Procedures for the conduction of the electrical conductivity test for the evaluation of maize seed vigor

Author(s)

José Luís Marchi

• Document type: Master's Dissertation
• Press: Piracicaba.
• Institution: Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC)
• Defense date: 2001-12-27
• Advisor: Silvio Moure Cicero

Abstract

The research was conducted at the Seed Analysis Laboratory and in an experimental area of the Vegetal Production Department at Escola Superior de Agricultura "Luiz de Queiroz", University of São Paulo, with the objective of studying different procedures for the bulk conductivity test for the evaluation of vigor in maize seeds. For this experiment, three seed lots of C032 hybrid, with different levels of mechanical damages were submitted to the electrical conductivity test, using samples with 25, 50 and 100 seeds. For each sample the test was conducted with previously chosen seeds (the ones with no visible mechanical damages) and with seeds without previous choice (original samples). Simultaneously complementai vigor tests were conducted (cold test, accelerated aging, and field emergence) with the aim of establishing relations with the adopted procedures on the conduction of the conductivity test and, by this way, to select the most adequable procedure for the conduction of the conductivity test. After the definition of the most adequable procedure, the bulk conductivity test was done with the three seed lots treated with fungicides (Maxim XL, Captan 750 TS and Vitavax - Thiram 200 SC), inseticides (K-obiol and Actelic) and the association of both, with the aim of verifying the influence of then on the evaluation of bulk conductivity. The results obtained, showed that, with the exception of the procedures which used 100 seeds without previous choice and 50 seeds with choice, ali the procedures were efficient for the conduction of the electrical conductivity test for maize seeds. The maize seeds treatment with the fungicides Maxim XL, Captan 750 TS and Vitavax - Thiram 200 SC didn't interfere on the conductivity of the solution, otherwise, in a general way, the mixture of the inseticides K-obiol and Actelic, and their association with the fungicides, increase those values, however the seeds chemical treatment didn't cause changes on the lots vigor classification. (AU)