Fertiliser close to the roots could result in scorching. Plants cannot absorb nutrients from a dry soil. Boron deficiency results from excessive leaching, overliming and excessively dry weather.
Concentrations of micronutrients to be used for foliar applications to mangoes are presented in the table. A single spray should be used for minor deficiencies while 2 or 3 sprays should be applied where major deficiencies occur.
Recommended concentrations for foliar sprays Deficient nutrient Treatment B Cu. Leaf sampling A single leaf or soil sample should be representative of an area not greater than 3 ha.
However, if there are soil variations separate leaf and soil samples must be taken and the orchard management adapted accordingly. Sample 7-months-old fully developed hardened-off leaves from fruit-bearing twigs Taking representative soil and leaf samples The time of leaf sampling as well as leaf position, is very important and is shown in the figure.
Leaf analysis is only applicable for producing mango trees normally a tree age of 5 years and older. Select about 20 healthy trees by walking diagonally from the corners through the orchard see figure. The trees should be homogeneous in appearance and representative of the orchard. Exceptionally good or poor trees must not be sampled. The 20 selected trees must be clearly marked, for example with paint, so that both the soil and leaf samples can be taken from the same trees every year.
Where possible, pick 4 leaves from alternate sides of the tree at about shoulder height. Eighty leaves per sample should be sufficient.
Different cultivars should be sampled separately. Leaves sampled must be free of sunburn, disease and insect damage. Leaf samples should be collected in the morning, after the dew has dried off. Leaf samples should not be taken if trees are under stress i.
After a heavy downpour, wait at least 2 weeks before taking samples. After sampling, leaves should be placed in clean, perforated or open plastic bags. If samples cannot be delivered immediately within 48 hours , they can be stored in a refrigerator and should be transported in a cooler bag. The sample must be accompanied by the relevant orchard information including previous production figures, tree age and fertiliser programmes of the past.
Any problems concerning the specific orchard, such as small fruit, should be mentioned. Soil sampling Sampling depth: Topsoil 0 - mm Subsoil - mm Number of samples A sample comprises of a combination of at least 10 subsamples.
A composite sample should not represent more than 3 ha. Samples from different orchards or lands should not be combined. Distribution of sampling points Take samples by walking diagonally from the corner through the orchard or land. In an established orchard, topsoil and subsoil samples should be taken at the same trees selected for leaf sampling. Soil samples must be taken under the canopy of trees in the middle between the stem and the drip area perimeter.
Method of sampling Clear the soil surface of debris, leaves and fertiliser. A soil sample must not be taken too soon after fertilising because this will contaminate the soil sample and lead to an incorrect analysis. The top and subsoil samples are taken by removing a core of soil from the top 0 to mm and then from to mm soil depth, respectively.
Packaging of samples Subsamples from an orchard or land should be combined in the respective bucket not a fertiliser bag and mixed thoroughly. A sample of about 2 kg is taken from the composite sample and dispatched in a clean, strong bag. Weed control Weeds are usually controlled between rows in an orchard by means of mechanical mowing with a rotary cutter slasher driven by a tractor.
Chemical mowing, where herbicides are used, can be applied at low concentrations as an alternative. The idea is not to kill all the weeds but to slow down growth. Chemical control is normally followed by mechanical mowing. The advantage of this method is that mechanical mowing is limited, resulting in less traffic in the orchard.
Diseases Anthracnose It is an important post-harvest fungal disease which affects all mango cultivars to varying degrees. Because the disease is rain-linked, the fruit will be less affected in warm areas where it matures early and where it does not hang on the trees throughout the rainy season.
Symptoms Small brown-black spots appear on the leaves, which could later enlarge and coalesce to form large blackened irregular patches, usually with a faint yellow halo. The tissue will die and later fall out.
Control During wet periods control measures are important, especially when the trees are in bloom, to prevent losses as a result of blossom blight and also during fruit development to reduce post-harvest problems.
Specific sprays for anthracnose are not usually necessary because the fungus is controlled by the fungicide programme followed for powdery mildew and bacterial black spot. Powdery mildew This is a fungal disease found in all mango-growing areas and in the case of all cultivars. It is usually a lesser problem in areas with warm winters.
