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Proceedings of International Conference on Climate Change, Biodiversity and Ecosystem Services for the Sustainable Development Goals : Policy and Practice 27-29 June 2016 at the Sirindhorn International Environmental Park, Cha-am, Phetchaburi, Thailand

2016).  Natural  hybridization  is  common  in  plants  and  has  been  observed  with  mangrove  species.  Putative  hybrids  have  been  reported  within  the  major  genera  of  Rhizophora,  Sonneratia,  Lumnitzera  and  Brugueira  (Tomlinson,  1986;  Duke  and  Ge,  2001).  To  identify  natural  hybrids  of  the  mangroves  Rhizophora  apiculata,  R.  mucronata  and  R.  stylosa  in  Malaysia  Ng  et.  al.  (2013)  and  Ng  and  Smidt  (2013)  used  single  nucleotide  polymorphisms  (SNPs)  from  nuclear  genomes. In  Thailand  one  putative  hybrid  of  Rhizophora  spp.  was  discovered  at  Sirindhorn  International  Environment  Park  (SIEP),  Cha-am,  Phetchaburi  Province  (12°42′  17.57"N;  99°57′  43.67"E).  At  the  time  of  discovery  this  hybrid  had  the  following  attributes:  height  9.0  m;  Girth above  uppermost  prop  roots  40.0  cm  with  prop roots  of  20  cm  in  girth.  Rhizophora  mucronata  and  R.  apiculata  trees  near  this  hybrid  were  only  5.8  m  in  height.  While  leaf  size  of  the  hybrid  did  not  differ  from  those  of  parental  types,  some  colour  pigmentation  differences  were  observed  near  the  base  of  the  midrib:  here  R.  mucronta  was  light  green,  R.  apiculata  was  red  and  the  putative  hybrid  displayed  a  much  lighter  red  pigmentation.  Likewise,  differences  were  displayed  in  flower  attributes;  those  of  R.  apiculata  were  paired  on  short  stalks;  R.  mucronata  flowers  were  organized  in groups  of  3-8  flowers  on  long  stalks.  Those  of the  putative  hybrid  were  paired  with  a  2-3  cm  stalk  (Figure  1). Interestingly,  some  hybrid  prop  roots  were  oriented  on  angles  greater  than  90  degrees  from  the  main  trunk  in  contrast  to  those  of  R.  apiculata  which  displayed  more  typical   angles   of   90  degrees   or   les s .  Additionally,  the  hybrid  produced  many  branches  within  the  prop  root  zone  (Figure  2). Based  on  these  observat ions  of  morphological  attributes  the  aim  of  this  study  was  to  seek  evidence  that  this  hybrid  was  in  fact  a  putative  hybrid  of  two  Rhizophora  species  using  SNPs  from  nuclear  and  chloroplast  regions.  Fig.2  Prop  roots  of  hybrid  mangrove Fig.1  Leaves  and  flowers  of  putative  hybrid  (above),  Rhizophora  mucronata  (left)  and  Rhizophora  apiculata  (right) Proceedings  of  the  International  Conference  on  Climate  Change,  Biodiversity  and  Ecosystem  Services  for  the 53 Sustainable  Development  Goals  (SDGs):  Policy  and  Practice  27-29  June  2016,  Cha-am,  Phetchaburi,  Thailand


Proceedings of International Conference on Climate Change, Biodiversity and Ecosystem Services for the Sustainable Development Goals : Policy and Practice 27-29 June 2016 at the Sirindhorn International Environmental Park, Cha-am, Phetchaburi, Thailand
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