부산대학교 도서관

Low spring temperatures are one of the main limiting factors for maize (Zea mays L.) growth along the European Atlantic coast. Several breeding programs have been performed to obtain cold-tolerant maize genotypes, but the few cold-tolerant inbreds and hybrids available need further improvements for cold tolerance and agronomic performance. The objective of this study was to identify cold-tolerant maize populations with favorable alleles to improve cold tolerance and agronomic performance in early sowing of two cold-tolerant hybrids. The parental inbred lines of two cold-tolerant hybrids were crossed to nine cold-tolerant populations. Tests were performed in a cold chamber and in the field for 2 yr at two locations. The populations Rojo de Tolosa and Puenteareas were the most promising sources of new favorable alleles for transferring cold tolerance to the hybrids EP80 x F7 and EP80 x Z78007, respectively. The populations Puenteareas and Silver King were the most outstanding donors to improve the agronomic performance of EP80 x F7 and EP80 x Z78007, respectively. Some improved versions of the cold-tolerant inbred parents could be developed from crosses between F7 or Z78007 and Puenteareas; alternatively, Rojo de Tolosa or Silver King could be used as donors of favorable alleles, but the simultaneous improvement of yield and cold tolerance is not straightforward.