Repeatability and number of measurements for productive variables in vegetable crops experiments

Resumo

The objetive of this study was to estimate the repeatability coefficient and the number of measurements necessary for the analysis of characters of production of Cucurbita pepo L., Cucumis sativus L., Capsicum chinese L., Pisum sativum L. The experiments carried out with Cucurbita pepo L. and Cucumis sativus L. the variables number of fruits, fruit mass, fruit length, largest fruit diameter and smallest fruit diameter were evaluated. For Pisum sativum L. the number of pods, mass of pods, pod length, number of grains per pod, mass of grains per pod and for Capsicum chinense L. number of fruits, fruit mass, largest fruit diameter e fruit length were evaluated. The repeatability coefficient (r) was estimated by the principal component method using the correlation matrix and the covariance matrix. The number of measurements for each variable was also determined based on the coefficients of determination of 0.80, 0.85, 0.90, 0.95 and 1.00. The estimated repeatability coefficient obtained the highest estimates using the covariance matrix, ranging from 0.67 to 0.84 for Cucurbita pepo L., from 0.66 to 0.97 for Cucumis sativus L., from 0.47 at 0.70 for Pisum sativum L. and from 0.57 to 0.71 for Capsicum chinense L.. To evaluate the fruit mass in Cucurbita pepo L., Cucumis sativus L., Pisum sativum L. and Capsicum chinense L., 7, 4, 8 and to evaluate the mass of pods 8 measurements are required, respectively, for 95% confidence in the results.