Reproductive biology of three commercially valuable Santalum species: development of flowers and inflorescences, breeding systems, and interspecific crossability

Abstract

Santalum (sandalwood) spp. are hemiparasitic trees, the heartwood of which produces valuable aromatic oil. There appears to be a significant commercial opportunity for establishment of a planted sandalwood resource. However, lack of basic biological knowledge is one constraint on such development. The study reported here addresses one such constraint. Controlled pollination using 13 genotypes of Santalum lanceolatum was undertaken to elucidate (i) selfincompatibility (ii) intraspecific cross-compatibility in the species, and (iii) interspecific cross-compatibility with S. album and S. austrocaledonicum. S. lanceolatum may be considered to have a facultative allogamous (incomplete outbreeding) breeding system. This study found variation between genotypes in the level of putative self-incompatibility: some (20%) were found to set seed following self-pollination, while the remaining 80% had no seed development with such pollinations. However, a significantly greater proportion of genotypes developed seed following intraspecific cross-pollination (62%) compared with self-pollination (20%). While total geographic isolation and significant morphological divergence exists between S. lanceolatum with each of S. album and S. austrocaledonicum this study found no indication of reproductive barrier(s) between them, indicating potential for use of interspecific hybridization in genetic improvement, but also suggesting the potential of undesirable gene flow between native and introduced species.

The effects of population size on genetic parameters and mating system of sandalwood in Gunung Sewu, Indonesia

“…Clonality event occurred when most of off-springs in population were derived from a genetically identical individuals (Warburton et al, 2000;Lhuillier et al 2006;Dani et al, 2011). Previous researches documented pollen limitation due to less pollen production (Sindhu-Vereendra and Anantha-Padmanabha, 1996; Tamla et al, 2012) and male sterility (Warburton et al, 2000). Sandalwood's sexual reproductive success was also very low, ranging from 0.03% in natural population to less than 20% in ex situ plantation (Ratnaningrum and Indrioko, 2014).…”

“…However, to date, only very limited studies have been conducted in correlating the geographical variation to the genetic diversity and mating systems of sandals group (Harbaugh and Baldwin, 2007;Rao et al, 2007;Dani et al, 2011). Such works were mostly conducted in Southern India (Sindhu-Vereendra and AnanthaPadmanabha, 1993;Brand, 1994;Suma and Balasundaran, 2003;Rao et al, 2007;Dani et al, 2011), Western Australia (Warburton et al, 2000;Byrne et al, 2003;Tamla et al, 2012), insular Pacific (Lhuillier et al, 2006), and New Caledonia (Bottin et al, 2007) for more than couple of decades. However, only recently have such comparative analyses been extended to sandals of other regions.…”

Variasi Karakter Pembungaan Antar Varian dan Ras Lahan Cendana Sepanjang Gradien Geografis di Gunung Sewu

“…Perbedaan struktur populasi (Byrne et al 2003;Bottin et al 2007;Dani et al 2011) dan struktur reproduksi (Rughkla et al 2006;Warburton et al 2000;Rao et al 2007;Herlihy & Eckert 2005;Barrett et al 2006;Tamla et al 2012) dapat berakibat pada berbedanya sistem perkawinan dan proses reproduksi. Hal serupa terjadi pada Santalum album di India (Rughkla et al 2006), S.…”

“…Barat (Tamla et al 2012) dan S. lanceolatum di Victoria (Warburton et al 2000), yang mengalami kegagalan pembuahan dikarenakan perbedaan struktur organ reproduksi pada beberapa varian cendana. (Warburton et al 2000;Byrne et al 2003;Rughkla et al 2006;Tamla et al 2012), Kepulauan Pasifik (Lhuillier et al 2006) dan New Caledonia (Bottin et al 2007) selama lebih dari dua dekade terakhir.…”

“…(Warburton et al 2000;Byrne et al 2003;Rughkla et al 2006;Tamla et al 2012), Kepulauan Pasifik (Lhuillier et al 2006) dan New Caledonia (Bottin et al 2007) selama lebih dari dua dekade terakhir. Namun di tempat yang dipercaya sebagai center of origin cendana, yaitu Indonesia, penelitian masih sangat terbatas, baik di Indonesia bagian Tenggara (Brand 1994;Herawan et al 2014; maupun, terutama, Indonesia bagian barat (Ratnaningrum & Indrioko, 2014, 2015 Parameter fenologi pembungaan meliputi (1) Gambar 1.…”