To Effectively Control Tuta absoluta (Meyrick) and Improve Crop Yields, Consider Exploring the Benefits of Intercropping Tomatoes with Garlic

Abstract

Diversifying agroecosystems is crucial for maintaining ecosystem functions, including pest control, beneficial insect diversity, and soil fertility. In this study, the impact of intercropping tomato (T) (Lycopersicon esculentum (Mill.) and garlic (G) (Allium sativum L.) in three designs of 4E:4G, 4E:8G, and 4E:12G (row ratios) were assessed on the density of the tomato leafminer (TLM), Tuta absoluta (Meyrick), fruit infestations, diversity of tomato-dwelling predators, parasitism rate, and crop yields compared with the sole crops over two growing seasons of 2022 and 2023. Three intercrops caused a significant reduction in the number of TLM eggs, larvae, and galleries, as well as the percentage of infested fruits compared to the sole tomato plots. The abundance of primary predators, Nesidiocoris tenuis (Reuter) and Orius niger (Wolff), were higher in intercrops compared to sole tomato plots. Furthermore, the annual abundance of tomato-dwelling predators enhanced in the intercrops than in the sole tomato plots. Besides, there was a noticeable enhancement in the Shannon diversity index for tomato-dwelling predators (the values of 1.98 in 4T: 4G in 2022 to 2.31 in 4T: 12G in 2023) compared to the values of 1.68 in 2022 and 1.82 in 2023 for sole tomato plots. The land equivalent ratio (LER) showed a notable improvement, ranging from 1.19 in 2022 to 1.32 in 2023 in the 4T: 12G intercrop, in intercrops compared to sole crops. Therefore, farmers may consider the implementation of the aforementioned intercrops as a strategy for the integrated management of T. absoluta infestations in their tomato fields.