Eileen Perry1,2, Audrey Delahunty3, James Nuttall4, Alex Clancy4, Ashley Wallace4
1 Agriculture Victoria, 1-7 Taylor Street, Epsom, VIC 3498; email@example.com
2 The University of Melbourne, Parkville, VIC, 3000, Australia
3 Agriculture Victoria, Cnr Eleventh St & Koorlong Ave, Irymple, VIC 3498
4 Agriculture Victoria, 110 Natimuk Road, Horsham, VIC 3400
Frost can have negative impacts on both yield and quality of lentil, and currently there is a gap in methods to provide growers with tools to identify, monitor and assess the degree of damage due to frost. To evaluate the potential for spatial, non-destructive detection of frost damage, a trial was established in lentil (cv. Jumbo 2) using active frost treatments over a range of growth stages and intensities. Proximal sensing was used to monitor the crop to determine whether non-destructive methods can detect frost damage, and if post-processing can separate frost effects from natural crop senescence. The results show that in addition to the proximal measurements detecting natural senescence occurring during the period from flowering to pod fill, it also detected a decrease in canopy chlorophyll associated with cold exposure, beyond a threshold cold sum value (5 – 31 ˚C.hr). SFR_G from active fluorometer measurements was fit to cold sums, resulting in R2 values of 0.84 six days following frost application at flowering, and 0.72 eight days following frost at pod filling. NDVI from canopy reflectance measurements was related to cold sums across pooled measurement dates with an R2 value of 0.81. The reflectance index PRI increased with increasing cold exposure, indicating changes in photosynthetic efficiency with increasing frost damage. These initial results agree with previous research on detection of frost damage in wheat.