Juliana Costa de Rezende

Micropropagação do abacaxizeiro ornamental

ABSTRACT Protocol for in vitro micropropagation of ornamentalpineapple The Ananas comosus var. erectifolius is an ornamental pineapplecultivar which greatly interests Brazilians and foreign landscapersand flower producers for being an exotic and rustic tropicalornamental plant. The market demand for high quality of cuttingsrequires efficient methods of propagation and in this context thetissue culture stands out as a viable alternative to obtain plants withgenetic and phytossanitary quality in a short time. In the presentwork we studied the influence of concentrations of BAP (0; 0.5; 1.0;1.5 mg L -1 ) and NAA (0; 0.12; 0.24; 0.48 mg L ) in the MS mediumculture within 0; 2.5; 5.0; 7.5 g L -1 of agar, in order to establish an invitro protocol for multiplication and rooting of ornamental pineapple.Plantlets with 1.5±0.5 cm already established in vitro , extracted frombuds of ornamental pineapple fruits crown were inoculated asepticallyin flasks. After inoculation the plantlets were kept in a growth roomat 26±1

Adaptabilidade e estabilidade fenotípica de cultivares de café arábica em Minas Gerais

The objective of this work was to evaluate the phenotypic adaptability and stability for grain yield of the Catuai group of coffee cultivars by the method Annicchiarico. The experiments were installed and carried out in the counties of Tres Pontas, Campos Altos and Capelinha, Minas Gerais state, Brazil. The experiments were carried out in a randomized complete block design, with four replicates and six plants per plot. The treatments were constituted by 15 cultivars of the Catuai group and five controls. The grain yield evaluations were performed in the six harvests from 2003/2004 to 2008/2009 growing seasons. Then, the joint analysis of the three localities and the evaluation of cultivars adaptability and stability were performed. The parameters floating beans and high sieve grains were carried out considering the 2008/2009 harvest. The cultivars Catuai Vermelho IAC 15, Catuai Amarelo IAC 30, Catuai Amarelo IAC 62 and Catuai Vermelho IAC 72 were the most promising because they allied higher stability and adaptability in favorable and unfavorable environments with mean high yield. The cultivars Catuai Vermelho IAC 100, Catuai Amarelo IAC 86, Rubi MG 1192 and Catuai Vermelho IAC 144 have the highest percentage of bean size grains. All the cultivars showed low percentage of floating grains.

Desempenho agronômico de cultivares de café resistentes à ferrugem no estado de Minas Gerais, Brasil

The purpose of this study was to evaluate the agronomic performance of 24 coffee cultivars (22 rust resistant cultivars and 2 susceptible control varieties) in different environments of Minas Gerais State, Brazil. The coffee plants were planted in four locations (Lavras, Campos Altos, Patrocinio and Turmalina) in three agroclimatic regions. The experiments were arranged in randomized complete block design, with three replications in plots measuring 3.5x0.7 m, with 10 plants per plot. The following traits were analyzed: yield, percentage of grains retained in sieve size 16 and vegetative vigor from four cropping years (2008 to 2012) and the adaptability and stability in yield. The cultivars showed differential performance in the four environments. The cultivars Sabia Tardio, Pau Brasil MG1, Obata IAC 1669-20, Catucai Amarelo 24/137 and IPR 103 were the most promising because they combined higher agronomic stability and adaptability in favorable and unfavorable environments.

Prediction of genetic gains from selection in Arabica coffee progenies

Gains from selection for yield were estimated in Arabica coffee progenies carrying rust-resistance genes. The experiment in augmented block design was installed in Tres Pontas, state of Minas Gerais. Three blocks were established with six plants per plot, spaced 3.50 x 0.90 m, in 96 regular (F2 progenies) and two control treatments. The plant response to rust was evaluated on a grade scale in 2008. Yield (bags per hectare) was estimated in the growing seasons 2005 to 2008. Significant differences between treatments for yield were observed in all harvests, except 2005. The presence of genetic variability among progenies allowed significant gain from selection for yield. Under the experimental conditions of this study, selection for yield can be performed in the first high-yield year, without major losses compared to genetic gain from selection for yield when based on the mean of four harvests.

Fontes de nitrogênio, polpa de banana e ágar no desenvolvimento in vitro de plântulas de orquídea

Foram realizados dois experimentos com o objetivo de estudar os efeitos de fontes de nitrogenio, polpa de banana e agar no desenvolvimento in vitro de orquidea Cattleya loddigesii. O primeiro experimento constituiu-se de NH4NO3 (0; 25; 50; 75 e 100% da formulacao de 330 mg L-1) e KNO3 (0; 25; 50 e 100% da formulacao de 380 mg L-1) acrescidas ao meio MS. No segundo experimento, os tratamentos consistiram de concentracoes de agar (0; 2; 4; 6 e 8 g L-1), no meio de cultura Knudson C, acrescido de polpa de banana nanica (0; 50; 100; 150 e 200 g L-1) em todas as combinacoes possiveis. Apos a inoculacao as culturas foram mantidas em sala de crescimento com irradiância em torno de 35 μmol m-2 s-1, temperatura de 25±1oC e fotoperiodo de 16 horas, por 90 dias. Com base no peso da materia fresca das plântulas, numero de raizes, comprimento da parte aerea e comprimento da maior raiz, a adicao de 17,5 a 41,16% da formulacao original de NH4NO3 ao meio MS proporcionou melhor desenvolvimento in vitro em plântulas de Cattleya loddigesii. Maior numero de folhas foi obtido com a adicao ao meio MS de 100% da formulacao original de NH4NO3 e 50% de KNO3. A multiplicacao in vitro de plântulas de orquidea Cattleya loddigesii e viavel em meio Knudson C liquido com a utilizacao de 128,42 g L-1 de polpa de banana nanica.

