Decision-making system and natural factors determining the intensity of Liriomyza huidobrensis attack to tomato crops

• Ano de defesa: 2019
• Autor(a) principal: Lopes, Mayara Cristina
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Universidade Federal de Viçosa; Fitotecnia
• Palavras-chave em Português: Liriomyza huidobrensis; Parasitoides; Tomate - Doenças e pragas; Amostragem; Sistemas de suporte de decisão; Entomologia Agrícola
• Link de acesso: https://locus.ufv.br//handle/123456789/29774

The evaluation of agroecosystems and decision-making systems are essential in integrated pest management programs. Liriomyza huidobrensis (Diptera: Agromyzidae) is one of the major pests of tomato crops. Despite the importance of this pest, to date, there is no research on its spatiotemporal dynamics and on decision-making systems in tomato crops. Thus, the aims of this study were to determine: (i) the natural factors that regulate L. huidobrensis populations in tomato crops, (ii) conventional sampling plan, (iii) economic injury level (EIL) and (iv) sequential sampling plan for L. huidobrensis in tomato crops. The main natural enemies of L. huidobrensis were the parasitoids Diglyphus sp. (Hymenoptera: Eulophidae) and Opius sp. (Hymenoptera: Braconidae). The basal leaf of the middle section of the plant canopy was the best plant part for sampling. Leafminer densities were fitted to the negative binomial distribution with a common aggregation parameter (Kcommon = 0.7289). The sampling plan consists of 73 samples per field, irrespective of field size (1, 5 or 10 ha). Evaluations using this sampling plan were performed in 47 min, 1 h 9 min and 1 h 25 min with a cost of US $1.74, 2.54 and 3.12 per sampling in fields of 1, 5 and 10 ha, respectively. The EIL was 3.24 larvae per leaf. The sequential sampling plans made correct decisions in 100% of the situations, with sampling time and cost savings of 87%. Therefore, integrated management programs for L. huidobrensis should aim to preserve populations of Diglyphus sp. and Opius sp., which are important in the population regulation of this pest. The ideal sample for the evaluation of L. huidobrensis is the most basal leaf of the middle section of the tomato. The conventional sampling plan consists of 73 samples and is accurate, fast, representative and inexpensive. The EIL for L. huidobrensis in tomato crops is 3.24 larvae per leaf. The sequential L. huidobrensis sampling plan is suitable for use in integrated management programs in tomato crops for making correct decisions with time and costs savings.