Australian Journal of Botany Australian Journal of Botany Society
Southern hemisphere botanical ecosystems

Reproductive biology of Melaleuca alternifolia (Myrtaceae) 2. Incompatibility and pollen transfer in relation to the breeding system

L. Baskorowati A E , M. W. Moncur B , S. A. Cunningham C , J. C. Doran D and P. J. Kanowski A
+ Author Affiliations
- Author Affiliations

A The Fenner School, Australian National University, Canberra, ACT 0200, Australia.

B 19 Sherwin Place, Melba, ACT 2000, Australia.

C CSIRO Entomology, Clunies Ross Street, Black Mountain, Acton, ACT 2601, Australia.

D Australian Tree Seed Centre, CSIRO Plant Industry, PO Box 1600, Canberra, ACT 2601, Australia.

E Corresponding author. Email:

Australian Journal of Botany 58(5) 384-391
Submitted: 8 February 2010  Accepted: 31 May 2010   Published: 21 July 2010


The onset of stigma receptivity in Melaleuca alternifolia (Maiden & Betche) Cheel was evaluated by observing pollen-tube growth and seed set following controlled pollination. Pollen-tube numbers in the style, following controlled pollinations, increased from Day 1 to Day 6, then declining rapidly. The stigma was most receptive during Days 3–6, and still receptive at low levels as early as shortly after anthesis and as late as 10 days after pollination. The present study found that individuals of M. alternifolia differed in their degree of expression of self-incompatibility. Artificial self-pollination, with emasculation, in several families resulted in complete self-incompatibility, with no capsule retention. The microscopic observation of pollen-tube development revealed a mechanism of self-incompatibility in M. alternifolia. A self-incompatibility system operates in the style, although a few self-pollen grains are capable of germinating and producing pollen tubes. It also appears that late-acting self-incompatibility mechanisms discriminate against self-pollen tubes when they descend to the ovary. Artificial cross-pollination of selected parents produced seed with greater germination capacity and seedlings that grew faster than the corresponding open-pollinated seed and seedlings from the same parent. Freeze-dried pollen stored at -18°C maintained viability (22%) over 1 year of storage. This finding will allow greater flexibility in undertaking controlled pollinations, because stored pollen can be substituted for fresh pollen when insufficient quantities are available from new-season flowers. A wide variety of insects was observed visiting the flowers of M. alternifolia, and capsule set was high even in bags that excluded flower visitors greater than 2 mm. Thrips species seem likely to be important pollinators of this species because they are small and were abundant inside and outside of exclusion bags, although several other insect species such as bees, flies and wasps were also identified as frequent floral visitors.


We acknowledge the Australian Centre for International Agricultural Research for awarding a John Allwright Post Graduate Fellowship to the first author. We also thank ANU’s Dr Cheng Huang for assistance with the fluorescence microscopy work, and Dr Emlyn Williams for statistical advice and analyses; and CSIRO Entomology’s Dr Laurence Mound and Mr Kim Pullen for insect identifications. Additional field support and data were provided by Gary Baker (NSW DII), Paul Warburton (CSIRO) and Geoff Davis (GR Davis P/L). Infrastructure support came from ANU, CSIRO, and NSW DII through the RIRDC/ATTIA tea-tree breeding program.


Baker GR , Doran JC , Williams ER , Southwell IA (2007) ‘Breeding and cloning tea tree for greater profitability 2001–2006.’ RIRDC Publication No. 07/142. (RIRDC: Canberra)

Barlow BA , Forrester J (1984) Pollen tube interaction in Melaleuca. In ‘Pollination 84’. (Eds EG Williams, RB Knox) pp. 154–160. (The School of Botany, University of Melbourne: Melbourne)

Baskorowati L (2006) Controlled pollination methods for Melaleuca alternifolia (Maiden & Betche) Cheel. ACIAR Technical Report 63, ACIAR, Canberra.

Baskorowati L (2008) Reproductive biology of Melaleuca alternifolia (Maiden & Betche) Cheel. PhD Thesis, The Australian National University, Canberra.

Baskorowati L, Moncur M, Doran J, Kanowski P (2010) Reproductive biology of Melaleuca alternifolia (Maiden & Betche) Cheel 1. Floral development. Australian Journal of Botany 58, 000–000.

