Keitt Mango Research Articles

Surfactant-enhanced chitosan coating extends postharvest shelf-life of Keitt mango

The surface properties of Keitt mango and wettability of chitosan (CH) coatings containing ethyl lauroyl arginate (LAE, an ionic surfactant), and sucrose monolaurate (SML, a non-ionic surfactant) were investigated. The Keitt mangoes were coated with different chitosan-based solutions and stored at room temperature (25.0 ± 0.6 °C) for 35 days. The Keitt mango surface had low surface energy (<100 mN/m) with high dispersive component (17.70 ± 1.49–22.86 ± 1.02 mN/m). SML and LAE surfactants significantly (P < 0.05) lowered the surface tension of the CH coating solution by 6.94, and 24.13 mN/m, respectively. As a result, the wettability of CH based coating on mangoes was improved to −68.37 ± 0.01 mN/m (CH-SML), and −30.29 ± 0.00 mN/m (CH-LAE) compared with CH (−76.45 ± 0.04 mN/m), resulting in smooth and homogeneous coatings. The storage test results indicated a significant reduction (P < 0.05) in disease incidence and weight loss by the CH-SML and CH-LAE coatings and the coated mangoes were firmer with lower pH values compared with the control. This study suggests that CH-LAE and CH-SML coatings can effectively extend the shelf-life of Keitt mangoes by 10 and > 15 days, respectively.

Storing Keitt Mangoes Using Eco-Friendly Treatments

Storing Keitt Mangoes Using Eco-Friendly Treatments

Introducing in Côte D’ivoire a Simple Technique Contributing to the Post-Harvest Management of Mangoes (Mangifera indica L. 1753) Perishability and Browning by Targeting Polyphenol Oxidases (PPOs)

Côte d'Ivoire is the leading exporter of Palmer and Keitt mangoes in sub-Saharan Africa. Despite the importance of the foreign exchange generated, these tropical fruits suffer enormous post-harvest losses due to their high perishability, mainly caused by enzymatic browning. In fact, the appearance of brown discolouration due to alterations, whether caused by mechanical, technological or natural treatment, is the cause of huge economic losses. To address this thorny problem and thereby improve export volumes, three technological treatments including steam bleaching, oven drying and osmotic dehydration were carried out on mango edible parts to inhibit polyphenol oxidases (PPOs), the key enzymes that catalyse enzymatic browning. The results showed that only oven drying at 60°C and steam bleaching at 60°C and 100°C had a significant effect on inactivating PPOs activity after only a few minutes. Osmotic dehydration maintained high levels of enzyme activity even after 24 hours of treatment. In conclusion, steam bleaching at 60°C for 7 minutes was found to be the best post-harvest management technique for Palmer and Keitt mangoes, as it contributed to both the preservation of marketable quality and the stability of organoleptic properties of the mango.

Determination of Levels of Selected Essential and Non Essential Metals in Mango (Mangifera indica L.) Cultivated in Wolaita Zone, Southern Ethiopia

Background: Mango (Mangifera indica L.) is one of the most important tropical fruits commercialized and consumed worldwide fresh or processed, having an attractive color and distinct taste and aroma. The main objective of this study is to determine the level of selected essential and non-essential metals in Mango. Methods: The levels of essential and non-essential metals were determined in mango (Mangifera indica L.) samples collected from four different sites (Boloso Bombe, Boloso Sore, Damot woyde and Humbo) in Wolaita Zone, Southern Ethiopia by flame atomic absorption spectrometry. A 0.5 g dried powdered mango sample was digested with 1 mL of nitric acid (HNO3), 3 mL of perchloric acid (HClO4) and 1 mL of hydrogen peroxide (H2O2) at 180°C for 2:00 hours. The study focused on two mango varieties, the Apple mango and the Keitt mango. Result: The metal contents in the apple mango in mg/kg were found in the following order: Mg (20.04-0.34) greater than Ca (1.49-6.78) greater than Zn (2.32-4.23) greater than Fe (2.77-2.85) greater than K (2.03-2.41) greater than Na (1.72-1.97) greater than Mn (0.47-1.36) mg/kg; and that of the Keitt mango samples in mg/kg were in the order of: Mg (2o.08_20.34) greater than Ca (0.95_5.84) greater than Zn (2.69_3.66) greater than Fe (2.69_2.90) greater than K (1.91_2.77) greater than Na (1.79_1.93) greater than Mn (0.38_0.72) mg/kg, respectively. The levels of Cd and Pb were below method detection limit. Analysis of variance (ANOVA) at 95% confidence level indicated that there is significant difference in the mean concentration of all metals between the four sample sites. There was good correlation between the levels of some metals (Mg, Ca, Zn, Fe K, Na and Mn) in both varieties of mango samples. From the results of this study it can be concluded that the studied mango varieties grown in the study area are good source of essential metals and free from the toxic metals: Cd and Pb.

