Weed interference in melon crop under semi-arid conditions

The management of weeds in melon is hindered by the slow initial growth of the crop, favouring weed infestation and reducing production. During the years 2016 and 2017, weed interference periods were evaluated in two melon hybrids, yellow and frog skin, to determine the time of weed control in the crop. Four-parameter logistic regression was used to determine the critical weed control period (CPWC). The weed species with the highest occurrences in 2016 were Merremia aegyptia, Senna obtusifolia, and Urochloa plantaginea. In 2017, there was a predominance of M. aegyptia, indicating the possibility of successive cultivation, favouring the predominance of species with growth habits similar to melons. The increase in the period of living with weeds reduced the productivity and quality of melon fruits. Coexistence with weeds throughout the cycle reduced productivity by about 50%. The CPWC was 15 to 58 and 10 to 45 for frog skin and 12 to 52 and 4 to 50 days for yellow melon in 2016 and 2017, respectively, considering a productivity loss of 5%. These results underscore the importance of adopting strategies that allow melons to grow free from the presence of weeds, especially before they are fully established in the growing area.