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Soybean cultivar with high pod-shatter resistance and good agronomic performances is essential for reducing yield loss in soybeans. The research aimed to evaluate the pod-shattering resistance and agronomic performance of soybean genotypes in the dry season. The experimental research was conducted in Probolinggo, East Java, Indonesia, from March to June 2019. The experiment used 150 genotypes and laid in a randomized block design with three replicates. Three sample plants were randomly taken after the R8 phase, and thirty pods were randomly taken for shattering evaluation using the sun-drying method. The result showed that the dry environment exacerbated the increase in pod shattering in soybeans climate. The screening for pod-shattering using the sun-drying method on the first day showed that 17 genotypes were resistant to pod-shattering, and 46 were resistant. The third day of sun drying revealed no very resistant genotype. On the fourth day of screening, it obtained six resistant genotypes (Anjas/IAC 100-1-183, Grobogan/G100H-8-342, Mahameru/IAC100-3-427, Mahameru/IAC100-3-937, G100H/Anjasmoro-3-181, and Mahameru/IAC100-2-426). Harvesting could be delayed by 4-5 days for resistant or very resistant genotypes in the dry season or dry climate environment. The number of nodes, number of branches, and number of filled pods were all significantly positively correlated with seed yield. The plant height has a significant positive correlation with the number of nodes and the number of filled pods. The GYT-biplot indicates two genotypes with the best performance for YLD*PS (Mahameru/IAC100-2-426 and Mahameru/IAC100-3-427). [ABSTRACT FROM AUTHOR]

Pod-sucking bug Riptortus linearis (Fabricius) is the most destructive soybean insect pest in Indonesia. The losses caused by this insect could reach 2–100%. This study aimed to determine the resistance level of 13 soybean lines to pod-sucking pests using no choice and free choice tests. The evaluation for resistance to the pod-sucking bug was performed using free-choice test (FCT) and no-choice test (NCT) methods. In FCT, all genotypes were placed in a meshed cage, meanwhile, in the NCT, each soybean genotype was individually placed in a meshed cage. Newly emerged adults R. linearis (n = 2 per plant) were infested during the R5 stage of the soybean. In the FCT, the range of pod damage intensity was 11.03–44.22% (average of 24.68%). Meanwhile, the seed damage intensity was ranged from 10.94–41.14% (average of 20.93%). In the NCT, the range of pod and seed damage intensities was 18.89–47.52% (average of 37.17%) and 13.19–72.38% (average of 37.74%), respectively. One genotype (G4) was identified as resistant based on the pod and seed damage in the FCT and NCT, respectively. Soybean genotypes that were consistently resistant based on the pod and seed damage in the NCT, as well as FCT methods, could potentially be used as gene sources for breeding soybean resistance to pod-sucking bug. The NCT method provides higher damage intensity than that of the FCT method. Thus, the NCT method could be used to screen soybean genotypes for resistance against pod-sucking bug to obtain genotypes with higher resistance level. [ABSTRACT FROM AUTHOR]