Abstract

RODRIGUES, Raúl et al. Sampling plan for Green-Leafhoper (Homoptera: Cicadellidae) in vineyard at Lima Valley. Rev. de Ciências Agrárias [online]. 2012, vol.35, n.2, pp.213-220. ISSN 0871-018X.

The aims of this work were: to study the spatial patterns of nymphal stages of the green-leafhopper Empoasca vitis using the regression models of Taylor's Power Law and Iwao, in vineyard cvs. Arinto and Vinhão in organic farming and integrated production systems; to develop a binomial sampling (presence-absence). The results showed that: i) Taylor's power law was more appropriate to describe the spatial pattern of E. vitis and indicated a random pattern; no statistically differences were detected between varieties and production systems, ii) the sample size required increases with the degree of accuracy, iii) it is possible to simplify the enumerative sampling plan; and iv) the sample size required to estimate population densities of this pest corresponding to the economic thresholds, ranges from 30 to 57 leaves.

Keywords : Binomial sampling; Empoasca vitis; sample size; spatial pattern.

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