The prediction of heterosis based on the phenotypic distance of sweet maize parental lines

Abstract

A relatively narrow genetic background, limited sources of germplasm that satisfies commercial standards, poorly defined heterotic groups, as well as a small span for yield and quality estimation are reasons for the modest improvement in sweet corn yields in comparison with standard grain quality maize. Therefore, any additional information could be of a great use. Based on the phenotypic characterization according to UPOV descriptor, phenotypic distances of 14 ZP sweet corn inbred lines were evaluated, and clustering was performed. Grouping showed that 9 out of 11 hybrids obtained by crossings of 14 sweet corn inbred lines had parental lines assigned to different subclusters. Two hybrids whose parental components belonged to the same subcluster had some important specific traits, such as early maturity (ZP 111su), and super-sweet germplasm (ZP 407su). Results obtained by this procedure could be of great assistance in the process of selecting parental lines for the future crossings.

Relativno uska genetička osnova, ograničeni resursi germplazme koja zadovoljava komercijalne standarde, loše definisane heterotične grupe kao i kratko vreme koje je na raspolaganju za procenu prinosa i kvaliteta su razlozi slabijeg unapređenja prinosa hibrida kukuruza šećerca u poređenju sa hibridima standardnog kvaliteta zrna. Stoga svaka dodatna informacija može da bude od velikog značaja. Na osnovu karakterizacije po UPOV deskriptoru urađena je klaster analiza 14 ZP linija kukuruza šećerca. Grupisanje je ukazalo da su se roditeljske linije 9 od 11 hibrida grupisale u različite podklastere. Dva hibrida, čije su se roditeljske linije grupisale u isti klaster su nosioci nekih specifičnih karakteristika kao što je ranostasnost (ZP 111su) i super-slatka germplazma (ZP 407su). Rezultati grupisanja dobijeni ovom procedurom mogu biti od velike pomoći pri izboru roditeljskih linija za buduća ukrštanja linija šećerca.