Which feeding method can cause deformities in plant parts or kill developing seeds?

Stink bugs are known for their piercing-sucking mouthparts, which they use to feed on a wide variety of plants. When stink bugs feed, they inject a saliva that contains enzymes capable of breaking down plant tissue. This damage can lead to various adverse effects, including deformities in plant parts or even the death of developing seeds. The saliva disrupts normal plant physiological processes, often resulting in malformed fruit and reduced yields.

In contrast, while caterpillars, beetles, and fungus gnats can also damage plants, their feeding methods and the type of damage they cause differ significantly. Caterpillars typically chew on leaves and may create holes but do not generally cause deformities to the developing seeds. Beetles, depending on the species, can damage plants through chewing but aren't primarily known for causing seed death on a large scale. Fungus gnats primarily affect plants in their larval stage, feeding on roots and organic matter in the soil, but are less likely to cause direct damage to developing seeds. Thus, stink bugs stand out as the primary cause of deformities or death in developing plant tissues due to their specific feeding method.