Assessing the Role of Gaseous Chlorine Dioxide in Modulating the Postharvest Ripening of Keitt Mangoes through the Induction of Ethylene Biosynthesis.

Consumer acceptance of Keitt mangoes (Mangifera indica L.) is significantly affected by their slow postharvest ripening. This work used gaseous chlorine dioxide (ClO2(g)) to prepare the ready-to-eat Keitt mango and explored the potential mechanisms for the mango ripening. Harvested mangoes were treated with 20 mg·L-1 of ClO2(g) or ethephon for 3 h (25 °C) and left in a climatic chamber with a temperature of 25 ± 1 °C and a relative humidity of 85 ± 5% for 4 d. The results showed that ClO2(g) treatment significantly promoted the orange coloration of mango flesh compared to the untreated control group. Moreover, ClO2(g) treatment significantly elevated the total soluble solids, total soluble sugar, and total carotenoids content of mangoes, whereas the firmness and titratable acidity were reduced. ClO2(g)-treated mangoes reached the edible window on day 2, as did mangoes treated with ethephon at the same concentration, except that the sweetness was prominent. The residual ClO2 level of the mangoes was <0.3 mg/kg during the whole storage time, which is a safe level for fruit. In addition, ClO2(g) significantly advanced the onset of ethylene peaks by 0.5 days and increased its production between days 0.5 and 2 compared to the control group. Consistently, the genes involved in ethylene biosynthesis including miACS6, miACO1, and miACO were upregulated. In sum, ClO2(g) can be a potential technique to reduce the time for harvested mango to reach the edible window, and it functions in modulating postharvest ripening by inducing ethylene biosynthesis.

Biostimulants Improve Yield and Quality in Preharvest without Impinging on the Postharvest Quality of Hass Avocado and Mango Fruit: Evaluation under Organic and Traditional Systems

The fruit agribusiness sector is one of the most dynamic in Colombia. Within this sector, avocado and mango are of great importance, both in terms of area planted and volume exported. Increasing the productivity, quality, and postharvest life of these fruits is a priority, due to the high losses that occur in the preharvest and postharvest stages. One current alternative to achieve this are biostimulants, which have the potential to improve the productivity and quality of fruit. The objective of this work was to evaluate the effect of the preharvest application of two biostimulants on the yield and quality of avocados and mangos. The study was carried out in production systems for cv. Hass avocado (traditional and organic) and cv. Keitt mango (traditional). In each system, two treatments were evaluated: conventional and conventional + biostimulant. Under field conditions, yield and quality variables such as weight, number of fruits, visual appearance, and size were determined. In postharvest, the fruits obtained from preharvest treatments were subjected to two storage conditions (6 and 20 °C) during the ripening process. Postharvest quality variables such as respiration, ethylene rates, weight loss, color index, firmness, total soluble solids, and titratable acidity were evaluated. The results indicated that the use of biostimulants caused a significant increase (p ≤ 0.05) in the yield, number of fruits, and preharvest quality parameters of size and weight, without negatively affecting the postharvest quality of the fruits. The biostimulant increases the total weight of fruits in organic and conventional avocado by ~55 and 25%, respectively, while in mango, this figure increased by ~23%. Hence, biostimulants can be utilized to increase the productivity of fruit trees.

