Comparison of biplot analysis and Kang's YSi statistic in estimating maize hybrids stability

Abstract

Integration of mean yield and stability evaluation into a single analysis is practical for maize hybrids recommendation and approval in multi-environment trials. The objective of this study was (i) to investigate grain yield performance and stability of 21 experimental maize hybrids via the use of the Kang's yield-stability statistics (YSi) and via the sites regression biplot (GGL) from multi-location trial conducted in Serbia; and (ii) to determine if hybrids yield stability was influenced by the linear effect of an environmental index. Hybrid main effect was highly significant and captured 9% of total sum of squares. Hybrid × location interaction was highly significant and accounted for 8.1% of the total sum of squares. Heterogeneity caused by environmental index was statistically non-significant. The same genotypes were recognized as stable by YSi and GGL biplot, but we recommend the sites regression biplot as more informative and precise tool for simultaneous hybrids mean performance and stability estimation.

Istovremena procena prinosa i stabilnosti prinosa na osnovu rezultata iz multi-lokacijskih ogleda ima veliki značaj u preporuci hibrida kukuruza. Cilj ovog istraživanja bio je da se ispita (i) prinos i stabilnost prinosa eksperimentalnih hibrida kukuruza pomoću Kangove statistike stabilnosti (YSi) i metodom SREG GGL biplot analize, na osnovu podataka iz multi-lokacijskih ogleda u Srbiji, i (ii) da li su linearni efekti indeksa spoljašnjih sredina uticali na stabilnost hibrida. Glavni efekti genotipa (hibrida) bili su visoko značajni i obuhvatali su 9% od ukupne sume kvadrata. Interakcija hibrid × lokalitet je takođe bila visoko značajna i obuhvatala je 8,1% od ukupne sume kvadrata. Heterogenost uslovljena razlikom između spoljašnjih sredina bila je statistički neznačajna. Na osnovu rezultata obe analize isti genotipovi su izdvojeni kao stabilni ali je prednost na strani SREG modela kao preciznijeg i informativnijeg.