Susceptibility of Cooking Herbs to Stored-Product Moths

Although herbs can contain several secondary metabolites potentially harmful to insects, dried herbs, like all stored foods, can be damaged by various insect pests. These pests have the potential to diminish both the quantity and the quality of food, and the consequences of infestation often only become noticeable once the pest has already become established. This study investigates the ability of two Lepidoptera pests, one polyphagous, Plodia interpunctella, and one selective, Idaea inquinata, to complete the postembryonic development on eleven dried herbs commonly used in cooking: dill (Anethum graveolens L.), basil (Ocimum basilicum L.), chervil (Anthriscus cerefolium (L.) Hoffm.), coriander (Coriandrum sativum L.), tarragon (Artemisia dracunculus L.), chives (Allium schoenoprasum L.), oregano (Origanum vulgare L.), parsley (Petroselinum crispum (Mill.) Fuss), sage (Salvia officinalis L.), savory (Satureja hortensis L.), and thyme (Thymus vulgaris L.). The results show that tarragon, sage, savory, oregano and thyme did not allow growth of either species, suggesting the presence of chemical compounds that limit larval growth or survival. In addition, the time required for both species to complete development was longer than that obtained on a standard diet, suggesting that the nutritional requirements and water content of the herbs are not as optimal as those of the standard diet. To conclude, I. inquinata could develop on basil, chervil, chives, coriander, dill, and parsley, while P. interpunctella could develop only on chervil, chives, coriander, and dill.