| Abstrakt: |
Two field experiments were conducted in Nubaria region, Behaira Governorate, Egypt, to investigate the influence of planting dates of maize crop on S. frugiperda infestation and assess both final yield and yield qualitative losses in 2022 and 2023 seasons. Results showed that S. frugiperda population increased with increasing the plant age and a highly significant S. frugiperda infestation reduces maize yields and causes yield quantitative losses. The three different planting dates (mid-April, mid-May, and mid-June) influenced the population of S. frugiperda throughout the two seasons. The mid-April plantation date achieved the lowest S. frugiperda population than the mid-May and mid-June plantation dates. The mid-June plantation achieved the annual highest average number with 15.97 and 18.89 larvae/25 plants, followed by the mid-May plantation with 11.75 and 15.36 larvae/25 plants in the first and second seasons, respectively with significant variations. However, in both seasons, the mid-April planting produced the annual least average numbers of 10.86 and 12.83 larvae/25 plants, respectively, in both seasons. The effects of maximum and minimum temperature and relative humidity differed from factor to factor and season to season. The mid-April plantation produced the highest yields 2.809 and 2.721 tons/fed with the lowest quantitative loss of 65.12 and 67.58%, followed by the mid-May plantation with yields of 2.797 and 2.548 tons/fed and quantitative loss of 65.12 and 67.58%, with significant differences in the first and second seasons, respectively. In addition, mid-June plantation gave yields of 2.511 and 2.469 tons/fed with the lowest quantitative losses of 80.41 and 81.85%. [ABSTRACT FROM AUTHOR] |
