Stability in cassava (<em>Manihot esculenta</em> Crantz) cultivar yield in Paraná State

Abstract

The present study was carried out to quantify the genotype x environment interaction of nine cassava cultivars and to estimate the phenotypic stability parameter by Plaisted and Peterson (1959) and Kang (1988) methodologies, in the cities of Maringá and Rolândia, located in the state of Paraná, southern Brazil, during the agricultural years of 1995/96, 1996/97 and 1997/98. The treatments were in complete, randomized blocks, with four replications. The Plaisted and Peterson method showed the IAC 169-86, IAC 47-86 and Branca de Santa Catarina cultivars to be the most stable. The IAC 169-86 and IAC 47-86 cultivars presented the lower ranks total, and therefore were considered the most stable and productive by Kang method (1988). The IAC 169-86 cultivar was a stable and productive material, resistant to bacteriosis, with average susceptibility to overlengthening, being, thus, eligible for recommendation to cassava producers in northern and northwestern Paraná.