Avaliação do desempenho de sementes de soja produzidas na região de Chapada - RS, na safra 2014/15

Abstract

The soybean crop (Glycine max), with a perspective of the expansion of its area in Brazil, reached the highest growth in the last three decades due to several factors. Some of them refer to the use of selected seeds and improved by the genetic improvement, having thus a high quality and adapted to the different productive environments. But even though they have some comparative advantages in relation to seed saved, the rate of use of legal seeds is not always encouraging, a factor that worries the sowing sector throughout the country due to the growth of the practice of "seed rescue" and / Or piracy thereof. Thus, the objective of the study ,produced in the Chapada RS region, as well as to raise possible reasons for farmers to save seeds. For this, seed samples from seed producers and seed multipliers from the municipality of Chapada, located in the state of Rio Grande do Sul, were collected. A questionnaire was also applied to the farmers with closed questions related to the practice of saving seeds . After being collected, the samples were taken to the Laboratory of Seed Analysis of the Universidade Tecnológica Federal do Paraná-Campus Dois Vizinhos. Germination, accelerated aging, field emergence, emergence velocity index, sieve retention, mechanical damage and seed health were evaluated. With the aid of charts and tables, a qualitative comparison was made between the lots of producer seeds and the seed lots from the multiplier companies. The results showed that the commercial seeds presented greater vigor by the test of speed index of emergency. All the seeds sampled (salves and commercial ones) presented high index of mechanical damage. With regard to sieve standardization, commercial seed lots were more homogeneous. For the storage fungi, there was a higher incidence in the seeds saved and the phytopathogenic fungi, there was incidence in all seed lots, of the Fusarium fungus. Thus it is possible to conclude that the commercial seeds present a better physical, physiological and sanitary quality than the seeds saved, but must improve their production process. The farmers of the region, carry out the rescue of seeds by tradition and reduction of the cost of production.