Avaliação morfológica de sementes crioulas arroz (Oryza Sativa L.) Pertencentes à coleção da Universidade Estadual do Maranhão- UEMA.

Abstract

Rice (Oryza sativa L.) is an annual grass that grows well in flooded and dry soils, with adapted roots. The grain, composed of endosperm and embryo, is protected by a silica-rich shell. After harvest, the seeds enter dormancy, with a duration that varies depending on the cultivar. Federal Law No. 10,711/2003 recognizes creole seeds, local varieties developed by family farmers and traditional communities. The conservation, characterization and evaluation of germplasm are essential to develop more resistant and adapted cultivars, ensuring the sustainability of agricultural production in the face of constantly changing environmental conditions. The present work aims to characterize and morphologically describe the seeds of landraces of rice (Agulha Vermelha, Fininho Vermelho, Ligeiro Vermelho, Macuxi, Cana Roxa, Marabá, Comum, Quechi, Vital and Fininho Branco), kept in the Seed Collection of State University of Maranhão, collected in the state. The evaluations were carried out in the Phytopathology and Seed Laboratories, observing unhulled rice seeds, characterized by the pubescence of the glumellas, through visual assessment of their presence and distribution. The shelled seeds were evaluated for the color of the pericarp with the help of the color chart, and biometry was carried out, measuring the dimensions of the seeds, classifying them and correlating them with the evaluation of the weight of a thousand seeds. The study on the external morphological characterization of pubescence in indigenous rice seeds reveals that a large percentage of them are smooth, with an incidence of hairs on the central lemma and short hairs, influencing aspects such as resistance to pests and ease of processing. The use of the Munsell classification provides greater accuracy in identification and differentiation, with coordinates varying from light brown to white based on the color of the pericarp. Varieties classified as long thin include Fininho Vermelho, Marabá, Fininho Branco, Macuxi and Vital. Varieties with a varied distribution of lengths are Agulha Vermelha, Ligeiro Vermelho and Comum, while short seeds include Cana Roxa and Quechi. Seed detailing, together with weight assessment, is essential for the accurate identification of varieties and for the implementation of agricultural and conservation initiatives for indigenous rice seeds in the state of Maranhão