Presentation: Potential NIRS Application for Plant Breeding and Production Research

Introduction

• Plant breeding is a long-term commitment to put agronomic, disease resistance, and quality characteristics together into an economically viable cultivar.
• The cost of quality testing and the time required for laboratory or animal testing is both expensive and limiting.
• Near Infrared Reflectance Spectroscopy (NIRS) is an excellent tool to screen large numbers of samples in a short period of time. The FCDC is able to analyze 30,000+ samples in 4 months.
• It is a nondestructive test, which requires a small sample size (50g). This allows the breeder to screen material at a very early stage in the breeding program.

• At the Field Crop Development Centre we have used NIRS successfully for over 20 years to determine protein, lysine, and starch in barley.
• Recent developments in computers and NIR equipment has allowed us to develop calibrations for over 50 grain and forage characteristics in barley, wheat and triticale.

• The FCDC is successfully using NIRS to predict malting quality characteristics on whole, unmalted barley samples.
• In our calibration set we included barley lines with good values for all malting quality characteristics, lines that were good for some but not all malting quality characteristics and some lines which were feed types which had good disease resistance or agronomic traits but did not have good malting characteristics. The set consisted of 1000 samples over 5 years.
• This population provided us with a large range of values from very good malting lines to very poor lines, and we were able to develop high-quality, robust NIR equations for malting quality using this population (Table1).

The calibration set for feed quality consisted of ten lines of barley from the Hulless Barley Cooperative Test. The lines were grown at various locations in western Canada over a period of three years. In total, 300 samples were collected. Protein Digestibility (PD), Energy Digestibility (ED) and Digestible Energy Content (DEC) were measured using digestibility trials with pigs. Crude Protein (CP) and Gross Energy (GE) were determined with the Kjeldahl procedure (N) and with an Adiabatic Bomb Calorimeter, respectively. All the equations developed had high R² values (Table 2). These equations are invaluable as a tool for screening feed quality characteristics in the FCDC breeding program.

Table 2. Equations Developed for Feed Quality

SEC = Standard Error of Calibration

Food Quality

• The same calibration set developed for determining feed quality was used for developing NIRS equations for food quality. While these samples had enough genetic variability, the range of constituent values was not very broad.
• These equations still have very high R² values and are extremely useful in selecting new barley lines for the food market (Table 3).
• These equations will help us identify new samples with either high or low values which we can add to our equations, expand the range of our calibration set and ultimately improve the robustness of the calibration.

Other NIR Equations Developed

As well as calibrations for grain, the FCDC has developed calibrations for forage quality, color and pearling traits (Table 4).

Table 4. Other NIR Equations Developed


SEC = Standard Error of Calibration

NIR Success at the FCDC

• The NIR success at the FCDC is partially due to the samples that have been selected for calibration development.
• We have found that the combination of genetic and environmental variability in a breeding program is advantageous in developing calibrations.
• What we strive for is to develop calibration sets that have the widest range of genetic and environmental variability as possible.
• We have found that at least 100 genetic combinations over a period of 3 years with 6 or more sites gives us the best calibration set for a robust calibration. However, even with this type of robust calibration set, we often need to add new genetic and environmental samples to a calibration over time.

• The use of NIR for ‘genetic fingerprinting’
• Our current work in NIR has shown that it can distinguish between 2-row, 6-row and hulless varieties, and can detect different environments.
• It seems possible to develop a NIR calibration that would be able to identify different barley lines and even different blends of varieties.
• Our current database of hundreds of thousands of samples would allow us to develop this calibration.
• Water Sensitivity
• Germination
• Seed Size
• Grain Phytate/ Phosphorus content

• NIR has allowed the breeding programs at FCDC to focus on developing new barley varieties for specific quality traits.
• This has speeded up the process of determining high quality lines for advancement.
• Over the last 10 years, the FCDC has made significant increases by selecting for protein digestibility (7.7% increase) and hulless barley digestible energy content (11.4% increase) (Figures 1&2)
• Without NIR, breeding new lines for these quality characteristics would be too expensive and time-consuming.

Funding has been provided by:

• Alberta Agriculture, Field Crop Development Centre (FCDC)
• Alberta Barley Commission
• Canada Malt Co., Calgary
• University of Alberta, Agricultural, Food and Nutritional Science