Navegando por Autor "Giuriatto Júnior, Jurandyr José Ton"

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Growth and physiological quality in clonal seedlings of Robusta coffee
(Universidade Federal do Ceará, 2020) Giuriatto Júnior, Jurandyr José Ton; Espindula, Marcelo Curitiba; Araújo, Larissa Fatarelli Bento de; Vasconcelos, Jaqueline Martins; Campanharo, Marcela
The intrinsic characteristics of the vegetative propagule may influence the rooting speed and shoot growth, as well as the final physiological quality of clonal seedlings of Coffea canephora. The aim of this study was to evaluate the growth and physiological quality of ‘Robusta’ coffee seedlings produced from propagules (stem cuttings) with different cutting ages. The study was conducted in a greenhouse, in the district of Ouro Preto do Oeste, in Rondônia, Brazil (10˚45’43” S and 62˚15’10” W). The ages of the cuttings were 30, 60, 90, 120 and 150 days, corresponding to five positions on the secondary orthotropic stem (sprout), from the apex to the base. Dry matter accumulation, and relative and absolute growth rates were evaluated for 188 days after cutting, as well as the vegetative characteristics of the seedlings at 125 days after cutting. It appears that growth can be divided into three phases: 1) Initial: slow growth, lasting approximately 83 days; 2) Intermediate: fast growth, lasting approximately 40 days; and 3) Final: slow growth, starting approximately 125 days after cutting. With physiological quality, although all the cuttings showed similar growth curves, those of 60, 90 and 120 days produced, 125 days after cutting, the best vegetative performance in the seedlings.
Nutrient content and cutting anatomy can affect the production of Conilon clonal plantlets
(Editora UFLA, 2024-09-19) Bazoni, Patricia Alves; Espindula, Marcelo Curitiba; Araújo, Larissa Fatarelli Bento de; Vasconcelos, Jaqueline Martins; Giuriatto Júnior, Jurandyr José Ton; Campanharo, Marcela
Cutting is the main vegetative propagation method used to produce Coffea canephora plantlets. In this method, the nutritional quality of the vegetative propagule (stem cuttings) is one of the determining factors for the rooting speed and the final quality of the plantlets. Thus, the objective in this study was to verify possible variations in nutrient content and anatomical characteristics in cuttings collected at different times of the year and their relationship with the production of Coffea canephora clonal plantlets. The study was divided into two phases: 1) Nutritional composition and anatomy of C. canephora cuttings grown at different times; 2) Production of C. canephora seedlings under greenhouse conditions. The treatments consisted of cuttings collection and plantlets production at different times of the year: January, May and September 2017. We observed that there is seasonal variation for the content of N, P, K and Mg; and anatomical changes in xylem, phloem and vascular cylinder thickness in cuttings harvested at different times of the year. We conclude that although nutritional and anatomical aspects of the vegetative propagule may result in different vegetative growth rates of C. canephora clonal plantlets, this result is more dependent on the management of the nursery environment conditions, especially temperature and relative air humidity.