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Defenses Against Herbivory
N. attenuata has been observed to utilize direct and indirect defenses against herbivory. Their main predators are Hawkmoth larvae known as the tobacco hornworm (Manduca sexta) and tomato hornworm (Manduca quinquemaculata). When these worms eat trichomes on the tobacco leaves the plant produces trypsin proteinase inhibitors as a direct defense, weakening the hornworms ability to digest plant material. As an indirect defense, when the leaves are eaten by larvae, the plant emits green leaf volatiles (GLVs) that attract Geocoris bugs, which are predators of the worm. These GLVs are one of many Herbivory-induced plant volatiles (HIPVs) that N. attenuata emits via jasmonic acid signaling. When GLVs come into contact with saliva from the hornworm there is a conformation change in the GLVs that attracts Geocoris spp and increases predation on the hornworm eggs and larvae. It has also been discovered that wild tobacco responds to volatile organic compounds (VOCs) emitted from other proximate species and undergoes priming of defenses.

Another indirect defense that has recently been studied is a change in flowering time and phenology, prompting a change in pollinator from the night-active Hawkmoth to day-active hummingbirds. The flowers of N. attenuata normally open at dusk and are exposed during the night where Hawkmoth pollination occurs coupled with oviposition and thus future herbivory by Hawkmoth larvae. Saliva from the hornworm causes a jasmonic acid transduction cascade leading to changes in flower phenology. Flowers reduce benzyl acetone (BA) concentrations, a Hawkmoth-attracting volatile, and shift corolla opening to dawn, where day-active hummingbird pollination prevails and herbivory by the Hawkmoth larvae is lessened. This shift from night opening to morning opening flowers was discovered using a native population of N. attenuata in Utah. Mesh coverings were placed over selected plants in different test groups with hornworms present or absent, and through a series of trials the ratio of morning opening to night opening flowers after just 8 days was significantly increased in the plants with hornworms present. .

Collectively, these direct and indirect defenses show the impressive plasticity in behavior of N. attenuata in responding to herbivore attack.