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The nut scale, Eulecanium tiliae (L.) is a potential pest, infesting deciduous trees in Iran, where it is common in urban horticultural areas and usually present in high population on some stone fruit trees, such as Prunus spp., including Prunus cerasus. It has higher occurrence and population in sustainable orchards. This pest has one generation per year and second nymphs overwinter on one or two-years old branches. High populations of this pest can cause death of branches, twigs and degeneration of leaves chloroplasts. In this research, the spatial distribution pattern and population fluctuation for all stages of E. tiliae were investigated in a cherry orchard of Kermanshah region during two studied seasons from 2016 to 2018. Four different methods were used to calculate distribution pattern including index of dispersion, Morisita's index and regression methods (Taylor's and Iwao's). Sample size was determined for the first time, according to a primary sampling date and corrected for other sampling dates according to the data of the previous sampling date. Data analysis was performed using Minitab16 and Office Excel 2016 statistical softwares. Most used methods revealed aggregated distribution pattern of the pest in both years. The results obtained from the Morisita's index during activity showed the random distribution of the second nymphs (in 16 April 2016, Z= -1.218, Iб= 0.440) (in 16 April 2017, Z= -0.179, Iб= 0.942) (-1.96< Z< 1.96). These changes showed that the spatial distribution could change during the season. Knowledge of the pest spatial distribution pattern can be used to arrange sampling program in pest management. [ABSTRACT FROM AUTHOR]

The Taylor power law (or temporal fluctuation scaling), is a scaling relationship of the form σ ~ (P)λ where !! is the standard deviation and hPi the mean value of a sample of a time series has been observed for power output data sampled at 5 min and 1 s and from five wind farms and a single wind turbine, located at different places. Furthermore, an analogy with the turbulence field is performed, consequently allowing the establishment of a scaling relationship between the turbulent production IP and the mean value (P).

Abstract: Firm-level data for a small sample of European countries are used to provide evidence of a positive linear relationship between the mean and the variance of firms’ size at a sectoral level, an empirical regularity known in mathematical biology and ecology as Taylor power law. We recur to computational experiments to show how this empirical fact can be fruitfully employed to discriminate amongst alternative theoretical explanations of firms’ growth. [Copyright &y& Elsevier]

Abstract: Sequential sampling programs for the management of Oriental tobacco budworm, Helicoverpa assulta (Guenee), on red hot peppers were developed using the data of damaged pepper fruits by H. assulta. Taylor''s power law indicated that the damaged pepper fruits were distributed randomly in hot pepper fields. A fixed-precision-level sequential sampling plan for classifying fruit damage density levels at a critical density of 2 damaged fruits per plant was developed to assist in decision making. The sequential classification sampling plan was evaluated using the operating characteristic (OC) and the average sample size (ASN) curves. The OC and ASN curves indicated that this sampling plan was robust and properly classified the population density. A resampling simulation demonstrated that average actual sampling precision value at D =0.25 was ≤0.25. With sequential sampling for classifying the damaged fruit levels in terms of a critical density, sample size was fixed to 18 plants. The fixed-precision-level sequential sampling plan developed in this study should greatly enhance the monitoring efficacy and provide practical solutions suitable for reliable decision-making process in the management of H. assulta. [Copyright &y& Elsevier]

During a 4-yr period (1988-1991), Colorado potato beetle, Leptinotarsa decemlineata (Say), eggmass, larvae, and adult populations in 17 commercial eggplant, Solanum melongena L., fields were sampled twice weekly using a 100-plant fixed sampling program. Eggmass and combined adult/larvae (placed on an equivalent feeding basis) densities were determined. The Taylor power law was calculated for use in developing sequential estimation sampling plans. Two plans were created, 1 for eggmasses and 1 standardized for combined adults and larvae. Resampling for validation of sampling plans software was used to test each plan using 18 independently collected data sets from 2 eggplant fields during 1992. Each year, beetle densities ranged between 0.0 and 8.0 for eggmasses and between 0.0 and 55.0 for combined larvae/ adults. Application of the Taylor power law to the data resulted in a significant linear relationship between the means and variances for each year and described aggregated sampling distributions for both eggmasses andcombined adults/larvae. Based on the lack of significant differencesin regression slopes between years, combined year values for the Taylor a and b (eggmasses, a = 1.74, b = 1.18; combined adults/larvae, a= 3.55, b = 1.56) were calculated and used to generate optimal sample sizes and critical stop lines. The simulations conducted to validate each sampling program resulted in mean precision levels for each data set tested that were lower than the precision level specified (D =0.25). The simulations also showed a high degree of agreement between actual an estimated densities on all sampling occasions. [ABSTRACT FROM AUTHOR]