Economic Assessment of Coloured Shade Net Improve Growth and Yield in Mango CV. Keitt

Coloured shade net is an effective tool for sustainable agricultural production. Shade nets of five colours (white, yellow, red, blue and black) in comparison to an open field conditions which were studied in a Keitt mango. The aim of the study was to explore the profitability of different coloured shade net (white, yellow, red, blue, black and control) on the Keitt mango yield during the period of 2016- 2020.&#x0D; The results showed that white coloured shade net was better to increase the yield per 2000 m2. The average yield of the trees under white coloured shade net was about 7.3 kg/tree compared to about 6.3, 5.8, 5.1, 4.3, 4.3 kg/tree for "yellow, red, blue and black" coloured shade net and control respectively. The black coloured shade net had the lowest economical profit. Thus, growing mango under white coloured shade net is helpful to increase marketable, exportable yield and quality of mangoes compared to other treatments.&#x0D; Keitt mango, ratio of revenues to costs, unit costs of production, coloured shade net.

ECONOMICAL EVALUATION OF MANGO (CV. KEITT) TREES UNDER COLOURED SHADE NETS

This study explored the economical viability of five different coloured shade nets (White, yellow, red, blue and black) on mango production (Mangifera indica L. cv. Keitt). This study investigated the climatic parameters in terms of light intensity, minimum and maximum air temperature, relative humidity and plant growth across 2019 and 2020 seasons. When compared to open field conditions, coloured shade nets resulted in higher maximum temperatures and relative humidity. The black net cover and open field treatments gave the lowest mango yield compared to all greenhouse net cover. When compared to the other treatments, the use of white or yellow nets resulted in a considerable increase in the number of fruits and total yield per plant. According to prevailed conditions, it could be concluded that optimum microclimate for growing mango in similar conditions could be obtained under white and yellow nets compared to the other net covers. Black greenhouse net cover gave the lowest productivity during the experimental duration. Production costs, total revenue, net return and ratio of total revenue to cost for Keitt mango in Egypt are presented in this study. The result shows that the net return for white net reached 15777 Egyptian pound (LE) and LE 15270 per m2 in 2019 and 2020 respectively, which was 2.63 times those grown in the open field (LE 5980 and LE 5081 per 2000 m2) in 2019 and 2020 respectively. However, Revenue to cost ratio was found higher in white net in both seasons which were 1.9 and 1.8 respectively.

Sensory, Micrographic and Physico-chemical Characterization of Kernel Almond Flour of Two Varieties of Mangoes Grown in Northern Côte d'Ivoire

Fruit of mango tree (Mangifera indica L.) is most traded worldwide among Anacardiaceae. Kernels from mango processing units in northern Côte d'Ivoire are waste to be recovered to avoid environmental pollution. This work therefore aims to study sensory, micrographic and physico-chemical characteristics of almond flours from kernels of Kent and Keitt mangoes varieties. Kent mango stones were collected at drying factory Gninnangnon of Korhogo (Côte d'Ivoire). As for kernels of Keitt, they come from mangoes from orchards of Korhogo. These kernels were washed, dried at 50°C for 72 hours before extracting almonds which were reduced to flour by grinding. Sensory analysis showed that Kent (FKent) and Keitt (FKeitt) flours were belgian, lightly scented and flavored, bland in taste, soft to touch and slightly astringent. Micrographic analysis of flours FKent and FKeitt revealed cracked starches contained in cells of parenchyma, cracked starches isolated from parenchyma, fiber fragment, paracytic stomata, protective long twisted unicellular and fragment of endocarp. Concerning physicochemical parameters, results showed that moisture of flours FKent and FKeitt were respectively 7.77±0.38% and 7.44±0.19% with ash contents of 2.50±0.01% and 2.25±0.01%. Their lipids contents of flours FKent and FKeitt were respectively 18.74±0.24% and 21.54±0.31% while those of proteins revealed 10.54±0.05% and 8.31±0.02%. Flours FKent and FKeitt contained respectively 60.43±0.64% and 60.48±0.48% of carbonates. Finally, fatty acid profile of flours FKent and FKeitt revealed linoleic, oleic, stearic and palmitic acids. This study showed that flours FKent and FKeitt could be used in cosmetics and animal feeding.

