Sample size determination for maize plants and cob traits under straw management at sowing

Abstract

Certain types of management in maize crop experiments (Zea mays L) can determine sample size. This study aimed to estimate the sample size needed to determine traits of maize plants and cobs under various straw management and sowing methods in large plots. The experiment was performed in the experimental area of the Federal University of Technology in Paraná (Universidade Tecnológica Federal do Paraná - UTFPR), Pato Branco, Paraná. Different managements methods of oat straw were subjected to four sowing methods using plots with five 20 m long rows spaced at 0.8 m. A total of five traits were evaluated on 10 plants and four traits on eight cobs. The 95% confidence interval was estimated using 5,000 bootstrap simulations. For an error equal to 10% of the mean, the sample size for plant and cob insertion heights and stem diameter is less than six, and for cob length, diameter, number of rows and number of kernels per row, the sample size is less than five. The type of straw management and the method of sowing did not affect the sample size for traits of plants and cobs.