Divergência genética entre cafeeiros do germoplasma Maragogipe

This study aimed to identify the genetic divergence among coffee trees of the Maragogipe group in the active germplasm coffee bank in Patrocinio, Minas Gerais, Brazil, using multivariate analyzes. In the study, 27 morpho-agronomical descriptors were assessed. Mahalanobis generalized distance was applied to quantify the genetic divergence among genotypes. The following methods were used: Tocher clustering, Unweighted Pair-Group Method Using Arithmetic Averages (UPGMA) hierarchical clustering and the canonical variables analysis. The cluster analysis by Tocher method and the UPGMA separated the accessions into three and six groups, respectively. The analysis of the relative contribution of each characteristic to the genetic dissimilarity highlighted the intensity of curling leaf, inflorescence number per leaf axil and average yield as those that contributed most to the achievement of genetic divergence. It was observed that the first three canonical variables explained more than 90% of the total variance contained in the set of the analyzed characteristics. The combination between MG0167 and MG0170 accessions is the most promising for a possible crossing for immediate use in breeding programs.

Desempenho agronômico de seleções de café Bourbon Vermelho e Bourbon Amarelo de diferentes origens

O objetivo deste trabalho foi avaliar a adaptabilidade e estabilidade fenotipica e outras caracteristicas de interesse agronomico de genotipos de cafe Bourbon Vermelho e Bourbon Amarelo, para selecionar os de melhor desempenho no Estado de Minas Gerais. Foram avaliados 17 genotipos pertencentes ao grupo Bourbon, bem pontuados em concursos de qualidade de bebida, alem de tres cultivares amplamente cultivadas no estado, utilizadas como testemunhas. Os experimentos foram instalados em dezembro de 2005, nos municipios de Lavras, Santo Antonio do Amparo, Tres Pontas, Campos Altos e Patrocinio. As avaliacoes foram realizadas durante as quatro primeiras colheitas, nos anos agricolas 2007/2008, 2008/2009, 2009/2010 e 2010/2011, e compreenderam as seguintes caracteristicas: produtividade de graos, adaptabilidade e estabilidade fenotipica, percentagem de frutos chochos, vigor vegetativo e classificacao por peneira. Ha variabilidade genetica dentro do grupo de Bourbon estudado. Os genotipos de Bourbon apresentam produtividades satisfatorias em todos os locais avaliados. O genotipo Bourbon Vermelho 2 apresenta maior adaptabilidade, tendo-se destacado quanto a todas as caracteristicas avaliadas.

Eficiência na seleção de progênies de cafeeiro avaliadas em Minas Gerais

The present work had the aim of verifying the selection efficiency of coffee plants originated from the crossing between Catuai and Icatu with Timor Hybrid. Eighteen progenies developed by the Program of Genetic Improvement of Epamig/UFLA/ UFV were evaluated. Coffee plants were planted in December 2005 in the following counties: Lavras, Campos Altos and Patrocinio, in the State of Minas Gerais. The characteristics analyzed were: productivity, grain size and proportion of cherry fruit. In order to verify the efficiency of the selection, the index of coincidence was applied according to the methodology of Hamblin and Zimmermann (1986), as well as the magnitude of the interaction progenies x environments and its decomposi - tion in simple and complex parts using the methodology of Cruz and Castoldi ( 1991). The predominance of the complex part in relation to the simple one in the interaction of the progenies x environments confirms the low or absence coincidence of the progenies in different environments, raising difficulties for a general recommendation for different coffee regions in the State of Minas Gerais.

Micropropagação do maracujazeiro-do-sono

Micropropagation of Passiflora setacea DC. Propagation of Passiflora setacea DC. is extremely difficult, therefore tissue culture techniques become a viable alternative. The objective of this study was to evaluate the in vitro germination and determine the best culture medium for micropropagation. This work was carried out in two stages; in the first, seeds were placed in ½ MS culture medium and 30 g L -1 of sucrose, distributed in tubes and supplemented with different AG 3 concentrations. The pH of culture medium was adjusted for 5.8 before adding 6.0 mg L -1 of agar. After seed inoculation, the cultures were kept in a growth room under 35 µmol.m -2 .s -1 , 26±1oC and photoperiod of 16 hours. Just after germination, the seedlings were transferred to tubes containing ½ MS, constituting a second experiment, in order to test culture media with different sucrose concentrations. The experiments were arranged in a complete randomized design, in a 3x3 factorial, with four repetitions and 15 seeds/plot (first experiment) and a 4x4 factorial, with four repetitions and 3 plants/plot (second experiment). The best results for micropropagation were obtanied in MSM medium with 28.51 and 28.74 g L -1 of sucrose. The highest germination speed index was obtained with 20 mg L -1 of AG 3 combined with seed tip scarification.

Agronomic traits of coffee tree progenies from Timor Hybrid x Catuaí crossing

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 Catuai. 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.