Abstract
Common bean genotypes were grown in three different growing sites and analyzed for 17 mineral compositions. The influence of growing sites was observed on all seed mineral contents however, ratio of genotypic variance to genotype x environment variance indicated greater influence and stability of genetic factor on Ca and Sr. It was observed that the Zn concentration is highly correlated with S and Fe and Ca with Sr in common bean seed.
INTRODUCTION
Micronutrient malnutrition is a primary health care issue and currently, by any measure, it is of alarming proportions in many developing nations. Minerals like aluminum (Al), Boron (B), beryllium (Be), calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), molybdenum (Mo), potassium (K), sodium (Na), nickel (Ni), phosphorus (P), sulfur (S), strontium (Sr), titanium (Ti), and zinc (Zn) are essential and necessary for normal growth, reproduction, and health (Phan-Thien et al. 2010). There are limited crop breeding program focused on enhancement or improvement mineral composition, with the notable exception of a large CGIAR program aiming to increase only bioavailable Fe, Zn, and carotenoids in a number of staple food crops (Welch and Graham 2004). The common bean (Phaseolus vulgaris L.) is a principal grain legume and a valuable source for minerals or micronutrients. However, minerals contents in this crop, like any other plant, dependent on the availability of minerals in soil environment and interaction among soil compositions. The objectives of this study were to 1) estimate the influence of environment, genotype, and their interaction on the composition various minerals in common bean seed, 2) identify variability of micronutrients in common bean seed, and 3) association among the minerals in bean seed.
MATERIALS AND METHODS
Plant Materials
Samples were comprised with 11 common bean genotypes involved as parents of several mapping populations. In the Mayville State University green house, common bean genotypes were grown in pots filled with Sunshine mix 1. Seeds of each genotype were also grown in two field locations of North Dakota State University in summer 2010.
Mineral Content Analysis
After harvesting, seeds from each pod of individual plant were mixed thoroughly and 10 seeds were ground in liquid nitrogen and closed acid digestion was performed 250 mg of sample in 5 mL of concentrated nitric acid, and 5 mL of water. Analyses of 17 mineral concentrations were performed on Spectro Genesis Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) using Smart Analyzer Vision software (v. 3.013.0752).
Data Analysis
Seed mineral contents data were analyzed for identifying the influence of genotype, environment, and genotype x environment on mineral content. The simple correlation analysis was performed among different minerals using the SAS 9.2.
RESULTS AND DISCUSSION
Significant influence of genotype (G), environment (E), and GxE were observed on all mineral compositions in common bean seed. A ratio of the variance associated with the environmental effects (σ2E) to the genetic effects (σ2E) larger than 1.0 indicates the greater influence of environemnt and less than 1.0 indicates greater influence of genetic factors. Ratios of variances between environmental effect and genetic effects (Table 1) indicated highest influence of environment on the variability of Mo concentration (23.30) in common bean seed followed by Cu (8.14), S (3.54), Ni (2.96), Zn (1.51), Mn (1.29), and B (1.28). Greatest influence of genetic factor on the variability of Ca concentration (0.22) was observed in common bean seed followed by Al (0.24), and Ti (0.66). Almost equal influences of environment and genetic factors were observed for variabilty of Fe 0.90, K 0.86, and Sr 1.06.
Table 1.
Ratio of variances associated with environment effect to Genetic effect and genetic effect to genetic X environment effect on seed mineral compositions in common bean
| Al | B | Ba | Ca | Cu | Fe | K | Mg | Mn | Mo | |
|---|---|---|---|---|---|---|---|---|---|---|
| S2E/S2G | 0.25 | 1.28 | 3.37 | 0.23 | 8.14 | 0.90 | 0.86 | 8.68 | 1.29 | 23.30 |
| S2G/S2GxE | 0.13 | 0.08 | 0.07 | 1.91 | 0.28 | 0.66 | 0.07 | 0.10 | 0.05 | 0.22 |
| Na | Ni | Mo | Na | Ni | P | S | Sr | Ti | Zn | |
| S2E/S2G | 30.14 | 2.96 | 23.30 | 30.14 | 2.96 | 4.19 | 3.54 | 1.06 | 0.66 | 1.51 |
| S2G/S2GxE | 0.02 | 0.52 | 0.22 | 0.02 | 0.52 | 0.01 | 0.10 | 1.34 | 0.03 | 0.25 |
A variance component ration of σ2G/σ2GXE (Table 1) larger than 1.0 indicates greater influence and stability of genetic factors relative to the variability associated with the interaction of genotype and environment. The ratio of (σ2E/σ2G) indicated a higher influence of genotype on the concentrations of Ca, Al, and Ti but the ratio of σ2G/σ2GXE indicated the greater influence and stability of genetic factor on Ca concentration in common bean seed. Although the equal contribution of environment and genotype on the concentration of Sr was indicated but a ration of σ2G/σ2GXE over 1.0 (1.34) indicated the greater influence and stability of genetic factor in controlling the Sr concentration in common bean seed. To exclude any false positive, we considered correlation with higher R values (R > 0.55). The highest correlation was observed between Zn and S (R = 0.878) followed Sr and Ca (R = 0.871) and Zn and Fe (R=0.867). The correlation between Zn with P and Fe also reported by Gelin et al. 2007 and between Zn and Fe by Pfeiffer and McClafferty (2007).
