The ‘True‐to‐Type’ Kopyor Coconut ( <scp> <i>Cocos nucifera</i> </scp> L.) Hybrid (KSYD × KST) Seedlings Revealed by Morphological and Molecular Analyses

ABSTRACT Kopyor coconut is one of the most valuable crops in Indonesia because of its price, more than 10 times higher compared to normal nuts. Up to now, no effort has been reported on improving kopyor coconut quality using either conventional or modern biotechnology approaches. This research aims to produce F1 hybrid kopyor and to analyse the F1 hybrid based on morphological and molecular levels. The production of true‐to‐type kopyor hybrid (KH) seedlings has been accomplished using a conventional breeding programme between female Kopyor Sinumpur Yellow Dwarf (KSYD) and male Kopyor Sinumpur Tall (KST). Eleven months after hand‐pollination, the KH fruits were harvested; the embryos were then isolated and cultured through the embryo rescue technique for another 8 months, followed by acclimatization and nursing steps for another 10 months until the seedlings were ready for field planting. Morphological analysis of 47 KH seedlings compared to KSYD and KST seedlings showed that 40 seedlings had green or brown petioles and 7 seedlings had yellow petioles. KH seedlings also showed that the length of shoots, number of leaves, length and width of leaves, and diameter of stems were similar to KST seedlings but significantly higher compared to KSYD seedlings. The molecular comparison of the KH seedlings to the female and male parents has also been analysed using 12 CIRAD simple sequence repeat (SSR/microsatellite) primers. A single SSR primer, CnCIR A9, showed five specific alleles, that is, 85‐bp allele only found in KSYD and 95‐, 127‐, 234‐ and 270‐bp alleles only found in KST. The KH seedlings can be categorized into four groups: a group with all five alleles, both tall and dwarf alleles (18 seedlings); a group with dwarf and part of tall alleles (23 seedlings); a group with all four tall alleles only (3 seedlings); and a group with the dwarf allele only (3 seedlings). Interestingly, seven KH seedlings with yellow petioles were included in the final group. From these results, both morphological and molecular analyses can be used for early hybrid verification in the KC breeding programme.