Performance of some new soybean genotypes against the infestation of the cotton leaf worm, Spodoptera littoralis Boisd

Cotton leaf worm, Spodoptera littoralis (Lepidoptra: Noctuidae) is considered one of the most destructive insect pests in Egypt. A field trail was conducted at the experimental farm of Nubaria agricultural research station, Behaira Governorate, Egypt, during 2021 and 2022 seasons to evaluate the performance of 14 new genotypes and two check varieties under the cotton leaf worn natural infestation conditions. The experimental design was a randomized complete block design (RCBD) with three replicates. The combined results revealed that there were substantial differences across genotypes for all evaluated parameters. The genotypes (H7L39/2015, H6L49, and H6L28) were considered as more resistant ones over the resistant check variety (Giza 111) which recorded the least infestation (25.86, 27.57 and 32.14 %, respectively), with feeding damage area of 18.52, 19.58 and 18.58 %, respectively. These genotypes gave the highest leaf content of P%, K%, total phenolic compounds, yield, and its components. The correlations between infestation% and leaflet area damage% or N all were positive on one another. All other correlations, with the exception of plant height and branches no plant-1, had negative effects on one another. The results proposed that the genotypes (H7L39/2015, H6L49 and H6L28) are promising and could be planted at Nubaria region and used in the breeding programs.