Coffee Science - v.13, n.4, 2018

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/11109

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Initial productive performance of coffee progenies in an area infested by Meloidogyne paranaensis
(Editora UFLA, 2018-10) Santos, Henrique Frederico; Salgado, Sonia Maria de Lima; Mendes, Antônio Nazareno Guimarães; Carvalho, Alex Mendonça de; Botelho, Cesar Elias; Andrade, Vinicius Teixeira
In this study, we aimed to carry out a selection of Coffea arabica progenies in areas infested by Meloidogyne paranaensis in order to select materials that are resistant to this nematode, with desirable agronomic characteristics. The experiment was set on Guaiçara Farm, located in the Municipality of Piumhi – MG, in February 2012. Twenty-one coffee progenies were evaluated in the F5 generation and 5 commercial cultivars were used as a control. A randomized complete block design was used, with three replicates, totaling 78 plots, consisting of eight plants each. The spacing used was 3.00 x 0.50 m in the rows and between plants, respectively. The populations of M. paranaensis per gram of coffee roots, productivity (bags. ha-1 ), plant vigor, maturation cycle, maturation uniformity, coffee ranking by grain size (sieve 17 and above), and classification of mocha coffee were evaluated. It was concluded that progenies MG 0179-3-R1-151 and MG 0185-2-R2-132 are resistant to M. paranaensis and have good agronomic characteristics in an area naturally infested by this nematode, thus indicated for plantations in this situation. Nine progenies reveal tolerance/resistance characteristics to M. paranaensis.
Models identity generated in neutron probe calibration in latosol cultivated with coffee and signalgrass
(Editora UFLA, 2018-10) Borges, Inácio Barbosa; Rocha, Omar Cruz; Malaquias, Juaci Vitória; Fagioli, Marcelo; Sá, Marcos Aurélio Carolino de; Guerra, Antônio Fernando
The cover plants affects soil spatial variability interfering with soil moisture and density, leading to doubts about the need for calibration of the neutron probe for different management systems. The objective of this study was to evaluate the Model Identity Method in the verification of equality of linear regressions resulting from the calibration of a neutron probe for different layers, as a function of signalgrass management as a cover crop between rows of soil coffee crop in the Brazilian Central Cerrado. Aluminum tubes were installed to access the probe and two saturation basins were built in a coffee area, irrigated by a central pivot, in an Oxisol, with two management systems, T (Traditional with bare soil) and Sg (Signalgrass in the row). Samples were taken at depths of 0-0.20; 0.20-0.40; 0.40-0.60; and 0.60-0.80 m for determination of gravimetric moisture and density, and the volumetric moisture was determined to follow the drying of the soil. Concomitantly, measurements were taken with the neutron probe in these layers. Two calibration curves were constructed for each layer, which were compared by the above method. It was observed that treatment Sg yielded differences in soil water storage in the 0.20- 0.40 m layer, differing from treatment T. The statistical method allowed the observation of equality of regressions between treatments Sg and T at depths 0-0.20, 0.40-0.60, and 0.60-0.80 m; it also showed the need for different regression curves per layer, besides justifying the need for neutron probe calibration for each specific local condition.
Sprouting induction for micro-cutting on in vitro cloned arabica coffee plants
(Editora UFLA, 2018-10) Angelo, Paula Cristina da Silva; Ferreira, Iran Bueno; Reis, André Moraes; Bartelega, Lucas; Carvalho, Carlos Henrique Siqueira de; Paiva, Ana Carolina Ramia Santos; Matiello, José Braz
Vegetative propagation of arabica coffee plants selected by their agronomic value has been accomplished routinely in Brazil for scientific purposes, through somatic embryogenesis and rooting of stem cuttings. Somatic embryogenesis is the election method when a very high number of cloned plants is demanded. Nevertheless, the costs of in vitro multiplication make difficult to explore it commercially. The experiments described herein aimed to amplify the number of in vitro cloned plants, post acclimatization, to reduce costs. Different concentrations of 2,3,5-triiodobenzoic acid (TIBA) and its association with benzylaminopurine (BAP) were applied, as successive pulses, in the 3 rd , 8 th and 13 th months after transference to the greenhouse, on the same set of Catucaí and Siriema in vitro cloned plants, to induce sprouting. At the 8 th month, the experiments with in vitro cloned Catucaí plants were reproduced in the nursery, for comparison. Best results were observed for the association TIBA 1000 mg.mL-1 + BAP 60 mg.mL-1 applied in the greenhouse, at the 13 th month, when, on average, 8.5 and 7.0 micro-cuttings above 1 cm in length were produced using sprouts taken from each Catucaí and Siriema acclimatized plant, respectively. Applying this treatment twice a year, and harvesting induced sprouts each six months after the induction treatments, approximately 15 plants per each acclimatized one can be produced. The most important effect of TIBA was the induction of sub-apical sprouting. Greenhouse would be the best environment to apply successive pulses of sprouting inducers to coffee in vitro cloned plants.