Inheritance of oleic acid trait and high throughput non-destructive phenotyping for nutritional traits in groundnut kernels

Abstract

The nutritional quality and food use of groundnut (Arachis hypogaea L.) is mainly governed by oil, fatty acids, protein, and moisture content of kernels. The breeding for higher proportion of oil, protein, and oleic acid in the kernels is an important objective, which needs a non-destructive, rapid, and reliable method for routine estimation in relatively large breeding populations. The present study reports the development of calibration equations in near-infrared reflectance spectroscopy (NIRS) for rapid and non-destructive estimation of kernel quality. Mode of inheritance pattern of a high oleic trait in groundnut was also studied. The best equation for each trait was selected based on the coefficient of determination in calibration and for cross-validation. The current equation gave high fidelity with the reference to biochemical value as indicated by high values of coefficient of determination in external validation (r2) for oleic acid (r2= 0.96), linoleic acid (r2= 0.96), moisture (r2= 0.96) and moderate for oil (r2= 0.89), protein (r2= 0.83) and palmitic acid (r2 = 0.80). The study further developed an efficient NIRS equation to deploy in groundnut breeding. The high oleic trait inheritance pattern was studied in F2:3 population derived from a cross between Spanish bunch normal oleic ICGV 06420 and high oleic SunOleic 95R parents. The results showed duplicate recessive inheritance pattern with a segregation ratio of 15: 1 (normal oleic: high oleic). The outcomes from the inheritance study helps to breed groundnut cultivars for high oleic trait.