Kaolin Improves Photosynthetic Pigments, and Antioxidant Content, and Decreases Sunburn of Mangoes: Field Study

The Keitt mango tree has a low canopy that leads to an increase in sunburned fruits. Hence, the fruit quality is markedly reduced due to the fruit being exposed to physiological disorders. The sunburn injury problem is common due to high levels of solar radiation and the low number of leaves, which minimizes the protection of small, newly formed fruits. Kaolin spray has emerged as a promising approach for mango trees since it improves vegetative growth, yield, and fruit quality in new lands. This search aimed to study the influence of spraying kaolin on Keitt mango trees grafted on ‘Succary’ rootstock. The treatments were as follows: control, 2%, 4%, and 6% of kaolin. Our results indicated that the applications of kaolin significantly improved leaf area, tree canopy volume, photosynthesis pigments such as chlorophyll-a and b, carotenoids of leaf and yield (kg/tree), and the physical and chemical characteristics of Keitt mango cultivar in comparison with the control. A higher concentration of kaolin decreased the leaf content of antioxidants such as total phenolic, total flavonoid, CAT, POX, and PPO enzyme activities. Furthermore, the number of sunburned fruits was significantly reduced after the application of kaolin in comparison to control fruits. Regarding vegetative growth, our results indicated that adding kaolin at 6% enhanced the leaf surface area and tree canopy volume compared to the control and other treatments. A similar trend was noticed regarding yield and fruit quality, whereas the best values were obtained when kaolin was sprayed at a concentration of 6%. In conclusion, the application of kaolin can improve the production and fruit quality of Keitt mango trees by reducing the effects of adverse summer conditions.

Impact of Shading and Foliar Spray with Some Nutritive Solutions on Growth, Nutritional Status, Productivity and Fruit Quality of Keitt Mango Trees

Impact of Shading and Foliar Spray with Some Nutritive Solutions on Growth, Nutritional Status, Productivity and Fruit Quality of Keitt Mango Trees

Aroma of mature-green and tree-ripe mangoes after refrigerated air or controlled atmosphere storage

ABSTRACT: Mango flavor is dependent on cultivar characteristics and postharvest handling procedures. Mangoes harvested with the ripening metabolism initiated develop better flavor than mangoes harvested at the mature-green stage. Different cultivars were harvested at both ripeness stages and evaluated to determine the effect of fruit ripeness, storage temperature and atmosphere on the volatiles present in aroma profiles. Mangoes of the cultivars Haden, Keitt and Tommy Atkins at distinct ripeness stages were stored in controlled atmospheres (CA) with 2, 5 or 21 kPa O2 plus 0, 10 or 25 kPa CO2 at 5, 8, 12 or 15 °C. Terpene concentrations of mangoes stored in air were higher than the concentrations in mangoes stored in CA. The sesquiterpene α-copaene did not present recognizable peaks in almost all elusion sequences. The same result was observed with the monoterpene β-pinene in cv. Haden and cv. Keitt mangoes while in ‘Tommy Atkins’ fruit β-pinene concentrations were below 1.06 µL.L-1. Ethanol and acetaldehyde concentrations were significantly higher in mangoes from 2 kPa O2 storage than those from air storage or the other CA treatments. Terpene synthesis in air or CA storage in all cultivars varied significantly, preventing generalizations as to what storage conditions favor or limit aroma components elution.

Effect of Ripening Stages and Drying Method on the Physico-chemical and Sensory Properties of Keitt Mango (Mangiferaindica L.) Sliced Chips

