Evaluation of commercial chickpea cultivars against Ascochyta rabiei in Argentina

PASTOR SILVINA; PUGLIESE BRUNO; VALETTI LUCIO; CROCIARA CLARA; FEKETE, ANA

modalidad virtual

Congreso; 5to Congreso Argentino de Fitopatología y 59na Reunión de la División Caribe de la APS; 2022

Asociacion Argentina de Fitopatologos y APS Caribean division

Ascochyta blight (Ascochyta rabiei)is the most important sanitary limitation of chickpea. It is a polycyclic disease that requires 15?25°C and 65?100% RH for infection and development. This pathogen has a great dispersal capacity, can survive within the infected crop debris for 3?4 years, and is seed transmitted. The genetic strategy is the most economic and environment-friendly for its proper management. The main varieties grown in Argentina are chañaritos S-156, norteño, felipe UNC-INTA and kiara UNC-INTA. The objective was to evaluate the behavior of these against A. rabiei. Seeds of all varieties were sterilized and incubated in humid chambers for 5 days at 21°C and 12h photoperiod. Twenty seedlings per variety were placed in 360 cm3 pots and kept in the greenhouse at 21°C and natural photoperiod, in a random block design. The plant inoculations were at V3-V4 using a suspension of A. rabiei conidia (1 × 105/ml) and they were maintained for 48 h at 100% RH and 65% RH for the following 12 days. Disease severity was evaluated 14 days post-inoculation, using a 1-9 categorical scale. Average readings per variety allowed to classify them as 1 asymptomatic; 1.1-3 resistant; 3.1-5 moderately resistant; 5.1-7 susceptible; 7.1-9 highly susceptible. The results were analyzed by Duncan?s test. All cultivars were susceptible, but chañaritos (mean 5.71) was significantly less susceptible of all. This is the first comparative study of chickpea varieties against A. rabiei in Argentina