Beardsell DV, O’Brien SP, Williams EG, Knox RB, Calder DM (1993) Reproductive biology of Australian Myrtaceae. Australian Journal of Botany 41, 511–526.
CrossRef |

Butcher PA, Bell JC, Moran GF (1992) Patterns of genetic diversity and nature of the breeding system in Melaleuca alternifolia (Myrtaceae). Australian Journal of Botany 40, 365–375.
CrossRef |

Ditlevsen B (1985) Controlled crossing systems and designs. Forest Tree Improvement, FAO Forestry Paper 20. FAO, Rome, pp. 148–159.

Doran JC , Moran GF (2002) Development of DNA markers for breeding of tea tree. Unpublished report for the Rural Industries Research and Development Corporation, CSIRO, Canberra.

Doran JC , Baker GR , Southwell IA (2002) ‘Improving Australian tea tree through selection and breeding (1996–2001).’ RIRDC Publication No. 07/017. (RIRDC: Canberra)

Eldridge KG , Davidson J , Harwood CE , Van Wyk G (1994) ‘Eucalypt domestication and breeding.’ (Clarendon Press: Oxford)

Griffin AR, Ching KK, Johnson KW, Hand FC, Burgess IP (1982) Processing Eucalyptus pollen for its use in controlled pollination. Silvae Genetica 31, 198–203.

Hodgson LM (1976) Some aspects of flowering and reproductive behaviour in Eucalyptus grandis (Hill) Maiden. 1: Flowering, controlled pollination methods, pollination and receptivity. South African Forestry Journal 97, 18–28.

Kartikawati NK (2005) Tingkat inkompatibilitas bersilang sendiri pada tanaman kayu putih (the level of self-incompatibility of Melaleuca cajuputi subsp. cajuputi). Jurnal Penelitian Hutan Tanaman 2, 141–147.

Martin FW (1959) Staining and observing pollen tubes in the style by means of fluorescence. Stain Technology 34, 125–128.
CAS | PubMed |

Moncur MW, Boland DJ (1989) Floral morphology of Eucalyptus melliodora A.Cunn. ex Schau and comparisons with other eucalyptus species. Australian Journal of Botany 37, 125–135.
CrossRef |

Mound LA (2005) Thysanoptera: diversity and interactions. Annual Review of Entomology 50, 247–269.
CrossRef | CAS | PubMed |

O’Brien SP (1994) Pistil structure and pollen tube pathways in Leptospermum myrsinoides and L. continentale (Myrtaceae). Annals of Botany 73, 225–230.
CrossRef |

O’Brien SP, Calder DM (1993) Reproductive biology and floral phenologies of the sympatric species Leptospermum myrsinoides and L. continentale (Myrtaceae). Australian Journal of Botany 41, 527–539.
CrossRef |

Potts BM , Gore P (2000) Reproductive biology and controlled pollination of Eucalyptus – a review. In ‘Symposium on hybrid breeding and genetics, Noosa, Qld’. (Queensland Government, Queensland Department of Primary Industry and Queensland Forestry Research Institute: Noosa, Qld)

Pound M, Wallwork MAB, Potts BM, Sedgley M (2002) Self-incompatibility in Eucalyptus globulus ssp. globulus (Myrtaceae). Australian Journal of Botany 50, 365–372.
CrossRef |

Pound M, Wallwork MAB, Potts BM, Sedgley M (2003) Pollen tube growth and early ovule development following self- and cross-pollination in Eucalyptus nitens. Sexual Plant Reproduction 16, 58–69.
CrossRef |

Rosseto M, Slade RW, Baverstock PR, Henry RJ, Slee LS (1999) Microsatelite variation and assessment of genetic structure in tea tree (Melaleuca alternifolia – Myrtaceae). Molecular 8, 633–643.

Sedgley M , Griffin AR (1989) ‘Sexual reproduction of tree crops.’ (Academic Press: London)

Sedgley M, Smith RM (1989) Pollen receptivity and pollen tube growth in relation to the breeding system of Eucalyptus woodwardii (Symphyomyrtus: Myrtaceae). Annals of Botany 64, 21–31.

Terry I, Walter GH, Moore C, Roemer R, Hull C (2007) Odor-mediated push-pull pollination in cycads. Science 318, 70.
CrossRef | CAS | PubMed |

Williams ER , Matheson AC , Harwood CE (2002) ‘Experimental design and analysis for tree improvement.’ 2nd edn. (CSIRO Publishing: Melbourne)

Rent Article (via Deepdyve) Export Citation Cited By (1)