Degenerescence of virus-free garlic cultivars in altitude conditions in the Semiarid region of the Northeast of Brazil

ABSTRACT It is necessary to use virus-free garlic seeds to reach high bulb yields; however, information is needed on the number of generations that these seeds can be grown in field conditions without decreasing bulb yield and quality due to degeneration. Degeneration is dependent on the production season and locality; thus, the objective of this work was to evaluate the degeneration of virus-free garlic cultivars grown in the Semiarid region of the Northeast of Brazil, through three experiments conducted in Portalegre, state of Rio Grande do Norte. Virus-free garlic cultivars were used in the first generation (G1) and second-generation (G2) and cultivars without clonal cleaning (infected) in the third experiment. The experiments were conducted in randomized blocks experimental design, with four replications. The treatments consisted of five cultivars: Amarante, Branco Mossoró, Cateto Roxo, Gravatá, and Hozan. The use of G2 garlic seeds in field conditions is viable, mainly for the cultivars Branco Mossoró and Hozan, which showed lower production losses. However, further evaluations, considering at least four generations, are necessary for these cultivars, since the degeneration level depends on the crop environment.