Morphoagronomic and isoenzymatic evaluation and selection of Leucaena spp. accessions for silvopastoral purposes

 


Hilda Beatriz Wencomo Cárdenas
Estación Experimental de Pastos y Forrajes Indio Hatuey Central España Republicana 44280, Matanzas, Cuba

 

ABSTRACT
In order to select the most outstanding accessions to be studied in the development of new areas in which silvopastoral systems are used, 23 Leucaena spp. accessions were evaluated, including five species: L. leucocephala (11), L. lanceolata (3), L. diversifolia (2), L. macrophylla (5) and L. esculenta (2), through morphoagronomic indicators and the technique of enzyme electrophoresis, at the Pastures and Forages Research Station “Indio Hatuey”, Matanzas. The results showed that the indicators that best defined the variability of the evaluated accessions were: under nursery conditions: plant height, number of leaf sprouts, dry biomass of the aerial part, length and dry mass of the root; in the establishment stage: plant height, stem diameter, number of branches, dry matter yield; in the recovery capacity after pruning: number of regrowths, their length, stem diameter, number of branches and yield and in the selection of species: height, stem diameter, number of branches, yield, biomass availability (edible and woody) and crude protein content. The species and accessions of this genus, in general, showed high recovery capacity after pruning. The analysis of isoenzymatic patterns allowed to differentiate the species L. leucocephala more clearly than the others, although the differentiation within the species and the differences among accessions could not be detected; the esterases were the most polymorphic ones. It was proven that there were no duplicated genotypes in the analyzed germplasm collection. The results allowed to select the accessions L. leucocephala CIAT-9119, CIAT-9438, CIAT-751, CIAT-7988, CIAT-7384, CIAT-7929, CIAT-17480, L. lanceolata CIAT-17255, CIAT-17501 and L. diversifolia CIAT-17270, to be studied in the development of new areas with silvopastoral systems and the ones which were not selected to be used in these systems were proposed for other purposes (shade trees, windbreaks, living fences or as green manure due to the easy decomposition of their leaves and their N content). It is recommended to introduce these results in the undergraduate and postgraduate programs of college schools, research centers and agricultural polytechnic schools.