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Cape gooseberry ( Physalis peruviana ) fruit has gained recognition owing to its nutritional value and versatility to be consumed processed or as a fresh product. These characteristics have made it an important product in both national and international markets. One of the main limitations for this crop is Fusarium wilt caused by the fungus Fusarium oxysporum f. sp. physalis , for which biological control is emerging as an alternative to conventional management with chemical synthesis products. However, information on the effect that biological control agents have on the growth and development of plants is scarce. In this research, the physiological response of cape gooseberry plants (stomatal conductance, leaf water potential, growth parameters, total chlorophyll, carotenoid, and proline and malondialdehyde contents) to the treatment with three potential biocontrol agents (BCAs) Trichoderma koningiopsis , Trichoderma virens , and Bacillus velezensis was determined. The study was conducted under greenhouse conditions; F. oxysporum was inoculated in the soil, and BCAs were soil drenched in the germination and transplanting stages. Plants inoculated with the pathogen and plants without inoculation were used as controls. It was found that the plants inoculated and treated with T. virens showed the lowest disease levels (area under the disease progress curve of 48.5 and disease severity index of 2.1). Additionally, they showed a lower water potential (-0.317 Mpa), a greater leaf area (694.7 cm 2 ), and a higher stomatal conductance (110.3 mmol m -2 s -1 ) compared with the control. Consequently, it can be concluded that T. virens can be a good candidate for the management of Fusarium wilt in the cape gooseberry crop.

The Guatemalan moth Tecia solanivora is an invasive pest of potato in Central and South America. The larvae infest potato tubers in the field as well as in storage facilities. The headspace of potato foliage and potato tubers was studied with regard to volatiles that mediate host-finding and oviposition in the Guatemalan moth. Foliage of three phenological stages, from sprouting to tuberization and flowering, released more than 30 sesquiterpenes. The main compounds were beta-caryophyllene, germacrene-D-4-ol, germacrene-D, kunzeaol, and (E,E)-alpha-farnesene. Sesquiterpenes accounted for >90% of the headspace of green plants, whereas fresh potato tubers emitted only trace amounts of a few sesquiterpenes. Screening of headspace collections with antennae of Guatemalan moth females showed a strong response to several sesquiterpenes and monoterpenes that were emitted from foliage only. In addition, antennae responded to methyl phenylacetate, a floral fragrance that was released in large amounts from flowering plants and that was also present in tuber headspace. Female and male moths were attracted to methyl phenylacetate; this compound may accordingly contribute to female attraction to tuber-bearing potato plants in the field as well as to potato tubers in storage. Oviposition tests showed that females lay eggs near mature flowering plants. Eggs were laid in soil close to the plant and not on potato stems and foliage, which may be due to avoidance of terpenoid compounds released from green plant parts at close range. The results support the concept that potato volatiles mediate host-finding and oviposition behavior and that these compounds may become useful tools for management of the Guatemalan moth.