Crops Should Get High On Magic Mushrooms!

What do bacteria, fungi, and cyanobacteria all have in common?

They are all microorganisms currently being researched as possible biofertilizers. 

More specifically, scientists are attempting to isolate phosphate-solubilizing microorganisms. They hope that these microorganisms will be able to mobilize the insoluble phosphate found in our crop soil.

Ok, that sounds easy enough. So what’s the holdup?

Microorganisms are rare and only a few of them can actually mobilize phosphate under natural soil conditions.  Most phosphate-solubilizing microorganisms demonstrate their phosphate-solubilizing abilities in the lab only, placing current research in this field at a standstill.

“Moreover, a main problem, indeed, is connected with the fate and activity of introduced microorganisms,” writes biotechnologist Chunqiao Xiao. “Normally, many isolates present high phosphate solubilizing capability in growth medium, but when they are inoculated to natural conditions, they often exist in a form characterized by non-growth and/or low phosphate solubilizing capability.”

Xiao and his colleagues decided to concentrate on possible phosphate-solubilizing fungi recently found in China’s phosphate mines. They were mainly interested in these specific mines because they had never been researched.

They collected samples for isolation  from phosphate mines in the Hubei province. The best three fungal isolates were selected based on the content of soluble phosphorus released in culture medium (shown in the figure below). The fungal isolates were grown on a variety of phosphorus sources to monitor their solubilizing abilities. The isolates were then added to wheat crops in natural soil conditions for growth analysis.

Before I get into the results of this paper, I cannot help but comment on the method section. The authors did not give too many details regarding the specifics of the conducted research, but they provided the necessary information. Having read hundreds of scientific papers myself, I can honestly say that this quality of writing is quite a rare feat.

Xiao and his team succeeded in isolating and characterizing three new phosphate-solubilizing fungi from these mines. The fungi demonstrated the ability to mobilize phosphate from its insoluble form to its soluble form for plant uptake. They also produced organic acids to decrease the pH of their surroundings to further solubilize phosphate (graph below). 

The most exciting finding of this experiment however was the increase in wheat crop growth when these fungi isolates present in the soil (shown in table below). In addition, the results were observed outside of a lab setting, leaving very little debate that these specific fungi isolates will be future biofertilizers. 

However, this paper does make a key experimental error. Xiao only used rock phosphate as a substrate for the isolated fungi. Ideally, crops would be fertilized with a microorganism capable of mobilizing phosphate from all types of phosphate substrates. It is these slight oversights that distinguish a good research paper from a great research paper.

So why should we care about this type of research anyway?

Well, wheat is a very important crop. Global wheat consumption is 101 kg per capita, and predicted to increase by 10% over the next decade.

We need to develop techniques to help wheat crops flourish if we plan on feeding our ever-growing world population. In conjunction with the decline of non-renewable phosphate,  investment in this type of research is not debatable.

Umm, that’s it right? We add some microorganisms to our crops, decrease our fertilizer inputs, and call it a day. 

Well…

Call me a pessimist if you will but people lack the dedication and integrity necessary to put this type of research into reality. We have no problem throwing millions of dollars at research because it helps us sleep at night and feel a little less guilty about our consumptive lifestyles.  

However, people have proven time and again that they are completely incapable of putting even the most innovative research into action. We know smoking causes lung cancer. We know that solar energy is the right replacement for fossil fuels. Yet, people still sit around reading these type of research papers, lights on, cigarette in hand. 

I predict that no matter how many research projects prove there are ways to decrease fertilizer use and slow phosphate consumption, it will never happen.

Maybe not tomorrow, but in the next couple of decades, people will look back on this type research and wonder why we chose to ignore such simple answers to complex problems. 

So, maybe I should do my part and not have mushrooms for dinner tonight… we are going to need all the fungi we can get!

Reference 

Xiao, C.  Chi, R.  He, H.  Qiu, G. Wang, W. and  Zhang, Z. 2009. Isolation of Phosphate-Solubilizing Fungi from Phosphate Mines and Their Effect on Wheat Seedling Growth. Appl Biochem Biotechnol, 159, 330–342.