Variabilidade de Fusarium oxysporum F. lycopersici (Wr) Sny & Hans em São Paulo

Abstract

A Murcha de Fusarium em tomateiro não está sendo eficientemente controlada no Estado de São Paulo, devido a falta de variedades resistentes, adequadas ao mercado. Como na produção destas, variedades resistentes é necessário um estudo sôbre a variabilidade do fango quanto a raças fisiológicas os autores pesquisaram 48 linhagens de Fusarium coletados em todo o Estado de São Paulo e através de testes em variedades diferenciais Bonny Best., Santa Cruz (Kobayashi) e S-34 em condições de casa de vegetação com contrôle parcial de temperatura e inoculaçôes artificiais. Concluiram que das 48 linhagens estudadas uma desta apresentava reação de raça 2 as demais 47 a da raça 1 sendo possível reparar as linhagens pelo gráu de patogenicidade.

A three–decade survey of Brazilian Fusarium oxysporum f. sp. lycopersici races assessed by pathogenicity tests on differential tomato accessions and by molecular markers

“…Most of the long‐shelf life hybrids available in the Brazilian market were resistant to both race 1 and race 2. Even though previous misleading reports indicated the presence of FOL race 3 in Brazil (Tokeshi and Galli 1966; Tokeshi et al . 1966; Tokeshi and Noguez 1974), the first official record of this tomato pathogen in the country was done in the early 2000s in long‐shelf life hybrids (harbouring the I and I –2 genes) in the States of Espírito Santo (Reis et al .…”

“…FOL is a seed‐transmissible pathogen and seeds (and often seedlings) of the major ‘Santa Cruz’ cultivars (both resistant and susceptible to race 2) were mainly produced in São Paulo State and then distributed throughout the country. In this scenario, two working hypotheses were proposed to explain the occurrence of race 2 in Brazil: (i) high frequency of mutation from race 1 to race 2 and (ii) this mutation occurred in the direction of increasing the virulence profile and aggressiveness of race 1 isolates previously existing across the Brazilian tomato–producing regions (Tokeshi and Galli 1966). Our analysis using the race‐specific molecular marker system developed by Hirano and Arie (2006) with Brazilian race 2 isolates displaying typical amplicon profile of the cosmopolitan race 1 isolates gives support to both hypotheses.…”

Multifaceted intervention of Bacillus spp. against salinity stress and Fusarium wilt in tomato

“…On this test, all pots, except for the control, received weekly rate of 5 ml (1 9 10 8 CFU per ml) of the corresponding Bacillus strain per plant. The external disease severity was evaluated weekly according to the following scale adapted from Tokeshi and Galli (1966): (i) healthy plant; (ii) plant with yellowing until the second leaf; (iii) plant with yellowing up to the third leaf; (iv) plant with wilt and without yellowing; (v) plant with wilt and yellowing; and (vi) dead plant. With the external symptoms data, the area under the disease progress curve (AUDPC) was calculated (Shaner and Finney 1977).…”

Biochar amendment increases soil microbial biomass and plant growth and suppresses Fusarium wilt in tomato

“…The external disease severity was evaluated weekly according to the following scale adapted from Tokeshi and Galli (1966): 1, healthy plant; 2, plant with yellowing until the second leaf; 3, plant with yellowing up to the third leaf; 4, plant with wilt and without yellowing; 5, plant with wilt and yellowing; and 6, dead plant. With the external symptoms data, the area under the disease progress curve (AUDPC) was calculated (Shaner and Finney 1977).…”