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Much attention is currently being paid to the issues of seed production of forest species. In order to improve the forest-seed business in desert forests, it is advisable to create permanent forest-seed plots (PFSP), which should form a seed bank providing forestry with high-quality seeds with genetically healthy traits. This makes it possible to concentrate seed collection in the PFSP, improve the mold composition of seed plantations, increase yields and their quality. It is relevant that when creating new PFSP or choosing plus trees in massive plantings, it is possible to switch to a breeding basis by sowing seeds or planting varietal material with certain hereditary characteristics. In the early stages of afforestation of the drained bottom of the Aral Sea, saxaul plantations were created by seeds collected in the Kyzylkum desert from plus trees, where a form of saxaul resistant to pests and diseases of the forest was selected. This form of saxaul was introduced into the extreme conditions of the drained bottom, as a result of which an eco-form of saxaul was developed that is resistant not only against pests and diseases, but also tolerates stronger salinization of soils and their aridity. As a result of the selection of saxaul, currently the fifth generation of plants grows on the drained bottom, adapted to the conditions of the drained bottom and having faster growth. So, at the age of 8 years, saxaul plants reach up to 5 m in height and a crown diameter of about 400 cm [1]. These are the saxaul plantings that serve as permanent forest-seed plots, where seed harvesting is currently taking place. The relevance of the work is expressed in the increased need of forestry enterprises for high-quality seeds with genetically stable traits necessary for large-scale forest reclamation work on the drained bottom of the Aral Sea. The purpose of the work was to allocate forest plantations of the black saxaul with high genetic characteristics for PFSP in order to create a solid forest seed base for forest reclamation production on the drained bottom of the Aral Sea. 20,000 hectares of forest plantations were surveyed, of which 14,316 hectares of saxaul plantations with good genetic characteristics and resistant against pests and diseases were identified. It has been experimentally established that in order to obtain high seed yields, saxaul plantings should have a crown closure of no more than 0,2–0,3 units. |