Fruits (30-50%) harvested in developing countries does not reach consumer due to using inappropriate method of processing. The objective of this study was to investigate effect of ripening stage and drying methods on physicochemical and sensory properties of dried sliced mango chips. mango rich as sources of vitamins A, B and C and consumed for pleasant taste and flavor. This study was lied down with two factors on completely randomized design. Different drying methods (solar drying and oven drying) and ripening stage (unripe, intermediate and fully ripe) were evaluated for physicochemical quality. The effect of factors on properties determined by Analysis of variance and significance at (p &lt;0.05). The data was collected from oven dry and solar drying with three replication and analyzed by using SAS software. The solar dried mangoes were evaluated for changes in moisture content (8, 8.83 and 9.83), ash content (3, 2.33 and 2.5), pH (4.02, 5.02 and 6.11), TSS (2.45, 2.83 and 3) rehydration capacity (50.83%, 63.93% and 58.65%), ascorbic acid (3.24, 1.82 and 1.47) and titratable acidity (0.05, 0.02 and 0.02) with unripe, intermediate and fully ripe mango respectively. The result showed that, for solar drying methods the best ripening stage was fully ripen. Other parameters also best for physicochemical qualities of solar-dried samples than ovendried samples. Generally, present study showed that, solar dried samples was the highest in rehydration capacity at unripe, intermediate, and fully ripen and higher in other physicochemical properties at ripening stage (unripe, intermediate, and fully ripen) compare with oven dried. However, because of some constraints, some parameters were not included. Therefore, based on the limitation of the work, further research is needed to study the effect of Ripening Stages and Drying Method on (vitamin (A and B) and minerals) and (protein, carbohydrates, fat), and betacarotien of mango fruits which are not conducted in this research due to budget and time limitations, large scale drying room needed.

A detergent for mango fruit sap-induced injury

This study determined the optimum concentration of, and duration of immersion in a local detergent (“awabla”) that protected fruit skin of Kent and Keitt mango varieties from mango fruit sap-induced injury (sap-burn) at harvest.The resultant skin/peel colour, pulp colour, and total soluble solids content was also evaluated for fruit quality. Randomized Complete Block Design and Completely Randomized Design with four replications in each case were used for field and laboratory experiments respectively. For each of the two varieties, ten mango trees were sampled at random in each of the four replications of a mango plantation.On each sample tree, twenty panicles all initiating fruit-set were identified and tagged. The number of days from fruit-set to physiological maturity were monitored and harvested for the experiments. Concentrations of 0.25,0.50, and 0.75% of “awabla” solution for 25,30,and35 minutes immersion period in all combinations were established as appropriate and recommended for management of Kent and Keitt mango fruit sap-induced injury. The detergent (“awabla”) had a proven efficacy in the range of 87-94 % for Kent and 90-93 % for Keitt. The resultant peel colour, pulp colour, and total soluble solids content of Kent and Keitt mango fruit samples were not significantly influenced by the treatments at p&gt;0.05.

Fast field cycling 1H-NMR relaxation properties during convective dehydration of mango fruits

The cultivation of mango fruits is increasing in the Mediterranean areas, including Italy, where a niche production has developed in the Tyrrhenian coast of Sicily. These fruits are rich in antioxidant substances, presenting a pleasant taste and aroma, fundamental qualities for the sensory acceptance of consumers. However, being climacteric fruits, mangoes are highly perishable, due to their rapid ripening after harvesting. As a result, large amounts of mangoes are lost annually in many areas of the world. In order to prevent this, the drying technique is widely used. It allows to lengthen the shelf-life of the fruits. In order to optimize this process, it is necessary to deepen the knowledge on the drying effects on the structure and mobility of the residual water in the fruit. The objective of this paper is to describe the effects of convective drying at different temperatures on the Fast Field Cycling Proton Nuclear Magnetic Resonance (FFC 1H-NMR) relaxation properties, water activity and shrinkage in Keitt mango fruits. The FFC 1H-NMR relaxometry investigations on mango fruits revealed that the convective drying lead not only to a reduction in the overall water content within the mango tissues, but also to a progressive immobilization of the same water, depending on the temperature. From a qualitative and microbiological point of view, the results may indicate that the measure of more immobilised water in the dried fruits can be useful to predict their shelf-life.

