ABSTRACT
Resistance reaction of soybean genotypes to Spodoptera litura under free-choice and no-choice tests and selection based on multiple traits

Ayda Krisnawati1, Zuyasna Zuyasna2, Rudy Soehendi1, Yuliantoro Baliadi1, Nuryati Nuryati1, and M. Muchlish Adie1*
 
Armyworm (Spodoptera litura) is the main leaf-damaging pest of soybean (Glycine max (L.) Merr.) plants. The research aims to assess the resistance response of soybean advanced lines against S. litura, evaluate their agronomic performance, and select the best genotypes based on multiple traits. The research was conducted in Malang, Indonesia. The evaluation for armyworm resistance was based on the free-choice test (FCT) and no-choice test (NCT). Each study utilized a randomized complete block design with 38 soybean genotypes and four replicates. The results showed that the NCT exerted a higher intensity of leaf damage and greater insect pest pressure compared to the FCT. Two soybean genotypes (G17 and G19) consistently demonstrated resistance to S. litura in both the FCT and NCT. Soybean seed yield has a significant positive correlation with plant height, number of filled pods, number of nodes, and number of branches, thus those characters could be used as indirect selection criteria for soybean yield. The selection based on GT Biplot revealed that G38 (resistant-control variety) and G17 had the best performance for resistance to S. litura, but did not exhibit significantly high seed yield. In contrast, G16 exhibited high yield performance but susceptibility to S. litura. The G36 was the best performer for the number of filled pods, number of nodes, number of branches, plant height, and 100-seed weight, despite being relatively less resistant to S. litura. G17 and G19 are promising candidates for breeding programs aimed at developing high-yielding and armyworm-resistant soybean varieties.
Keywords: Agronomic character, correlation, genotype-by-trait biplot, seed yield, selection, soybean.
1Research Center for Food Crops, Research Organization for Agriculture and Food, National Research and Innovation Agency, Jl. Raya Jakarta-Bogor 16911, West Java, Indonesia.
2University of Syiah Kuala, Faculty of Agriculture, Kota Banda Aceh, Aceh 23111, Indonesia.
*Corresponding author (mm_adie@yahoo.com).