EFFECT OF THE PARASITE PLANT Lennoa madresporoides Lex. ON SUNFLOWER CROP IN THE STATE OF GUANAJUATO, MEXICO.

In the state of Guanajuato in Mexico, from 2016 to 2024, the planting of high oleic sunflower has been promoted, mainly under rainfed and irrigated conditions.During the spring-summer cycle of 2024, it was reported in four commercial lots of high oleic sunflower, which were in the flowering stage to grain filling, but with drying of the entire distributed in patches of up to almost a quarter of a hectare in the producer's plot.The location of these plots was in the municipalities of Pueblo Nuevo and Dolores Hidalgo, both located in the state of Guanajuato, Mexico.The objective of the research was: 1) to identify the cause of plant drying at the flowering stage and during grain filling; 2) to determine the incidence and degree of severity on sunflower yield in the affected plots in both municipalities.Results in both municipalities, the most affected lot was sampled to detect and identify the cause of the drying of the plant, it was corroborated that the plant attached to the sunflower root is the parasitic plant known as "ground flower" Lennoa madresporoides belonging to the Lennoaceae family.Regarding incidence, the average percentage was 74.8% and 80.8% in the municipalities of Pueblo Nuevo and Dolores Hidalgo, and the percentage of severity in yield reduction was 90% and 91%, respectively, in both municipalities.