Determination of Harvest Maturity for Mango (&amp;lt;i&amp;gt;Mangifera indica&amp;lt;/i&amp;gt; L.) Fruit by Non-Destructive Criteria

Haden, Kent, Palmer, and Keitt mango varieties were studied to establish the relationship of harvest time to 1) seasonal accumulated day-degrees or heat units (˚C), 2) daily rainfall amount (mm), and 3) physical fruit development attributes in order to fix maturity standards for export and local markets. Randomized Complete Block Design with four replications was used. In each case of Haden, Kent, Palmer, and Keitt varieties, physical fruit development attributes established as standard harvest maturity values were: weight (640 g, 836 g, 837 g, and 1104 g, respectively), length (16.31 cm, 16.19 cm, 21.22 cm, and 19 cm, respectively), width (30.97 cm, 33.47 cm, 30.86 cm, and 35.91 cm, respectively), volume (598 cm3, 807 cm3, 772 cm3, and 959 cm3, respectively), density (1.147 g/cm3, 1.076 g/cm3, 1.084 g/cm3, and 1.189 g/cm3, respectively), and indentation (0.25 cm, 0.49 cm, and 0.50 cm, respectively). The intensity of grooves around the stylar-scar end of Palmer fruits was studied and used as maturity index. Index values of 0.075 mls, 0.150 mls, 0.425 mls, and 0.116 mls, respectively, for Haden, Kent, Palmer, and Keitt varieties were recorded as latex exuded at harvest since these values tallied with the other physical harvest maturity index values, and also with those of rain fall and temperature values. Temperature, rainfall, and physical characteristics are therefore important non-destructive criteria for fixing maturity index values for mango fruits.

Physicochemical Attributes in Mango Fruit (Mangifera indica) as Influenced by Storage Temperature and Hot Water Treatment

Background: The temperature being the most important environmental factor that influences the deterioration of perishable commodities. It is often critical that fresh produce rapidly reach the optimal pulp temperature for short term storage if it is to maintain its highest visual quality, flavour, texture and nutritional content (Kader, 2013).&#x0D; Aims: The effects of storage temperature and hot water at various temperature and duration on chemical and textural characteristics of the Keitt mango fruit were evaluated for the 2015/16 growing season in Botswana.&#x0D; Materials and Methods: The treatments were fruits dipped in distilled water at room temperature (25±2ºC- control), fruits dipped in hot water at 50 and 55ºC for a duration of 3, 5 and 10 minutes, and storage temperatures at 4, 7, 10, 13, or 25±2ºC, plus 95% RH.&#x0D; Results: The results showed that as the storage temperature and water temperature decreased, the proline content and electrolyte leakage increased significantly (P ≤ 0.0001). The interactions of storage temperature and hot water temperature, and duration in which mango fruit was treated with hot water, significantly (P ≤ 0.01) maintained vitamin C content, firmness and reduced fruit weight loss during storage and seven days after storage when the fruit was kept at room temperature.&#x0D; Conclusion: Chemical and physical attributes of Keitt mango fruits were significantly improved by the interactions between storage temperature, hot water temperature and duration.

Effect of Hot Water Exposure Duration, Storage and Hot Water Temperature on Chilling Injury, Incidence and Quality of Keitt Mango (Mangifera indica L.)

Low temperature storage is the most effective method of extending postharvest life and maintain fruit quality because it delays physiological processes such as ethylene production and senescence. Unfortunately, fruit such as mangoes are sensitive to low temperature storage and may be detrimental due to chilling injury, which reduces fruit quality. Effects of storage temperature, hot water at various temperatures and durations on alleviation of mango chilling injury and quality were evaluated on Keitt mango for the growing season in Botswana. The treatments were fruits dipped in distilled water at room temperature (25±2ºC- control), dipped in hot water at 50 and 55ºC for duration of 3, 5 and 10 minutes and storage temperatures at 4, 7, 10, 13 and 25±2ºC, plus 95% RH. The results showed that as storage temperature at below 13ºC, chilling injury incidence and severity significantly (P ≤ 0.0001) increased. Atwater temperature from 25ºC to 50 and 55ºC and duration in which mango fruit was held in hot water, increased from 3 to 5 and 10 minutes, chilling injury incidence and severity significantly (P ≤ 0.0001) decreased.

