Variation in starch physicochemical properties of rice with different genic allele combinations in two environments

Abstract

The starch physicochemical properties were investigated in 16 different rice accessions with different combinations of Wx, SSIIa and FLO2 alleles harvested in two environments. FLO2, Wx and SSIIa alleles and their interaction significantly affected the starch properties. The values of apparent amylose content (AAC), gel hardness (HD), pasting temperature (PT), gelatinization temperature (GT), enthalpy of gelatinization (ΔHg), enthalpy of retrogradation (ΔHr) and percentage of retrogradation (R%) in the rice with FLO2 allele were slightly larger than those with flo2 mutant allele. The Wx × SSIIa interaction had a significant effect on breakdown (BD), setback (SB), ΔHr and R%. With Wxb allele, the influence of SSIIa allele on GT was slightly greater than that with Wxa. With SSIIa GC allele, Wxb played a greater role in the increase of PT than Wxa, but the reverse was found with SSIIa TT allele. The FLO2 × Wx interaction significantly affected the AAC, cold paste viscosity (CPV), hot paste viscosity (HPV), PT, HD, peak temperature (Tp), conclusion temperature (Tc) and ΔHr. FLO2 × SSIIa combination significantly affected AAC, HPV, CPV, Tc and ΔHr. This study will help us to further understand the roles of these starch synthesis-related important genes in regulating rice quality and could be better utilized in molecular breeding.