Atributos radiculares, foliares e produtivos em diversos genótipos cultivados de Coffea canephora Pierre ex Froehner

• Ano de defesa: 2022
• Autor(a) principal: Schmidt, Raquel
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Doutorado em Genética e Melhoramento; Centro de Ciências Agrárias e Engenharias; UFES; Programa de Pós-Graduação em Genética e Melhoramento
• Palavras-chave em Português: Raízes; Melhoramento genético; Agrupamentos; subject.br-rjbn; Melhoramento Vegetal
• Link de acesso: http://repositorio.ufes.br/handle/10/16084

The objective of this work was to study the root system in the soil profile of 16 robusta coffee genotypes cultivated in the Brazilian Amazon and to estimate the genetic parameters. The evaluations took place in Alta Floresta D'Oeste, Rondônia, Brazil. A volume of 27 cm3 of soil and roots was collected separately at every 10 cm depth up to 60 cm, and removed at a standard distance of 30 cm from the plant stem in the planting row of 16 robusta coffee genotypes. The roots obtained were washed, digitized and processed in the Sapphire program, and the root volume per soil volume, surface area, diameter and length of the roots were quantified. Then they were grouped by the hierarchical method UPGMA and Toucher. The characteristics of the aerial part of the plant were evaluated and correlated with the characteristics of the roots. The root system of the 16 genotypes was mainly concentrated in the layer 0 – 30 cm of the soil, comprising 80% of the root volume. The LB015 genotype showed greater root volume in the layers up to 30-40 cm. The largest volumes presented in the 50-60 cm layer were from the AS10 and AS4 genotypes with values 36.24 and 55.13 (mm³ cm-3), respectively. The heritability indexes (h²) obtained values close to 100%. Through UPGMA and Toucher analysis, it was possible to group the genotypes into four groups, with LB015 remaining isolated (group IV). Positive correlations were observed between the characteristics of the root system. The root system of the 16 evaluated genotypes was mainly concentrated in the 0 – 30 cm layer of the soil, comprising 80% of the root volume. However, nine genotypes can be considered promising for genetic improvement aiming at tolerance to water deficit, as they present greater volumes of roots in the deeper layers of the soil, having been grouped in a separate group of the diversity analysis.