01. CAROB AND ITS FRUIT
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1.1 Carob tree physiology
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1.1 Carob tree physiology: growth and reproduction biology
THERESIA TERESA TZATZANI
Agronomist, Researcher, Institute of Olive, Subtropical Plants and Vine, ELGO DIMITRA
Carob tree is an evergreen tree, medium to large, that can reach 10m height. It has a spherical crown, with lateral vegetation and strong shoots with rough bark. It is dioecious tree, ie each plant has only male or female flowers. Male and female trees are installed in certain ratio in commercial plantations, for better pollination, fruiting and yield. It is considered to be a species of hot and dry regions that can thrive in areas with subtropical climate. The vegetative growth of carob tree decreases at temperatures below 10 oC and shows relative frost sensitivity, but has an excellent resistance to high temperatures. It thrives in a wide range of soils and can utilize poor and degraded soils as well.
The main propagation technique is grafting on wild native trees or seedlings. Seed germination faces several difficulties and special manipulations are required, which include hydration, immersion in hot water, etc. In case of non-grafted trees, the seedlings reach reproductive age after the 8th year. Flowering begins in late summer and lasts throughout the fall. The flowers are pollinated by the wind. Adverse environmental conditions during the flowering period, can affect fruit set. Fruit development begins after fertilization and the fruit ripening is completed in August of the following year and can be observed by the change of color from green to brown, the reduction of humidity in the fruit and the increase of sugars.
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1.2 CAROB COMPONENTS
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1.2 Carob components
HARIS KATERINOPOULOS
Chemist, Professor, Department of Chemistry, University of Crete
Crete has one of the richest flora in the Mediterranean region. Of the approximately 1800 plant species of Crete, 180 are endemic.
Carob (Ceratonia siliqua L.) has been known in Greece since antiquity as one of the main export products of Crete. C. silica and its subspecies are characterized by groups of components, which constitute their chemical fingerprint. Thus it is possible to define the Chemotaxonomy of the subspecies and their differentiation.
Recent data1 indicate that the fruit is a mixture of primary and secondary metabolites, with a characteristic presence of sugars and fiber.
Sucrose is the major carbohydrate followed by fructose and glucose. The main cyclitol is D-pinitol with only traces of myo-inositol, D – (+) – chiro-inositol, onnitol, sequoitol, and bornesitol.
Phenolic, mainly benzoic and cinnamic acid derivatives, are the most abundant class of polyphenols with gallic acid and methyl galllat being the main representatives.
The fruits are particularly rich in flavonols such as quercetin, myricetin, kaempferol and their glycosides. They also contain tannins and a mixture of 17 amino acids with aspartate, asparagine, alanine, glutamate, leucine and valine accounting for 57% of the pod content which is also an excellent reservoir of potassium and calcium.
Bibliography
1) Goulas, V. et al., 2016, Int. J. Mol. Sci.17,1875 -
1.3 Cultivation methods
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1.3 Cultivation methods, problems and coping techniques
THERESIA - TERESA TZATZANI
Agronomist, Researcher, Institute of Olive, Subtropical Plants and Vine, ELGO DIMITRA
Carob tree is planted in squares or rows, at distances between 8 and 10m and at a density of 11 to 16 trees per acre. During the installation, seedlings are planted with a soil ball and regular watering is required, at least during the first year. In a commercial plantation, in areas with a limited rainfall, irrigation is recommended from late spring to autumn. It is also advised to support the young trees for wind resistance.
Although carob tree is considered a species with limited nutritional requirements, fertilizers should be applied on an annual basis to achieve better yield. Manure addition in soil and weed control, provides multiple benefits to the crop. Especially weed incorporation in soil, contributes to the improvement of the soil structure, increase of the organic matter, better absorption of water and reduction of the risk of fire.
Carob tree does not require pruning on an annual basis to bear fruit, like other fruit trees, but for disease prevention a careful pruning is recommended and along with offshoots trimming.
An important enemy of the carob tree are the rodents, which in their attempt to find water, can remove part of the bark, especially on young trees. Harvesting takes place from late summer to early autumn, manually or by mechanical means. As the harvest often coincides with the flowering time, careful handling is required.
