MSI07P4269 | |
Badaloo, M. G. H. Ramdoyal, K. | |
Use of predictive statistics for early identification of genetic potential of sugarcane families to produce elite genotypes in advanced trials | |
periodical | |
2007 | |
Proc. int. Soc. Sug. Cane Technol. | |
26: 646-656 | |
En | |
En Sp Fr | |
The identification of crosses that have the highest probability of producing elite genotypes is a desirable feature to enhance the efficiency of sugarcane breeding programs. Studies were carried out with 20 biparental crosses to assess their genetic potential and the application of predictive statistics in the superhumid environment of Mauritius. A number of agro-morphological characters were measured on random samples of progenies at the seedling and the replicated 3rd clonal stages: breeder's preference (BP), stalk number (SNO), stalk diameter (SDIA), stalk height (SHT), and plot yield (PY). Selection was performed at the 3rd clonal stage based on kiloBrix probability (field Brix x plot weight) on cumulative plant cane and first ratoon crops with respect to five commercial controls. The families differed significantly and the between families variation was significantly higher than the within family variation for most traits. At the seedling stage, narrow-sense heritability ranged from low to moderate (0.16-0.62) but improved in the replicated trial (0.67-0.95). Three univariate methods were examined: the predicted proportion of elite genotypes (PROB), the family mean (MEAN), and the observed proportion of elite genotypes that transgress set values (OBS). There were highly significant positive correlations among the three predictive statistics indicating their reliability in predicting potential of crosses (r = 0.58-1.00). The best univariate predictors were MEAN and PROB for BP and PY at the seedling stage. Family ranking, based on BP at the seedling stage, is a reliable predictor of PY at the 3rd clonal stage. Two bivariate methods, sum of ranks (RANK) and the observed frequency of genotypes that transgress set targets simultaneously (FREQ) were equally useful in identifying the desirable crosses (r = -0.77-0.93). Highest correlation coefficients between the RANK and FREQ statistics at the seedling stage were obtained for BP-PY (-0.92**) and BP-SNO (-0.93**). In addition, the multivariate RANK statistics, based on simultaneous ranking for all five characters at the seedling stage, was reliable in identifying the best three crosses that ultimately produced 82per cent of elite genotypes for testing in final stages of selection. | |
sugarcane breeding crossing cross prediction prediction statistics families varieties genotypes genetic variance heritability | |
Mauritius | |
Cane breeding and genetic improvement | |
Breeding: Crossing | |
2007-08-13 | |
En | |
LIB | |
CAT | |
PB |