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Resistance against cotton bollworm is one of the main arguments for the use of genetically modified (GM) Bt cotton around the globe. The use of GM is prohibited in organic systems and thus the remunerative value of organic cotton cultivation depends on effective bollworm control. In this study, we investigated the extent of bollworm and sucking pest damage in 68 different hybrid and varietal lines of Gossypium hirsutum and varietal lines of G. arboreum at two different locations with contrasting soil fertility and water dynamics. The damage potential of bollworms was assessed from open capsules at two time points. Sucking pests were assessed at three time points using a scoring method. G. arboreum varietal lines and G. hirsutum hybrids were on average significantly more tolerant than G. hirsutum varietal lines to bollworm under fertile and irrigated situations. For sucking pests, the G. arboreum varietal lines were clearly more tolerant than G. hirsutum hybrids and varietal lines. Since, recently, pink bollworm (Pectinophora gossypiella) became resistant against Bt cotton and pressure of sucking pests severely increased, screening of genetic resources and systems-based cotton breeding for bollworm and sucking pest tolerance will improve sustainability of organic and conventional cotton production.

Core Ideas In a drought and non‐stress breeding program, secondary traits are important in contributing to the identification of high yielding and stability maize genotypes.Designing selection strategies that enhance grain yield gains and stability.The traits tassel size, ear aspect, ear diameter, and kernel weight per ear were found to have high broad sense heritability and can effectively aid simultaneous for selection for high grain yield and stability. Information is needed on the contribution of secondary traits to grain yield and stability in maize (Zea mays L.). This study aimed at identifying stable and high yielding hybrids as well as traits contributing to high yield and stability in tropical maize. Twenty‐two test hybrids and six check hybrids were evaluated under five environments in Karnataka, India, using a 4 × 7 α‐lattice design with two replications. Genotype main effect plus genotype × environment interaction biplot model was used to ascertain genotype stability and yield across environments. Genotype × trait biplot, t test, and step‐wise regression analyses were used to determine trait expression differences between high yielding and stable, and low yielding and unstable hybrids. Genotypic correlations and heritability were used to estimate correlated response to selection for grain yield via each secondary trait. Mean grain yield under drought was 20% of that across environments, thus selection in both drought and non‐drought stress environments is required. Hybrids GH‐12444 and GH‐12408 were high yielding and stable across environments, and should be tested widely. Some traits, such as tassel size, had correlated response to selection values of near unity making them unsuitable for indirect selection. However, such traits could be used to supplement selection for grain yield given their high heritability and that they are relatively easy to measure. Different traits were associated with grain yield under different conditions thus suggesting that both drought and non‐drought stress conditions must be used as selection environments using secondary traits specific to a given environment.

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