Resumo

ORTIZ DOMINGUEZ, Aída  e  OJEDA MUNOZ, Marjorien. Evaluation of milling quality and grain dimensions of two rice varieties and their weedy rice variety types. Agronomía Trop. [online]. 2006, vol.56, n.3, pp.345-368. ISSN 0002-192X.

In this study the milling quality of Weedy rice-variety types (WRVT) originated from seed fields planted with D-Sativa and Fedearroz 50 was considered. Treatments were: D-Sativa, DS-B, DS-R, Fedearroz 50, FD-B and FD-R. A completely randomized experimental design with five replicas was used. Data were subjected to analysis of variance using SAS Software and mean Tukey at the 5% level of probability. Attributes associated with milling quality were measured. Rice varieties, Oryza sativa L., showed higher % of head rice (HR) than WRVT. The WRVT with red pericarp (FD-R y DS-R) showed approximately 10% less in HR than D-Sativa and Fedearroz 50, while the beige types showed a lesser difference (2%) with respect to their varieties of origin. However, the WRVT had more chalky+white belly grains (4,29% y 8,82%) than the varieties (3,35 y 3,68%), and the red types (5,46% FD-R y 8,82% DS-R) more than the beige ones (4,28% FD-B y 5,34% DS-B). Only the red WRVT showed red grains in polished rice (GRP), and of these, DS-R (21,31%) had 4,6 times more GRP than FD-R (4,64%). FD-R, FD-B and DS-B showed similar grain length as the varieties (>9mm), while DS-R had the shortest (8,58 mm) and widest (3,20 mm) grains in paddy. These results suggest that rice milling quality maybe affected by the presence of WRVT in rice paddy.

Palavras-chave : Oryza sativa L; weedy rice-variety types; Fedearroz 50; D-Sativa; milling quality.