reflect infrared rays emitted by the soil. This leads to trapped solar rays, called the “greenhouse effect”. In this article, we propose the dynamic modeling of the greenhouse system, the characterization and analysis of the thermal behavior of the wall for both experimental greenhouses, where the first one is made of polyethylene (tunnel greenhouse) and the second of glass (chapel-shaped greenhouse), throughout experimentation and simulation which finally lead to identifying the evolution in the thermal loss coefficient (K) through the wall.