Acessibilidade / Reportar erro

Bioactivity ofresistance inductors in the management of guava (Psidium guajava L.) anthracnose

ABSTRACT

The culture of guava present losses around 40-60% in postharvest related to phytosanitary problems such as anthracnose caused by Colletotrichum gloeosporioides. Research on alternative methods using resistance inductors have been quite promising in the search for products with high potential in the control of pathogens in postharvest. The present study aimed to evaluate the resistance inducers in controlling anthracnose and its effects on physical and chemical quality in fruits of guava ‘Paluma’. The treatments were: Agro-mós®, Ecolife®, Fosfitonova K®, Cuprogarb 500®, Rocksil® and witness (distilled water and sterile). The in vitro test with C. gloeosporioides colony discs (0,45 cm diameter) with seven days of culture and put into PDA culture medium added with elicitors. It was determined the percentage of inhibition of mycelial growth of C. gloeosporioides. And the in vivo test was conducted with fruit variety of guava Paluma, disinfected and treated with elicitors then C. gloeosporioides colony discs were inoculated and the first to the eighth day, evaluations were made of lesions diameter in the fruit sand was also performed post-harvest analysis, assessing the loss of fresh mass, total soluble solids (TSS), titratable acidity (TA), reason TSS/TA and hydrogenic potential (pH). It was used a completely randomized design in a split plot design 6x8 (treatments x evaluation period) and the averages compared by Tukey test at 5% probability. The elicitors Agro-mos®, Ecolife®, Fosfitonova K®, Cuprogarb 500® and Rocksil® inhibited the mycelial growth of C. gloeosporioides in vitro, reduces the lesions diameter and maintained post-harvest quality fruit guava ‘Paluma’.

Keywords
Colletotrichum gloeosporioides; Guava; Induction of resistance; fungitoxic substances

Grupo Paulista de Fitopatologia FCA/UNESP - Depto. De Produção Vegetal, Caixa Postal 237, 18603-970 - Botucatu, SP Brasil, Tel.: (55 14) 3811 7262, Fax: (55 14) 3811 7206 - Botucatu - SP - Brazil
E-mail: summa.phyto@gmail.com