Our nature also has lot of nutrients that can potentially be used by plants. But these nutrients are like the wealth of the miser. They are there but not usable. For example, many types of rocks are rich sources of phosphorus. The phosphorus content can be as high as 30%!
As we have already discussed, Phosphorus is one of the important nutrients needed by the plants. Why can’t these plants utilize these phosphate reserves naturally available in the soil?
The irony is that even if we provide Phosphate rich chemical fertilizers to the plants, sooner or later these phosphorus compounds turn into the ‘wealth of the miser’ locked up and useless.
Why does this happen?
The problem is that the plants can only absorb these nutrients through their roots along with water. That means, to be useful, these nutrients should be soluble in water. Unfortunately, most naturally occurring phosphorus resources are not soluble in water. And even when we provide artificial chemical fertilizers rich in phosphorus, most of it turn into water insoluble compounds. They are once again the riches of the miser. They are there, but not useful!
What is the way out?
Once again, we need to take the help of the dwarfs like we did in the Nitrogen fixing case that we discussed in the previous episode. In nitrogen fixing case, those bacteria could produce nitrogen compounds by absorbing atmospheric nitrogen. But here, we don’t need to produce anything but only make them available.
There are several microorganisms that can convert the phosphorus compounds, either naturally occurring or provided artificially through chemical fertilizers, into water soluble forms.
One common bacterium that can do such a miracle is Pseudomonas.
These bacteria are called phosphorus fixing bacteria. They produce organic acids that react with water insoluble phosphorus compounds and convert them into water soluble compounds. Once such a conversion takes place, the plants can easily absorb them and utilize them to satisfy one of their basic needs.
By merely treating the seeds with these bacteria before planting the seeds, we can reduce the Phosphorus need of the grown plant by almost 50%. That means you need to provide only half the normal amount of phosphorus-based fertilizer to the plants.
These bacteria don’t produce Phosphorus but help in better utilization of Phosphorus that is either available naturally or provided through artificial means. Indirectly, it is as good as producing them.
In the same manner, there are bacteria that can ‘fix’ potassium occurring in the soil and make them easily available to the plants. As we discussed earlier, potassium is another important nutrient that the plants need.
If we produce nitrogen using the nitrogen fixing bacteria, convert phosphorus and potassium in the soil to water soluble compounds, once again using appropriate bacteria, then we have solved all the basic needs of the plants.
This is not a one-time solution. As long as the bacteria are maintained, they keep providing these nutrients endlessly, with minimal intervention from us. That is self-propelled endless source of nutrients. You probably will never bother to look at chemical or even organic fertilizers any more. Our little friends would do the job for us.
Let us continue our discussions in the next episode. Thank you.
A series of weekly (every Monday 12 PM PST) talks on new ways of Gardening by Dr. King. © Dr. King 2019
No comments:
Post a Comment