About Ghosts, Corpses and Witches

Monotropastrum humile CourtesyWikipedia

Halloween  being just a few  days away  this is an ideal time to talk about ghosts, corpses and witches, but among  the Flora.

Ghost flowers? Yes, these are actually beautiful   translucent  blossoms on  pearly white  stalks.   These plants  lack  chlorophyll  and that explains their deathly pallor.   No  chlorophyl means no need for sunlight and  hence they flourish in the darkest corners of  forests, adding to their ghostly glow. Also called monotropes, there are  several closely related varieties and all  belong to  the  monotropoideae  subfamily. These are plants alright, but    without  chlorophyll and access to sunlight how do they fix their dinner? How do they get energy to survive?   

Plants with chlorophyl are autotrophs. Auto means self and trophos means food/nurishment.   They generate their own food through photosynthesis. Heterotrophs  depend on others for food.   The Monotropoideae are mycoheterotrophs, as they depend on mykos   (fungi) for food.  To put it simply  ghost plants  thrive as  parasites on fungi.  This fungal dependence is  highly specific  with different plant genera associating with different groups of  fungi. Such  specialized associations are a crucial factor for  their survival and distribution. 

Fungi, on their part  are indeed a hardworking lot. They  form  underground networks (mycorrhizal networks) to forage through the soil to collect phosphorous and other mineral nutrients.  They then trade these with  trees in exchange for sugars, a  win-win situation for both partners. The  ghost plants stick on to the fungi and  appropriate part of the fungal food reserve.    An abundance of ghost plants indicate   robust fungal network underneath and fertile soil.  The ability of  ghost plants  to exploit the tree-fungi food chain is considered  an ingenious adaptation and evolutionary strategy. 

Rafflesia arnoldii  courtesy : wikipedia

Corpse lilies are so named ,because of their repulsive stench of rotten flesh.  Belonging  to the  Rafflesiaceae    family  there are at least 40 varieties and they produce  world’s largest flowers.  Among them    Rafflesia arnoldii  is one of the   National Flowers of Indonesia.  The Flower's foul smell  attracts swarms of carrion flies which  facilitate  pollination.  There are no known uses  and not much research has been done on these plants/flowers.   

Striga Plant Courtesy: Randy Westbrooks Wikipedia 

The ghost and Corpse plants  are parasitic  they  do steal food from their  hosts  but  never cause any  harm 

In  Latin  Striga,  means witch and that is the genus name for witchweeds.    There are at least 30 species  and they all belong to the Orobanchaceae family.  Though  innocuous looking, striga  is  a killer weed and  a major threat to  crops like sorghum, corn, sugarcane and rice.  It attaches itself  to the roots of the host and  sucks off   all the nutrients and water.  As a result the host plant wilts and dies.  Striga's  seed pods can  hold  billions  of microscopic seeds which can hibernate in the soil for decades. 

 

REFERENCES:

1. A review on subfamily  Monotropoideae (Ericaceae) for Thailand 

2. Developmental origins of the world’s largest flowers, Rafflesiaceae  

3. Witchweed (Striga Asiatica)an overview of management strategies in the USA 

4. The genus Striga : a witch profile 

 

TAIL PIECE

There is a popular legend  among  the Cherokee Indian  tribe in North America. They believe that when friends and relatives quarrel  ghost plants flourish in their neighborhood. Because   once upon a time  two chieftains had a disagreement, they met to settle the issue, but instead  they smoked tobacco pipes and continued to  quarrel   stubbornly  for 7days.    This  annoyed the  Spirit and  he turned them into  ghostlike flowers with drooping heads  and  long stems.