Table 2.
Correlations among minerals in common bean seed
| Al | B | Be | Ca | Cu | Fe | K | Mg | Mn | Mo | Na | Ni | P | S | Sr | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Al | |||||||||||||||
| B | 0.067 | ||||||||||||||
| Be | −0.02 | 0.387 | |||||||||||||
| Ca | 0.076 | 0.407 | −0.12 | ||||||||||||
| Cu | 0.199 | 0.290 | 0.057 | 0.476 | |||||||||||
| Fe | 0.281 | 0.050 | −0.19 | 0.210 | 0.07 | ||||||||||
| K | 0.047 | 0.184 | −0.46 | 0.526 | 0.57* | 0.34 | |||||||||
| Mg | −0.15 | 0.224 | 0.104 | 0.401 | 0.74* | 0.03 | 0.64* | ||||||||
| Mn | 0.186 | 0.278 | 0.79* | 0.044 | −0.05 | 0.27 | 0.371 | 0.06 | |||||||
| Mo | 0.250 | 0.344 | −0.33 | 0.023 | −0.51 | 0.41 | −0.07 | −0.49 | 0.032 | ||||||
| Na | 0.012 | 0.332 | −0.21 | −0.11 | −0.31 | 0.66* | 0.170 | −0.24 | 0.180 | 0.307 | |||||
| Ni | −0.23 | 0.059 | 0.391 | 0.203 | 0.70* | −0.25 | 0.432 | 0.56* | 0.091 | −.496 | −0.16 | ||||
| P | 0.221 | −0.02 | −0.26 | 0.497 | 0.63* | 0.41 | 0.82* | 0.59* | −0.06 | −0.20 | 0.234 | 0.36 | |||
| s | 0.073 | −0.04 | −0.27 | 0.109 | 0.026 | 0.84* | 0.484 | 0.154 | 0.18 | 0.29 | 0.81* | 0.02 | 0.49 | ||
| Sr | −0.03 | 0.484 | 0.166 | 0.87* | 0.61* | 0.04 | 0.319 | 0.408 | 0.167 | −0.16 | −0.33 | 0.26 | 0.34 | 0.08 | |
| Ti | 0.83* | −0.08 | 0.019 | −0.05 | −0.18 | 0.27 | −.04 | −0.12 | 0.118 | 0.100 | 0.119 | −0.1 | 0.20 | 0.07 | 0.13 |
| Zn | 0.198 | 0.024 | −0.20 | 0.195 | 0.035 | 0.87* | 0.50 | 0.194 | 0.196 | 0.341 | 0.64* | −.10 | 0.57* | 0.88* | 0.03 |
Indicate >1% level of probability
Acknowledgments
The project was supported by NIH and NIGMS grant P20RR016741 from the INBRE Program.
References
- Welch RM, Graham RD. J Exp Bot. 2004;55:353–364. doi: 10.1093/jxb/erh064. [DOI] [PubMed] [Google Scholar]
- Phan-Thien KY, Wright GC, Lee NA. J Agric Food Chem. 2010;58:9204–9213. doi: 10.1021/jf101332z. [DOI] [PubMed] [Google Scholar]
- Gelin JR, Forster S, Grafton SK, McClean PE, Rojas-Cifiientes GA. Crop Sci. 2007;47:1361–1366. [Google Scholar]
- Pfeiffer WH, McClafferty B. Crop Sci. 2007;47:S-88-S-105. [Google Scholar]