The application of Tukey’s mean difference (Tukey’s HSD) for identification of local genetic sources of corn in selecting prospective parental lines

Abstract

Extensive use of corn hybrids in Indonesia started in 1980 became expensive to farmers. In fact, the hybrids became obsolete and were replaced with the new ones. The obsolete hybrids, however, expressed superior traits toward detrimental hindrances in situ. The traits were identified, the obsolete hybrids were worthy to select for being local genetic sources (LGS) in a corn breeding program. The research was done to identify the LGS collected from Padang, Palembang, Jogjakarta, West Kalimantan and Lampung. In 2018 the LGS were planted in two rows and open-pollinated among themselves. The seeds were harvested separately to make female lines. A synthetic line was made by mixing 100 seeds of each female line. In 2019 the six lines: five female and one synthetic, and Pioneer36 (P36) F1-hybrid as control were planted in a randomized complete block design with 3 replicates. The data were collected for traits: plant height, leaf number plant−1, time to tasseling, time to silking, ear length, ear diameter, 100 seed weight and seed yield m−2. The data were variance-analysed and Tukey’s HSD was applied to separate and group the lines. A dendrogram was constructed to decide lines suitable to recombine. The result indicated that the Padang, Palembang, Lampung and Synthetic lines could be used as the male parents to recombine with the Jogjakarta and West Kalimantan lines. The Tukey’s HSD and dendrogram statistics could be useful to identify line superior and pairing appropriate lines as parents in a breeding program.