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de Rezende J.C.,Unidade Regional do Sul de Minas Uresm | de Carvalho C.H.S.,Embrapa Cafe Fundacao Procafe | Pasqual M.,Federal University of Lavras | Santos A.C.R.,Embrapa Cafe Fundacao Procafe | de Carvalho S.M.,Claro
Ciencia Rural | Year: 2011

Three experiments were carried out with the objective of achieving high effectiveness in calli induction from high heterozygosis leaf explants of Coffea arabica through indirect somatic embryogenesis. A randomized-block design in a 2x5 factorial arrangement made up of two media [BOXTEL & BERTHOULY (1996) and TEIXEIRA et al. (2004)] and five C. arabica genotypes were used in the first experiment. In the second experiment the embryogenic calli production potential was evaluated in ten genotypes. Each of them was considered as a treatment. In the third experiment the variations in both 2.4-D (2.5 e 20μM) and 2-iP (2.5 e 20μM) concentrations in TEIXEIRA et al. (2004) medium and secondary media were evaluated. Crops were kept in a growth room under darkness, at 25±2°C. The medium described by TEIXEIRA et al (2004) was found to be superior when compared to that described by BOXTEL & BERTHOULY (1996) in the 2.2 and 7.2 genotypes. An opposite behavior was noticed in 4.2 genotype, that is, BOXTEL & BERTHOULY (1996) had medium superiority. Both 3.0 and 5.0 genotypes had the same behavior in both media studied, which shows that the somatic embryo production depends on the genotype. Calli induction depends on the 2-iP and 2.4 D ratio. The 20.0μM of 2.4-D and 20.0μM of 2-iP combination caused the highest embryogenic calli induction rate. Source

de Paiva R.F.,Federal University of Lavras | Mendes A.N.G.,Federal University of Lavras | Carvalho G.R.,Unidade Regional do Sul de Minas Uresm | de Rezende J.C.,Unidade Regional do Sul de Minas Uresm | And 2 more authors.
Ciencia Rural | Year: 2012

This research had the objective to evaluate the effect of grafting and 'Apoatã IAC 2258' cv. as rootstock on agronomic performance of seven Coffea arabica cvs. planted in area nematodes free. The experimental design was randomized blocks using a 7x3 factorial scheme with four repetitions. The treatments were 'Obatã IAC 1669-20', 'Acauã', 'Oeiras MG 6851', 'Catucaí Amarelo 2SL', 'Topázio MG 1190', 'IBC Palma II' and 'Paraíso MG H 419-1' coffee cultivars grafted on 'Apoatã IAC 2258', self grafted (meaning a cultivar was grafted on a rootstock of the same cultivar) and no grafting. The characteristic evaluated was the average yield of beans between the first and the fourth year, the fruit maturation stage, floating grain percentage and the bean size. The grafting cultivars showed good agronomic performance in the characteristic evaluated. The performance in coffee cultivars grafted on 'Apoatã IAC 2258' is the same in no grafting. In nematodes free areas, with the exception of the cultivars 'IBC Palma II' and 'Paraíso MG H 419-1', all cultivars are good choices to be used as scions. The grafting technique using 'Apoatã IAC 2258' as rootstock on area free of nematodes is not justified for yield increase. Source

Rezende R.M.,Federal University of Lavras | Carvalho G.R.,Unidade Regional do Sul de Minas Uresm | de Rezende J.C.,Unidade Regional do Sul de Minas Uresm | Botelho C.E.,Unidade Regional do Sul de Minas Uresm | And 3 more authors.
Ciencia Rural | Year: 2014

The objective of this work was to evaluate the agronomic traits of coffee tree progenies. The experiment was set in Ouro Verde Farm, located at Campos Altos County, MG. Twenty three coffee progenies and seven control cultivars were used. These progenies are from the fourth generation of crossing between Timor Hybrid and Catuaí. The experiment was set in a randomized block design with four replicates, a total of 120 plots with 8 plants per plot. The yield of processed coffee sacks ha-1 was evaluated in eight crop years from the 2003 to the 2011 harvests. The percentage of fruits at the cherry stage, floating fruits, coffee classification (sieve above 17), income and plant vigor were evaluated in the 2010 and in the 2011 harvests. It was concluded that the progenies showed a great variability for the agronomic traits. Progenies 514-7-4- C130, 493-1-2-C134 and 518-2-10-C408 had the highest yield in the four two-year periods. The progenies 436-1-4-C26, 516-8-2- C109, 493-1-2-C134, 518-2-10-C408, 514-7-16-C211 and 514-7- 16-C208 presented the highest values for plant vigor. Progeny 493- 1-2-C134 stood out in all analyzed traits, showing to be promising for the advance of the generations. Source

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