IRRI SERVICE LABORATORIES

provides quality and efficient integrated laboratory testing services and expertise

Physical traits

Physical trait for grain dimensions (length and width) and chalk are measured using SeedCount SC5000 Image Analyzer. Length and width are used to determine the class of the rice. While chalk area of the grain is present due to malformed starch granules with air spaces between them. Milled grains are placed in a tray, scanned and analyzed for chalkiness and dimensions (length and width). Broken grains are disregarded for chalk, length and width measurements.


Note: For determination of physical traits, the sample weight required is at least 6 g of milled rice  placed in a coin envelope. In order to keep the integrity of the customers' samples, senders are requested to place them in secured plastic boxes. 

References:
Module 3: breeding program management, lesson 3: breeding for grain quality. IRRI 2006. Accessed January 2015. http://www.knowledgebank.irri.org/ricebreedingcourse/bodydefault.htm#Grain_quality.htm
SeedCount SC5000 Image Analyser tutorial video. Accessed January 2015. Next Instruments.
Sreenivasulu, N. (2018). Rice Grain Quality: Methods and Protocols. New York, NY: Humana Press.