Morphogenetic and phytochemical characterization of korarima (Afframomum corrorima (braun) p.c.m. jansen) capsules collected from different growing regions of southwestern ethiopia

Abstract

Korarima (Aframomum corrorima (Braun) P.C.M. Jansen) is indigenous and important cash crop found diversified to various agro-ecologies of the country. However, it has been one of the most underutilized crops and yet minimal research attention was given to it. With an objective of assessing variations in phytochemical qualities, red capsules were collected from four growing regions of the southwestern Ethiopia at peak harvesting time, November and December 2011, using stratified random sampling method. The capsules were evaluated for the different phytochemical parameters at JUCAVM. According to the ANOVA result obtained from analyzing capsules and seeds physical characters significant (p<0.05) variations existed in terms of capsule length (CL), diameter and circumference, single fresh capsule weight, number of seeds per capsule, seed:husk ratio, seed length (SL), seed diameter and hundred seed weight. A significant (p<0.05) variation was also obtained from seeds quality traits such as volatile oil, oleoresin contents and proximate compositions. The mean values of the capsules and seed physical traits showed that the average CL and SL varied from 4.8 to 6.7cm and 3.56 to 3.89, respectively among the different samples. Fresh capsule weight ranged from 17.2 to 27.4g, seed number per capsule varied from 122.6 to 232.8 and hundred seed weight ranged between 1.39 and 2.34g. The mean values of seed phytochemical traits showed that volatile oil content ranged from 0.9 to 3.2 (v/w%) and oleoresin content ranged from 2.2 to 7.8 (w/w%). The results from proximate analysis revealed that the percentage mean values were within a range of 11.05 to 13.01 moisture, 7.4 to 48.4 crude fiber, 1.25-2.85 crude fat, 3.08 to 15.38 ash, 6.87 to 7.95 crude protein and 26.12 to 61.01 carbohydrate contents. Results from Principal Component (PC) analysis indicated that based on capsule and seed physical traits the first five PCs explained 89% from the total variation from which PC1 and PC2 account for 29.9% and 23.6%, respectively whereas based on seed biochemical characters PC1 and PC2 contributed 25.3% and 18.5%, respectively. Cluster Analysis based on capsule and seed phytochemical traits grouped the samples into four groups. Cluster I, III and IV were formed by less number of samples whereas cluster II contained fifteen samples of various agro-ecologies. Samples from different geographical locations fall under the same clusters. This may be an indication that domestication of korarima from existing gene pool in different areas of cultivation. The overall result showed that there is variability in phytochemical traits among korarima samples of different regions. The variation may be linked to varietal, environmental, edaphic factors and/or management practices. The results obtained may contribute for further breeding and quality improvement purposes. Due to high potential of korarima production in the country, further and concerted efforts would be imperative research including the untouched areas.