The yield of fruiting bodies of <i>Agaricus bisporus</i> from compost is variable due to differences in available nutrients and cultural conditions during production. The objective of this study was to evaluate the use of near-infrared (NIR) reflectance spectroscopy for assessing potential compost productivity. Three compost comparative trials, carried out over the past six years under controlled experimental conditions, have generated a large sample set (48 X 3 = 144) with yield data. Visible and NIR reflectance measurements of the calibration samples were made over the range of 400-2498 nm. A partial least-squares (PLS) algorithm was used to generate the predictive models using the information in the spectrum. A model developed with the spectral region 1100-2498 nm could explain 87% of the variation in mushroom yields obtained from the three trials. The accuracy of the NIR yield model has been confirmed in a validation compost comparative trial. A combined calibration equation (<i>r</i><sup>2</sup> = 0.93) using the spectral data (1100-2498 nm) from the four trials was developed with a standard error of cross-validation of 18.6 kg/tonne.
H. S. S. Sharma and M. Kilpatrick, "Use of Near-Infrared Spectroscopy to Predict Potential Mushroom (Agaricus bisporus) Yield of Phase II Compost," Appl. Spectrosc. 54, 44-47 (2000)