EFFECT OF SOPONINS AND ALKALOIDS ON STINK BUGS CONTROL AND YIELD OF COMMON BEAN VARIETIES (Phaseolus vulgaris L.)

Stink bugs cause damage to a wide variety of agricultural crops worldwide, resulting in significant yield losses. The study aimed to evaluate the level of damage caused by stink bugs to common beans and to determine whether the presence of saponins and alkaloids in the legumes of various common bean varieties contributes to reducing the damage and yield losses caused by the stink bug complex in this crop. During the three planting seasons evaluated, five species of stink bugs were identified in common bean, with Nezara viridula being the most prevalent (41.07% of the total), followed by Chinavia rolstoni and Chinavia marginatum, with 21.84 and 18.16%, respectively. White-seeded varieties exhibited the highest susceptibility to stink bug incidence, with BAT-482 being significantly affected. The phytochemical screening revealed the presence of saponins and alkaloids in all bean varieties with higher levels in black-seeded varieties, reaching 30 and 161 mg/mL, respectively. The BAT-482 (white seed coat) variety exhibited the highest yield losses, ranging from 0.31 to 0.45 t/ha, with significant differences compared to the other common bean varieties, except for Velasco Largo (red seed coat). Black-seeded varieties recorded lower losses. These findings highlight the impact of stink bugs on common bean crops and the role of bean variety in susceptibility and chemical composition, which ultimately influence yield losses.