La coltivazione del riso in regime biologico: i risultati della sperimentazione 2012-2013

Within the frame of a national project on organic farming, evaluation of rice varieties under organic farming conditions was carried out during years 2012 and 2013. Selected varieties included recently developed and traditional ones belonging to all different merceological classes. For the round rice group, the varieties were Brio, Cerere, Ducato and Selenio. For the long A group, varieties were chosen according to their end use: Loto and Opale, utilized for the production of parboiled rice while Ulisse, Meco and Volano for the national market. For the long B group, Arsenal, Ellebi and Salvo were tested. The experimentation revealed an average yield of about 6 t/ha in 2012. In the 2013, satisfactory yield were obtained in the Mede trials (about 6,4 t/ha), while in the trials of Cascine Strà the varieties recorded average yield slightly higher than 3,2 t/ha, indicating that restriction in management under organic farming may cause unsatisfactory yield values. In the two years of trials, all the round rice varieties (Brio, Cerere, Selenio e Ducato) allowed high yield of wholly milled rice, confirming the good performances of this merceological class in organic farming, while for the long A group, Loto, Meco and Opale were the best performing for this parameter in the two years. Considering production yield and yield of wholly milled rice in the two years, the results therefore showed that round rices (Brio, Cerere, Selenio e Ducato) provide the better results. Within the long A for parboiling, Loto confirmed its reliability in the two years and in the different locations. It was instead more complicated to identify other varieties with good performances since good results obtained in one year were frequently not confirmed in the second year. However, in the first year the varieties Meco (long A for the national market), Salvo and Arsenal (long B), while in the second year the variety Ulisse (long A for the national market) demonstrated good adaptability in at least two field trials locations.