Estimation of Yield Losses of Three Corn Varieties Due to Stem Borers Sesamia cretica Led. and Ostrinia nubilalis(Hb.) in El- Bostan Region, El-Behiera Governorate

Abstract

This study aimed to assess the yield losses in three varieties of maize (white, yellow and sugary corn) due to stem borers; Sesamia critica and Ostrinia nubilalis under field conditions and insecticide treatment. The yield losses was conducted using the conventional and analytical methods to compare whichever more accurate.The analyzed results of the present study shows that the grain weight/ear of intact maize were significantly influenced by the corn variety, while, it wasn't affected by insecticide treatment. The highest grain weight was obtained in white corn 154.33 gm/ear, on the contrary, the sugary corn recorded the lowest grain weight (36 gm/ear). The means of grain weight / ear were clearly decreased under stem borers, S. creticae and O. nubilalis infestation, with a higher susceptibility for the white corn.Under insecticidal treatment, the yield losses due to S. cretica, and O. nubilalis were reduced by 44.26% and 60.87% in white corn, and by 8% and 41.27% in yellow corn, respectively. The yield losses due to plant absence were, 3.75, 4.8 and 10.53% for white, yellow and sugary corn, respectively.The present results indicate that the analytical method was more accurate than the conventional method, whereas, analytical method put in consideration yield loss from absent plants during assessment of yield losses.

Isolation and pathogenicity of endophytic fungi associated with some maize hybrids against certain Lepidoptera pests

“…Therefore, EEF presents a substantial alternative to the application of either fungal or chemical insecticides and genetically modified plants, since they could grant their host plants with systemic and long term protection against pests (Yang, 2015;Bamisile et al, 2018 a & b;Bubica Bustos et al, 2020). In Egypt, maize is an economically indispensable crop grown for domestic consumption (Al-Eryan et al, 2019). One of the most important pests that threaten maize crop in Egypt is the stem borer, Sesamia cretica, which attack the plant during seedlings stage, however, due to their vulnerability, maize seedlings attacked by this pest could be destroyed (El-Husseini et al, 2018;Al-Eryan et al, 2019).…”

“…In Egypt, maize is an economically indispensable crop grown for domestic consumption (Al-Eryan et al, 2019). One of the most important pests that threaten maize crop in Egypt is the stem borer, Sesamia cretica, which attack the plant during seedlings stage, however, due to their vulnerability, maize seedlings attacked by this pest could be destroyed (El-Husseini et al, 2018;Al-Eryan et al, 2019). Many endophytic entomopathogenic fungi have potential pathogenic effects against the maize lepidopterous and price sucking insect pests and also promote plant growth and yield (Mahmood et al, 2019 and.…”