In-vitro RESPONSE OF DIFFERENT FUNGICIDES AGAINST Mauginiella scaettae CAUSING DATE PALM INFLORESCENCE ROT IN TAFILALET OASIS IN MOROCCO

Abstract

The inflorescence rot is a very dangerous cryptogamic disease that is prevalent in all phoeniculture regions and causes heavy economic losses. The identification and characterization of the causal agent is a key step to tackling this disease, and such studies are very scanty in Morocco. This work was carried out in Darâa Tafilalet region South-East Morocco during 2020-2021 to isolate and identify the fungi that cause inflorescence rot on date palm and to try to combat the disease with various fungicides. We collected 48 infected samples from different varieties of date palm. The isolation results revealed that Mauginiella scaettae is the primary causal agent of date palm inflorescence rot at all sites investigated. In terms of in vitro experiments, we examined seven fungicides (difenoconazole, boscalid-pyraclostrobin combination, thiophanate-methyl, copper oxychloride, tribasic copper sulfate, copper sulfate, and wettable sulfur) based on their antifungal activity against the causal agent, M. scaettae. Data on the effects of these fungicides on pathogen mycelial growth, spore germination, and sporulation show that difenoconazole, the combination Boscalid-Pyraclostrobin, and Thiophanate-methyl totally controlled M. scaettae at only 25% of the recommended dose, whereas Copper Oxychloride, Tribasic Copper Sulfate, and Copper Sulfate had a significant inhibitory effect on all three stages. Wettable sulfur was the least effective.