Caracterização anatômica e histoquímica foliar de Desmanthus spp. em sequeiro no Semiárido pernambucano

• Ano de defesa: 2017
• Autor(a) principal: Cavalcanti, Hactus Souto
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal da Paraíba; Brasil; Zootecnia; Programa de Pós-Graduação em Zootecnia; UFPB
• Palavras-chave em Português: Jureminha – Anatomia vegetal; Desmanthus – Caracterização foliar; Caatinga; Leguminosa; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA
• Link de acesso: https://repositorio.ufpb.br/jspui/handle/123456789/15875

The Northeast region of Brazil has a predominance of semiarid climate. In this region there is a variety of endemic species, highlighting the jureminha (Desmanthus pernambucanus (L.) Thellung), legume forage that shows desirable characteristics to animal production. The aim of this study was characterize anatomic and histochemically three genotypes (7G, 50J and 13AU) to identify structures that explain the superior performance of 7G genotype. The material was collected in experimental field of the Academic Unit of Serra Talhada (UAST/UFRPE) in dry season. Biomass production of genotypes were the basis for selection, in which were collected the leaves of the maximum (7G), intermediate (50J) and minimum (13AU) production. The leaves were collected on the 1º and 3º branch node (apex-base direction), considering the ages in young and mature. These leaves were fractionated in 5 parts (petiole, extrafloral nectary, rachis, petiolule and leaflet), fixed in FAA 50%, dehydrated in increasing alcoholic series and embedding of samples in LEICA® historesin. The slides were stained with toluidine blue for anatomical description. It were made histochemical tests to identify starch, protein granules, lipids, phenolic compounds, lignin, condensed tannins, alkaloids and terpenoids. Petiole morphology was variable within genotypes and leaves studied, with higher total area in both leaves of 7G genotype. Extrafloral nectary and petiolule showed similar morphology in studied genotypes. The rachis was similar in 7G and 50J, in both leaves, whereas 13AU was different. The leaflet showed a single layer of epidermal cells and dorsiventral mesophyll, except in young leaflets of 7G and 50J genotypes, which was characterized as homogeneous. In all fractions measured the area occupied by vascular bundles was higher in 7G genotype when compared to others. Histochemical tests to alkaloids, condensed tannins and terpenoids were negative. It was observed the presence of starch, protein granules, lipids, phenolic compounds and lignin in several tissues studied. Amyliferous sheath was observed around vascular bundle of petiole in all genotypes, characterizing the endoderm as well as in cortical and/or pith parenchyma of other fractions. Protein granules were observed in all genotypes, except in leaflets of 7G, in petiole and extrafloral nectary of mature leaflet of 50J and 13AU. It was verified the presence of lipids constituting the in all fractions evaluated. Phenolic compounds occurred, mostly, in epidermis and/or cortical parenchyma of petiole, extrafloral nectary, rachis and petiolule. It was observed lignin in all the genotypes, except in leaflet of young leave from 7G. This compound was located in sieve elements of xylem and sclerenchyma fibers. There is anatomical characteristics that justify the higher productivity of 7G genotype in comparison to others. The histochemical results shows the acclimation of native plants from Caatinga, considering the many sources of stress in this environment.