User:Caecusvanarbus/sandbox

Cultivation and Orchard-Management

The vegetative propagation of Carob is restricted due to it's low adventitious rooting potential, which could be improved by using better grafting-techniques such as air-laying . Therefore seeds are still widely used as the propagation medium. The sowing occurs in pot nurseries in early spring and the cooling- and drying-sensitive seedlings are then transplanted to the field in the next year after the last frost. Carob trees enter slowly into production phase. Where in areas with good growing conditions the cropping starts 3-4 years after budding, the nonbearing period can take up to 8 years in regions with marginal soils. Full bearing of the trees occurs mostly at a tree-age of 20-25 years where the yield stabilizes . The orchards are traditionally planted in low densities of about 25-45 trees/hectare. Hermaphrodite plants or male trees, which produce no or fewer pods respectively, are usually planted in lower densities in the orchards as pollenizer.
Intercropping with other tree species is widely spread. There is not much cultivation management required. Only light pruning and occasional tilling to reduce weeds is necessary. Nitrogen-fertilizing of the plants has been showed to have positive impacts on yielding-performance .

Pests and Diseases

There are only few pests known to cause severe damage in carob orchards therefore it has traditionally not been treated with pesticides. Some generalist pests like the larva of the leopard moth (Zeuzera pyrina L.), small rodents like rats (Rattus spp.) and gophers (Pitymys spp.) can cause damage occasionally in some regions. Only some cultivars are severely susceptible to mildew disease (Oidium ceratoniae C.). One pest directly associated with carobs is the larva of the carob moth (Myelois ceratoniae Z.) which can cause extensive post-harvest-damage.

Cultivars and Breeding-aims

Most of the approximately 50 known cultivars are of unknown origin and only regionally distributed. The cultivars show high genetic and therefore morphological and agronomical variation. No conventional breeding by controlled crossing has been reported but there has been done selection from orchards or wild populations. Domesticated carobs (var. edulis) can be distinguished from their wild relatives (var. silvestris) by some fruit-yielding traits like building of greater beans, more pulp and higher sugar contents. Also there was an genetic adoption of some varieties to the climatic requirements of their growing-regions . Though there was a partially successful breaking of the dioecy, the yield of hermaphroditic trees still can't compete with that of female plants as their pod-bearing properties are worse . Future breeding would be focused on processing-quality-aspects as well as on properties for better mechanization of harvest or better yielding hermaphroditic plants. The use of modern breeding techniques is restricted due to low polymorphism for molecular markers.