Relationship of altitude, individual seed weight, and kernel colonization by Aspergillus flavus with biochemical parameters of various Ethiopian groundnut (Arachis hypogaea L.) accessions

Abstract

Groundnut is one of the five extensively grown oil crops of Ethiopia. Groundnut kernels contain 40-50% fat, 20-50% protein, and 10-20% carbohydrate and are rich in vitamin E, niacin, riboflavin, thiamine, falacin, calcium, phosphorus, magnesium, zinc, iron, and potassium. This study aimed to determine individual seed weight, kernel colonization by Aspergillus flavus, and biochemical parameters in groundnut seeds collected from different areas of Ethiopia. Groundnut germplasm in the form of seeds was collected from the Ethiopian Biodiversity Institute (EBI), further information about each accession location and altitude was also collected from the institute.  Parameters such as individual seed weight (ISW), kernel colonization by A. flavus, and biochemical parameters (i.e. total carbohydrate, protein, and total free amino acids) were measured in the groundnut seeds. A negative relationship between ISW and altitude (p<0.01) was observed in this study which indicates that an increase in altitude would result in a decrease in seed weight. A positive relationship between altitude with total carbohydrate (p<0.01) and with total free amino acids (p<0.05) was also observed. Low-ISW accessions exhibited significantly higher total carbohydrates while high-ISW accessions exhibited significantly higher total free amino acids in their seeds. Groundnut seeds of EBI accessions with 0% kernel colonization contained less total carbohydrate, and the accessions with 100% kernel colonization contained the highest total carbohydrates. Besides, total carbohydrates correlated positively with kernel colonization (p<0.01). So, it is postulated that high total carbohydrate makes groundnut seeds susceptible to A. flavus colonization.