03396naa a2200301 a 450000100080000000500110000800800410001902200140006010000210007424501940009526000090028952024620029865000180276065000200277865000210279865000110281965300190283065300270284970000180287670000210289470000210291570000160293670000170295270000170296970000230298670000200300977300650302920028242023-05-26       2014    bl uuuu     u00u1 u    #d  a1835-27071 aARAUJO, A. G. de  aHost-pathogen interactions of Musa spp. and Mycosphaerella musicola with epidemiological variables and leaf anatomy within the pathosystem of Yellow Sigatoka disease.h[electronic resource]  c2014  aYellow Sigatoka, which is caused by Mycosphaerella musicola/Pseudocercospora musae, is the primary biotic problem for the Brazilian banana crop, with the causal agent presenting high pathogenic variability among the pathogen isolates. Few details concerning the host-pathogen interactions that occur during the infection process are available for this disease. Studies have been carried out under greenhouse conditions with artificial inoculation with 2 M. musicola isolates (1 - Lavras, Minas Gerais state and 2 - Cruz das Almas, Bahia state) of a group of banana varieties, including 'Grand Naine', 'Prata Ana', 'Calipso', 'Preciosa', 'Japira' and 'BRS Platina'. In each plant, two leaves were inoculated; F1 - Leaf number one and F2 - Leaf number two. After the dynamics of host-pathogen interactions, the different bananas genotypes were evaluated and the fungus-associated changes in the leaf anatomy within the tissues and stomata were determined. Inoculations were carried out with a suspension of 4.104 conidia/mL that was sprayed onto micropropagated plants of the different genotypes. The lower limb surface of the number one leaves (F1) and number two leaves (F2) was sprayed until runoff. The data were collected weekly over ten weeks, although shorter incubation and latent periods were observed in the susceptible varieties (Grand Naine and Prata Ana). The Grand Naine genotype showed the greatest disease severity, confirming its susceptibility to yellow Sigatoka. The leaf inoculation of M. musicola altered the anatomy. In most cases, contamination increases the thickness of the epidermis, hypodermis and parenchyma. However, the thickness of leaf tissues was reduced in Prata Ana. The BRS Platina hybrid showed the greatest variation in these parameters. In general, infection with Mycosphaerella significantly decreased the stomatal density. Exceptions to this behavior occurred in the epidermis of the leaves of Grand Naine and BRS Platina. The resistant genotypes, Preciosa, Japira and BRS Platina, are promising for commercial plantations in regions where the yellow Sigatoka inoculum pressure is high. The isolate from Cruz das Almas, Bahia State, was more pathogenic (AUDSPC=7.9100) than was the one from Lavras, Minas Gerais State (AUDSPC=3.2737), in which the Grand Naine susceptible genotype was inoculated. Yellow Sigatoka infection changed the leaf anatomy by altering the leaf thickness and the number and size of the stomata.  aPlant anatomy  ayellow Sigatoka  aAnatomia vegetal  aBanana  aPlant diseases  aProgress curve disease1 aVAL, A. D. B.1 aSOARES, J. D. R.1 aRODRIGUES, F. A.1 aPASQUAL, M.1 aROCHA, H. S.1 aASMAR, S. A.1 aCORDEIRO, Z. J. M.1 aSILVA, S. de O.  tAustralian Journal of Crop Sciencegv. 8, issue 8, Aug 2014.