Resumo

SOFIATTI, Valdinei et al. Effects of the growth regulator, disease control and sowing density on the industrial quality of rice grains. Cienc. Rural [online]. 2006, vol.36, n.2, pp. 418-423. ISSN 0103-8478.  http://dx.doi.org/10.1590/S0103-84782006000200010.

This study was carried out to evaluate the application effects of the growth regulator ethephon on the flowering and maturation uniformity and disease control at the end of the crop cycle. The effect of the fungicide tebuconazole, on the grain quality of the cultivars IRGA 417 and El Paso L 144 was evaluated in two sowing densities. The experiment consisted of a factorial combination (2x2x4) of two cultivars (IRGA 417 and El Paso L 144), two sowing densities (50 and 150kg ha^-1) and four leaf treatments (1-no chemical treatment, 2-ethephon, 3-fungicide, 4-ethephon + fungicide). The experimental design was a randomized complete block with three replicates. Percentage of whole grains and partially plastered grains were determined. The percentage of the whole grains was similar in all treatments, except for the application of ethephon + fungicide in the cultivar IRGA 417, and showed the lowest percentage of whole grains. There are interaction among the cultivars, sowing densities, and leaf treatments for the percentage of partially plastered grains. Plastering occurrence was higher in El Paso L 144, although the application of ethephon at the sowing density of 150kg ha^-1 provided high reduction in the plastered grain percentage.

Palavras-chave : florescence uniformity; partial plastering; ethephon; whole grains.