ARS | Publication request: Breeding system and its consequence on fruit set of a rare sand dune shrub Eremosparton songoricum (Fabaceae: Papilionoideae): implications for conservation

Submitted to: Journal of Arid Land
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 24, 2011
Publication Date: September 27, 2011
Citation: Zhang, D., Shi, X., Wang, J., Liu, H., Gaskin, J.F. 2011. Breeding system and its consequence on fruit set of a rare sand dune shrub Eremosparton songoricum (Fabaceae: Papilionoideae): implications for conservation. Journal of Arid Land. 3(4):231-239.

Interpretive Summary: The breeding system and fruit set of Eremosparton songoricum, a rare shrubby legume occurring in moving or semi-fixed sand dunes of Central Asian deserts, were examined. The results showed that E. songoricum exhibits a mixed mating system. It is self-compatible, but depends strictly on pollinators to set fruits. Only two effective pollinators were detected and they triggered the specialized pollination mechanism The results explained the rarity of the species due to its breeding system, and will assist to develop suitable conservation strategies in severe desert environments.

Technical Abstract: The breeding system and its consequence on fruit set of Eremosparton songoricum (Litv.) Vass., a rare shrubby legume occurring in moving or semi-fixed sand dunes of Central Asian deserts, were examined by manipulative experiments and observational studies in natural populations during the period of 2007–2009. The results showed that E. songoricum exhibits a mixed mating system. It is self-compatible, but depends strictly on pollinators to set fruits. Only two effective pollinators were detected and they triggered the specialized pollination mechanism (a ‘brush type’ and ‘tripping mechanism’). Geitonogamy becomes predominant in natural populations, because (74.5±1.3)% of visiting activity happened within or between inflorescences and (24.3±1.4)% occurred between ramets. As a result, inbreeding depression caused by geitonogamous selfing inevitably happened under natural conditions, showing 2.36 times less fruit set than was achieved by hand cross-pollination. The results explained the rarity of the species due to its breeding system, and will assist to develop suitable conservation strategies in severedesert environments.