The Korean Journal of Crop Science ISSN:0252-9777(Print) 2287-8432(Online) 한국작물학회지

Maize grain quality can be improved by raising lysine content, which is an essential amino acid present in insufficient quantities in normal maize. Maize varieties with such modifications are known as quality protein maize (QPM). To date, no Korean maize cultivars contain high amounts of lysine. To introduce quality protein maize to Korean cultivars, we crossed QPM CIMMYT maize lines (CML) with KS140, an elite inbred line used as a parent of several cultivars such as ‘Gangdaok’ and ‘Pyeonganok’. We analyzed the phenotypic characteristics of F₁ plants as well as the protein contents, amino acids, and fatty acids profiles of the self-pollinated seeds of the F₁ hybrids, and evaluated the feasibility of CML as a source of QPM. Days to anthesis of the CML ranged from 78 to 90 days after planting (DAP), whereas a range of 81~87 was recorded for F₁ hybrids. The average days to anthesis was 85 for KS140, CML, and the F₁ hybrids. The protein content of the CML was measured to be between 9.1 and 12.1%, with the highest and lowest values being recorded in CML153 and 191, respectively. The F₁ hybrids had protein contents of 9.1~11.1%, and the highest content was observed in KS141/CML188. The fatty acids profiles were very similar across all analyzed maize samples, and linoleic acid (C18:2) composed the greatest proportion. Glutamic acid made up the largest proportion of amino acids in all maize samples. Lysine composition was highest in CML155 (6.92% of all amino acids), with an average composition of 4.83% across the CML. In contrast, KS140 showed a lysine content of 2.51%. In F₁ hybrids, the average lysine composition was 3.46%, and KS140/CML164 (4.18%) and KS140/CML163 (4.99%) contained more lysine than either parent. Taken together, these results indicate that CML could become promising QPM sources to improve grain quality in Korean maize cultivars.