Caracterização do clone 'Prata-Anã' Gorutuba no Norte de Minas Gerais

Abstract

This work aimed to evaluate the genetic and phenotypical differences between clones of banana ‘Prata Anã’ Gorutuba and cultivate common ‘Prata Anã’ from the Banana Active Germplasm Bank (BAGB) of Embrapa Cassava and Tropical Fruits, through RAPD molecular markers and morphologic describers and characterize these banana ‘Prata Anã’ Gorutuba clones as to the reaction to different isolates of Fusarium oxysporum Schlecht.: f.sp. cubense (Foc). Five properties were chosen in North of Minas Gerais, which grow ‘Prata Anã’ Gorutuba. Morphologic characterization was done through quality evaluation of 74 describers: of the plant, the bunch and the inflorescence. Among the 74 describers morphologic evaluated on the 21 ‘Prata Anã’ clones, 53 presented the same class, being homogeneous for all the clones. As to the characteristics of the plant, the green tone of the pseudostem (TCV), presence of anthocyanin (ANT) in the pseudostem, shape of bunch (FCA) and flexion of the banana hands (FLX) varied among clones of ‘Prata Anã’ Gorutuba, common ‘Prata Anã’ and ‘Prata Anã’ Catarina. The genetic distance among the clones and group analysis was calculated. The 14 RAPD initiators produced a total of 116 bands, being 56 monomorphic bands and 60 polymorphic. The primers OPP 14, OPB 10, OPG 17, OPE 12 and OPU 10 generated the larger number of polymorphic bands. The biggest amount of dissimilarities was obtained between the PGFS 7 and PGFU 4 (15,36%). Grouping the clones by place of collect or origin was not possible. To determine the behavior of ‘Prata Anã’ clones on different isolates of Foc in greenhouse conditions was used a completely randomized design under 4 x 5 factorial, with three varieties of banana (common ‘Prata Anã’, ‘Grand Naine’ and ‘Maçã’) and the clone of ‘Prata Anã’ Gorutuba and four isolates of Foc, represented by the isolated 106, 132, 150 and a mix of several isolated (mix of 10 isolates) and the control (cornmeal substrate). Each treatment was made of 10 repetitions. There were evaluations every 20 days in order to establish the growth of the plants. 120 days after planted, the disease was evaluated on the rhizome. The ‘Prata Anã’ Gorutuba clone presented itself to be statistically equal to ‘Grand Naine’ cultivar in presence of isolates 150 and 132, and although having presented similar behavior to common ‘Prata Anã’ in the presence of isolated 106 The ‘Prata Anã’ Gorutuba was superior to cultivar ‘Maçã’ in the presence of the three most aggressive isolates used (150, 106 and isolated mixes). It was observed that the levels of severity on ‘Prata Anã’ Gorutuba clone and common ‘Prata Anã’ and ‘Maçã’ cultivars varies according to the presence of the different isolates, and the most aggressive one were 106 and isolates mix. Common ‘Prata Anã’ presented equal severity levels on every isolate, except the mix. The conclusion was ‘Prata Anã’ Gorutuba clones are resistant to isolates 150 and mix of Foc and susceptible to isolate 106. Isolate 106 is highly aggressive to ‘Maçã’ cultivar. Among the isolates used, 132 was, in average, less aggressive to common ‘Prata Anã’ and ‘Maçã’ and did not present aggressively to clones of ‘Prata Anã’ Gorutuba.