The flowers of Rhododendron ponticum attract bees, hoverflies, and butterflies. These insects pollinate the flowers which can then produce between three and seven thousand seeds. When the average number of flowers per bush is taken into account, each bush can produce several million seeds every year. The seeds produced are then spread by either wind or water, and they can be carried up to 100 meters away from the bush.

     These seeds are a very important part to the success of Rhododendron ponticum. Since the flowers produce so many seeds, it helps the species to quickly spread and succeed. Also, the seeds can be dormant for several years and still be viable.

     Rhododendron ponticum goes through an alteration of generations. This means that there is both a diploid (2N) and a haploid (N) multicellular stage. Haploid refers to having one set of chromosomes while diploid refers to having two sets of chromosomes.
     1. During this process, the diploid sporophyte goes through meiosis and produces haploid spores.
          a. In the flower’s male
          parts, called the anthers,
          are microsporocytes which
          are diploid. The
          microsporocytes (2N) go
          through meiosis and
          produce microspores (N).
          b. The flower’s female
          parts are carpels which
          include the stigma, style,
          ovary, and ovule. Inside
          the ovule is a
          megasporocyte which is
          diploid. The
          megasporocyte (2N) goes     
          through meiosis to
          produce megaspores (N).

2. The spores then undergo mitosis and grow into haploid gametophytes.
          a. In the male parts, the    
          microspores (N) go through
          mitosis to produce the      
          microgametophyte (N).
          b. In the female parts, the megaspore (N) goes through mitosis to produce the
          megagametophyte (N).
               · Sperm (N) come from the microgametophyte (N).
               · The egg (N) comes from the megagametophyte (N).

The gametes (sperm and egg) then fuse together during fertilization to produce a diploid zygote.

The cycle completes when then zygote undergoes mitosis and grows into a diploid sporophyte, and the process repeats.


Interactions involving Rhododendron ponticum