Natan Ramos Cavalcante

Associações entre características vegetativas e de produção em progênies de irmãos completos de goiabeira

The objective of this work was to estimate the genetic parameters and to evaluate the associations between vegetative and yield characteristics, in full-sib progenies of guava tree (Psidium guajava). The following characteristics were evaluated: yield per plant, number of fruits, fruit mass, plant height, stem diameter, and canopy volume. The estimation of genetic parameters was obtained by the REML/Blup procedure. Based on the breeding values predicted by Blup, the genetic and canonical correlations were estimated, and the genetic correlation coefficients were unfolded into direct and indirect effects on the character yield per plant using path analysis. Genetic variability was estimated for number of fruits (567.66) and yield per plant (11.818), with high genetic correlation (0.9045), indicating simultaneous selection. Indirect selection did not promote simultaneous gains for yield per plant with the primary components number of fruits and fruit mass, making it difficult to obtain guava cultivars with high yield, number of fruits, and fruit mass. The vegetative traits had little effect on yield, number of fruits, and fruit mass.

PRODUCTIVITY, FRUIT PHYSICOCHEMICAL QUALITY AND DISTINCTIVENESS OF PASSION FRUIT POPULATIONS

A avaliacao da produtividade e da qualidade fisico-quimica apresenta importância, pois permite identificar populacoes superiores. Porem, para lancar material, e necessario seguir os descritores conforme as instrucoes para a execucao dos ensaios de DHE. Desta maneira, objetivou-se avaliar tres populacoes de maracujazeiro-azedo que apresentem caracteristicas de alta produtividade e qualidade fisico-quimica, para lancamento comercial. O experimento foi conduzido na area experimental da Universidade do Estado de Mato Grosso, situada no municipio de Tangara da Serra-MT. O delineamento experimental foi o de blocos completos casualizados, com quatro repeticoes e dez plantas por parcela. As caracteristicas fisico-quimicas foram submetidas a analise de variância e comparadas pelo teste de Tukey. Para avaliar a distinguibilidade, foram utilizados 25 descritores, onde os dados quantitativos foram convertidos em multicategoricos, visando a obter matriz de dissimilaridade. A partir da matriz de dissimilaridade, formaram-se grupos pelo metodo de Tocher e UPGMA. A maior produtividade e o maior numero de frutos foram verificados na cultivar BRS Rubi do Cerrado e na populacao UNEMAT S10. As populacoes e as cultivares apresentaram caracteristicas fisico-quimicas que atendem as qualidades exigidas tanto para o mercado in natura como para a industria. Com base no ensaio de distincao entre genotipos, observou-se que os descritores foram eficientes para a diferenciacao das populacoes. A populacao UNEMAT S10 possui caracteristicas que a distinguem das demais cultivares e populacoes avaliadas, alem de possuir alto desempenho agronomico e, portanto, de poder ser lancada como cultivar comercial.

Associations among production and physicochemicalquality fruit traits in Passion fruit populations subjected to three cycles of intrapopulation recurrent selection

The present study was developed to identify the direct and indirect effects of fruit production traits in passion fruit on traits of agronomic interest as well as determine possible changes in associations between the characters after three cycles of recurrent selection. Twenty three half-sibling progenies were evaluated for the characteristics number of fruits per plant; fruit mass per plant (g); pulp percentage (%); fruit length and diameter (mm); peel thickness (mm); total soluble solids content (oBrix); pH; and yield per plant (kg). Fruit production per plant was considered the main variable, while the others were considered explanatory variables. Within-family heritability (h2ad) values were lower than the mean heritability of the progeny (h2mp). Path analysis revealed that the direct selection of genotypes with higher number of fruits or fruit average mass results in increased production per plant; however, indirect selection is inefficient in providing simultaneous gains. Therefore, by observing the correlations throughout selection cycles, it can be stated that although production per plant is the most important variable, preference should be given to the use of selection indices, as there are better chances of obtaining gains for fruit quality and production traits in selection across half-sibling passion fruit progenies.

HISTOLOGICAL ANALYSIS AND PERFORMANCE OF SOUR PASSION FRUIT POPULATIONS UNDER DIFFERENT ROOTSTOCKS RESISTANT TO Fusarium spp

The present study aimed to describe histological traits of the graft welding process and evaluate the effect of rootstocks on the physical and chemical traits and the productivity of sour passion fruit populations. The experiment was arranged in a randomized block design, in a 4x2 + 4 factorial scheme (cultivars / canopy x rootstocks), three replicates and nine plants per plot. Commercial cultivars and populations and Passiflora alata and P. nitida rootstocks, in addition to ungrafted plants were used as canopy. Cleft grafting was the grafting type adopted. Traits analyzed such as productivity and physical and chemical quality of fruits were submitted to analysis of variance and compared by the Tukey test. The canopy morphology was evaluated according to descriptors of the Ministry of Agriculture, Livestock and Supply. Grafting was carried out for each graft/rootstock combination for histological analysis. Sections were obtained by freehand cuts, stained and mounted on semi-permanent slides, examined under optical microscope and photomicrographed. Rootstocks affected the early cultivation and reduced productivity and number of fruits of passion fruit populations. Grafting did not affect the quality of fruits or the canopy morphology. Considering the complete culture cycle, P. alata species is able to be used as rootstock. The anatomical study demonstrates the occurrence of better compatibility in the connection of P. edulis tissues on P. alata, compared to grafting on P. nitida.