EFECTO DE ASPERSIONES DE BIORREGULADORES EN PRECOSECHA SOBRE EL CRECIMIENTO Y MADURACIÓN DEL MANGO KEITT

En el sur de Sinaloa, México en los municipios El Rosario y Escuinapa se cultivan 21,204 ha de mango (Mangifera indica L.) de las variedades Ataulfo, Tommy Atkins, Kent y Keitt, con producción en 2018 de 195,969 t. El mango Keitt es de interés por ser de maduración tardía (agosto-septiembre). Experiencias empíricas señalan que si se amplía el periodo de cosecha y los frutos tienen mayor vida útil se mejorará la rentabilidad; por ello, se planteó la evaluación del desarrollo y maduración con el uso de giberelinas (AG3 200 mg L-1, Biogib®) y citocininas (Agromil Plus® 2.5 mL L-1), así como un fungicida (Manzate® 2.0 g L-1) para combatir la antracnosis. Los biorreguladores, solos o mezclados, se aplicaron cuatro veces antes de la cosecha en las fechas 3 de mayo, 6 de junio, 2 de julio y 6 de agosto de 2016, cuando los frutos alcanzaron longitudes de 8.1, 10.5, 11.6 y 12.4 cm, respectivamente. Los frutos tratados con Agromil Plus + AG3 + Manzate incrementaron 1.9 cm de diámetro y 3.6 cm en longitud, comparado con los frutos testigo. La caída acumulada de frutos fue alta en el testigo (46 frutos/árbol) y Agromil Plus (50 frutos/ árbol), pero disminuyó con AG3 a 28 frutos/árbol, mientras que la mezcla AG3 + Agromil Plus + Manzate disminuyó a 14.7 frutos/árbol. Dicha mezcla también resultó el mejor tratamiento para mantener la vida útil y reducir la antracnosis de los frutos; así lo muestran los incrementos en firmeza de 95.3 newtons, acidez titulable de 0.21 % de ácido cítrico, reducción en sólidos solubles totales de 3.7 ºBrix, relación SST/acidez en 27 y severidad de antracnosis 24 %, a los 15 d de almacenamiento, comparados con los frutos testigos. El uso de AG3 en precosecha puede mejorar la calidad y la vida útil del mango Keitt cuando se combina con citocininas y se protege a los frutos contra antracnosis con fungicida.

EFECTO DE ASPERSIONES DE BIORREGULADORES EN PRECOSECHA SOBRE EL CRECIMIENTO Y MADURACIÓN DEL MANGO KEITT

In Southern Sinaloa, Mexico, 21,204 ha of mango (Mangifera indica L.) of the Ataulfo, Tommy Atkins, Kent and Keitt cultivars are grown in the municipalities of El Rosario and Escuinapa, with a production in 2018 of 195,969 t. Keitt mango is of interest for being of late ripening (August-September). Empirical experiences indicate that if harvest period is extended and fruits increase their shelf-life, profitability may be improved. Therefore, the evaluation of development and maturation was proposed with the use of gibberellins (GA3 200 mg L-1, Biogib®), cytokinins (Agromil Plus® 2.5 mL L-1) as well as a fungicide (Manzate® 2.0 g L-1) to combat anthracnose. Bioregulators, alone or mixed, were applied four times before harvest on May 3, June 6, July 2 and August 6, 2016, when fruits reached lengths of 8.1, 10.5, 11.6 and 12.4 cm, respectively. Fruits treated with Agromil Plus + GA3 + Manzate increased 1.9 cm in diameter and 3.6 cm in length, compared to the control fruits. The accumulated fall of fruits was high in the controls (46 fruits/tree) and Agromil Plus (50 fruits/tree), but decreased with GA3 to 28 fruits/tree, while the GA3 + Agromil Plus + Manzate mixture decreased to 14.7 fruits/tree. This mixture was also the best treatment to maintain the shelf-life and reduce fruit anthracnose; this is shown by the increases in firmness of 95.3 newton, titratable acidity of 0.21 % citric acid, reductions in total soluble solids (TSS) of 3.7 oBrix, TSS/acidity ratio by 27 and an anthracnose severity by 24 %, at 15 d of storage, compared to the control fruits. The use of GA3 at preharvest may improve the quality and shelf-life of the Keitt mango when combined with cytokinins and fruits are protected against anthracnose with fungicide.