Fusarium equiseti as One of the Main Fusarium Species Causing Wilt and Root Rot of Chickpeas in Morocco

Abstract

Fungal isolates of Fusarium were collected from symptomatic chickpea (Cicer arietinum L.)  plants growing in fields within Souk Tlat commune in the Gharb region. Morphological and molecular characterizations were performed of the fungal isolate N3 obtained from a chickpea plant. PCR amplification and sequencing of the internal transcribed spacer using the primers ITS1 and ITS4 was applied to identify the fungal isolate N3. The maximum similarity index of the fungus was found to be 99.33% with Fusarium equiseti (accession no. MT111122). In the pathogenicity test, both chickpea seed dip inoculation and soil infestation by the spore suspension of Fusarium isolate were adopted. Four weeks after chickpea seed inoculation, few plants emerged and those that emerged were stunted. A high percentage of inoculated seeds did not emerge and showed accentuated rot symptoms. Eight weeks after sowing seeds in infested soil, the obtained chickpea seedlings displayed root necrosis, browning at the crown, and wilting. In addition, these plants showed a foliar alteration index of 0.395. The re-isolation was positive for different parts of chickpea plants for both seed and soil inoculation. Fusarium equiseti isolate decreased the length of the root and aerial parts, and number of leaves and branches of the inoculated chickpea plants either by seed inoculation or soil infestation with values of 0.91 cm and 19.73 cm, 1.29 cm and 19.44 cm, 1.11 and 18.66, and 0.0 and 2.08 respectively, whereas the corresponding values for the control plants were 27.16 and 28.33 cm, 29.05 and 31.05 cm, 24.21 and 25.66, and 3.50 and 3.11, respectively. To the best of our knowledge, this is the first report of F. equiseti on chickpea (Cicer arietinum L.) in Morocco.