Full text
| |
| Author(s): |
José Luís de Marchi
Total Authors: 1
|
| Document type: | Doctoral Thesis |
| Press: | Piracicaba. |
| Institution: | Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC) |
| Defense date: | 2010-09-30 |
| Examining board members: |
Silvio Moure Cicero;
Maria Laene Moreira de Carvalho;
Leila Martins;
Maria Heloisa Duarte de Moraes;
Roberval Daiton Vieira
|
| Advisor: | Silvio Moure Cicero |
| Abstract | |
Peanut seeds are considered difficult to produce, since they have often unsatisfactory levels of germination and vigor due to many factors, including problems due to the occurrence of fungi, and are very susceptible to mechanical damage. In this aspect than the use of routine tests for evaluation of seed quality, the use of image analysis techniques, such as the X-ray test has great potential, because, it is a precision method, where the seeds can be examined individually in enlarged images and able to indicate, in detail, areas injured, location and extent of the injuries. Because it is non-destructive method, the seeds being analyzed can be subjected to physiological tests and thus allow the confirmation of the observed damage. The objective of this work was to study the effects of peanut seed treatment with fungicide and insecticide, as well as the combination of both, in the physiological and sanitary quality of seeds, with the aid of this technique. For this, seeds of the cultivars IAC Tatu ST and IAC 886 untreated and treated with fungicide Maxim XL (fludioxonil + metalaxyl) with the insecticide Cruiser 350 FS (thiamethoxam) and a mixture of both products were subjected to periods of storage 0, 15, 30, 45, 60, 90 and 180 days. After each storage period, seeds were tested with X-rays, and the germination test, determination of moisture content and accelerated aging, seedling emergence in the field, electrical conductivity, and health test. The experiment was conducted in two years, using for the first year the seeds of cultivar Tatu ST and the second year the IAC 886. Also, in order to exploit the great potential of image analysis techniques, the seeds of the cultivar IAC 886, used for conducted the second year of the experiment, were subjected in parallel to the test of vigor by means of computerized analysis of seedlings, using, the automated system SVIS ®. The survey results showed that treatment of peanut seeds with fungicide or fungicide + insecticide provides effective control of fungi and preservation of the physiological quality up to 60 days of storage (20 ° C, 50% RH). The X-ray test is effective in identifying the mechanical injuries and lesions associated with damaged tissue, allowing to establish relationships between their occurrence and damage caused to germination. The computer analysis system has efficiency equivalent to accelerated aging and growth test to identify differences between treatments with the absence or presence of fungicide and fungicide associated with insecticide in peanut seeds. (AU) | |