Symptoms Infection starts as isolated white powdery patches on young tissue of the shoots, leaves, flowers or fruit. Once a certain stage of maturity is reached, the fruit is no longer susceptible. Infected flowers fail to open and drop from the inflorescence without fruit formation. On small fruit pea size , mildew causes skin cracking and corky tissue. Younger fruit will drop. After the fruit matures beyond marble size there are no longer a risk.
White powdery patches can occur on young leaves which then curl and become distorted. As the leaf matures and the fungus disappears, brown patches remain. Mature leaves are not susceptible. Control Various fungicides are registered for effective control.
Bacterial black spot Symptoms Bacterial black spot is a rain-related disease. Fruit lesions begin as water-soaked spots which later become raised and black cracking open to exude a gum-containing bacterium.
There is often a tear-stain pattern where the gum has washed down the fruit and started a number of new lesions. Infection of small fruit and especially the fruit stalk will cause fruit drop.
Control Copper sprays are the only method of combating the disease and are not always successful when disease prevalence is high. One or two post-harvest copper sprays to cover the post-harvest flush and final stage of the rainy season are effective in reducing inoculum pressure during the following summer. Malformation It is a fungal disease which is spread by grafting and buying infected trees from nurseries.
Blossom malformation is easy to control, but if left unchecked can devastate an orchard. Symptoms Affected flowers look like cauliflower heads. The axes of the panicles are shorter and thicker than normal, branch more often, and a profusion of enlarged flowers is produced. These panicles develop more slowly than normal, retaining their green colour but the flowers are mostly sterile. If this is done every year the incidence of the disease becomes insignificant.
Pests Fruitflies Mangoes can be severely damaged by female fruitflies laying eggs in the fruit and by the maggots larvae which then develop in the flesh of the fruit.
Control Successful fruitfly control in mango orchards depends on a combination of the following: Eradication of invaders host plants such as bug tree and brambles. Orchard and yard sanitation by removing on a regular basis all mangoes and other fruit that have dropped in the orchard or yard and destroying these immediately.
The use of traps to determine when a population build-up occurs. By making weekly counts of the number of flies in the traps, a sudden increase in the population can be detected and chemical control can commence. Regular poison bait applications.
Chemical control of adult fruitflies in mango orchards are based on weekly applications of a poison bait on the trees. The poison bait contains a mixture of insecticide plus a lure plus water.
Directorate Communication. September: 50 mm November: mm January: mm. October: 85 mm December: mm February: mm. Standard semi-intensive planting a degree of manipulation manipulation is still necessary m. Intensive planting for specific training system, manipulation techniques, rootstocks and soil types m. Each flower is small with white petals and a mild sweet aroma. The flowers are pollinated by insects and less than 1 percent of the flowers will mature to form fruit.
A mango fruit tree in full flower in the optimal mango tree growing zone is a beautiful sight indeed. In certain varieties, the mangos that receive the most sunlight will develop a red blush at the stem end.
This red blush is not an indicator of maturity, quality or ripeness. During that time, the fruit-laden branches of the mango tree may bow under the weight of the developing mangos. Each fruit is harvested by hand, providing jobs for local workers and a safe passage to the packinghouse for the mangos. Another important piece of mango tree information is that its growth causes a process called carbon sequestration or carbon uptake. The tree absorbs carbon dioxide from the environment in mango tree climate zones around the world, using it to form the trunk, branches, leaves and fruit of the mango tree.
The tree produces oxygen and releases it into the environment during this process. Meanwhile, the process of growing, harvesting and transporting the mangos to the retailer in the U. USDA Mangos, raw. Supply Chain Management and Ripening. Culinary Education.
Mango Nutrition. The supercharged superfruit. Mangos pack a nutritional punch. There are calories in 1 whole mango without refuse and g. Each serving of mango is fat free, sodium free and cholesterol free.
Mangos contain over 20 different vitamins and minerals, helping to make them a superfood.
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