1.1 Carob tree physiology: growth and reproduction biology
THERESIA TERESA TZATZANI
Agronomist, Researcher, Institute of Olive, Subtropical Plants and Vine, ELGO DIMITRA
Carob tree is an evergreen tree, medium to large, that can reach 10m height. It has a spherical crown, with lateral vegetation and strong shoots with rough bark. It is dioecious tree, ie each plant has only male or female flowers. Male and female trees are installed in certain ratio in commercial plantations, for better pollination, fruiting and yield. It is considered to be a species of hot and dry regions that can thrive in areas with subtropical climate. The vegetative growth of carob tree decreases at temperatures below 10 oC and shows relative frost sensitivity, but has an excellent resistance to high temperatures. It thrives in a wide range of soils and can utilize poor and degraded soils as well.
The main propagation technique is grafting on wild native trees or seedlings. Seed germination faces several difficulties and special manipulations are required, which include hydration, immersion in hot water, etc. In case of non-grafted trees, the seedlings reach reproductive age after the 8th year. Flowering begins in late summer and lasts throughout the fall. The flowers are pollinated by the wind. Adverse environmental conditions during the flowering period, can affect fruit set. Fruit development begins after fertilization and the fruit ripening is completed in August of the following year and can be observed by the change of color from green to brown, the reduction of humidity in the fruit and the increase of sugars.
1.2 Carob components
HARIS KATERINOPOULOS
Chemist, Professor, Department of Chemistry, University of Crete
Crete has one of the richest flora in the Mediterranean region. Of the approximately 1800 plant species of Crete, 180 are endemic.
Carob (Ceratonia siliqua L.) has been known in Greece since antiquity as one of the main export products of Crete. C. silica and its subspecies are characterized by groups of components, which constitute their chemical fingerprint. Thus it is possible to define the Chemotaxonomy of the subspecies and their differentiation.
Recent data1 indicate that the fruit is a mixture of primary and secondary metabolites, with a characteristic presence of sugars and fiber.
Sucrose is the major carbohydrate followed by fructose and glucose. The main cyclitol is D-pinitol with only traces of myo-inositol, D – (+) – chiro-inositol, onnitol, sequoitol, and bornesitol.
Phenolic, mainly benzoic and cinnamic acid derivatives, are the most abundant class of polyphenols with gallic acid and methyl galllat being the main representatives.
The fruits are particularly rich in flavonols such as quercetin, myricetin, kaempferol and their glycosides. They also contain tannins and a mixture of 17 amino acids with aspartate, asparagine, alanine, glutamate, leucine and valine accounting for 57% of the pod content which is also an excellent reservoir of potassium and calcium.
Bibliography
1) Goulas, V. et al., 2016, Int. J. Mol. Sci.17,1875
1.3 Cultivation methods, problems and coping techniques
THERESIA - TERESA TZATZANI
Agronomist, Researcher, Institute of Olive, Subtropical Plants and Vine, ELGO DIMITRA
Carob tree is planted in squares or rows, at distances between 8 and 10m and at a density of 11 to 16 trees per acre. During the installation, seedlings are planted with a soil ball and regular watering is required, at least during the first year. In a commercial plantation, in areas with a limited rainfall, irrigation is recommended from late spring to autumn. It is also advised to support the young trees for wind resistance.
Although carob tree is considered a species with limited nutritional requirements, fertilizers should be applied on an annual basis to achieve better yield. Manure addition in soil and weed control, provides multiple benefits to the crop. Especially weed incorporation in soil, contributes to the improvement of the soil structure, increase of the organic matter, better absorption of water and reduction of the risk of fire.
Carob tree does not require pruning on an annual basis to bear fruit, like other fruit trees, but for disease prevention a careful pruning is recommended and along with offshoots trimming.
An important enemy of the carob tree are the rodents, which in their attempt to find water, can remove part of the bark, especially on young trees. Harvesting takes place from late summer to early autumn, manually or by mechanical means. As the harvest often coincides with the flowering time, careful handling is required.
