In Pakistan, more than 76% of soil is affected by soil erosion and one billion tons of fertile land turns into eroded land. Various fertilizers experiments were conducted in different areas of Pakistan and observe the loss of nutrients in soil like potassium, phosphorus, nitrogen, copper, zinc, sulfur, iron, and manganese. Potassium is present in soil naturally but in an unavailable form.
Capital University of Science and Technology, Islamabad Pakistan
Farmers used fertilizers to increase the amount of potassium in the soil. Excessive use of chemical fertilizers pollutes soil and air, releases greenhouse gases, causes hardening of soil, and decreases the fertility of the soil. Microbes are the indicators of soil health and can be used to solubilize the unavailable potassium in the soil. It is better to use microbes to solubilize the unavailable form of potassium in the soil than chemical fertilizers. Microbes provide long-term benefits to soil and enhance the fertility of the soil. The purpose of our study is to solubilize the unavailable potassium in soil via microbes and decrease the use of chemical fertilizers.
Microbes like bacteria, fungi, yeast, and actinomycetes can solubilize the unavailable potassium in soil via the process of mineralization. The discharge of potassium from the soil is started via the production of microbial organic acids. Teotia and his co-workers performed research in New Delhi and demonstrate the process of potassium solubilization. This production is started during proliferation in the rhizosphere. The microbes of the rhizosphere produce organic acids like oxalic acid, citric acid, and malic acid. These organic acids provide protons and complex Ca2+ ions in the soil and increase the solubilization of potassium.
Relationship with SDGs
The Sustainable Development Goals (SDGs) are termed as the Global Goals which were adopted by all United Nations Members in 2015 as a universal call trying to act on ending poverty, protecting the planet, and making sure that all people will enjoy peace and prosperity by the end of this decade. Our document is linked with two SGDs; Zero Hunger, Responsible Consumption, and Production.
Globally, 1 in 9 people are undernourished, the vast majority of whom live in developing countries. Undernutrition causes wasting or severe wasting of 52 million children worldwide. It contributes to nearly half (45%) of deaths in children under five – 3.1 million children per year.
Achieving food security and improved nutrition, promoting sustainable agriculture, ending all forms of malnutrition, agricultural productivity, sustainable food production systems, and resilient agricultural practices is the conclusion of zero hunger SGD. This relates to our project in a way that we are trying to improve the unavailable potassium present in the soil via microbes. By doing this we can at least improve the nutrition of food growing over the plant to some extent.
There is also a standard developmental goal related to this project which is responsible consumption and production. Plant growth mainly depends upon the soil fertility, water content, and components present in soil and if we are somehow able to break potassium component via microbes or make it available for the plant to use it will create a huge impact and for the case of consumption, there is also need to guide people about what they are eating and what is the nutritional value of the food they are consuming in and what are the effects they are bearing while consuming nutrition-less food or nutrition full food.
Various experiments were performed related to potassium solubilizing microbes and produced satisfactory results. Mikhailouskaya and his fellow in Minsk (Belarus) inoculate (introducing bacteria into culture) potassium solubilizing microbes in roots wheat plant and get good results.
Prajapati and his co-worker’s isolated potassium-solubilizing bacterium Enterobacter hormaechei and a fungal strain Aspergillus terreus. They studied their effects and nutrients uptake on Abelmoschus esculentus (okra) in potassium deficient soil via pot experiments. Soil microbes were able to mobilize potassium in the okra plant.
Juanjuan Wang and his co-workers were inoculated bacterial combination with better growth-promoting effects into roots of wheat plants in Yangling, China (2020). Wheat is a staple food in China. The available nitrogen, phosphorus, and potassium were checked after eighty days. As result, alkali-hydrolyzed nitrogen, potassium, and phosphorous were increased as compared to the control group. Rhizobium larrymoorei released a high amount of available potassium.
Priyanka Parmar and her co-workers isolate potassium solubilizing bacteria from rhizosphere soil via insoluble mica powder-based Aleksandrov medium (mica are oil-soluble pigments and medium is designed to support the growth of micro-organisms) in India. The capability of bacterial strains to dissolve the unavailable potassium was identified by measuring the zone of clearance around the colonies because the solubilization property produced a clear zone around the bacterial colonies. Oxalic acid, tartaric acid, citric, and succinic acids were observed by High-performance liquid chromatography and these acids are vital for the solubilization of unavailable potassium. By using this method, any bacterial strains can be easily isolated from soil or rocks and check their ability to solubilize potassium before inoculating into the soil.
First of all, potassium solubilization bacterial strain will need to be isolated from soil or rocks and then they will grow on a culture medium. Inoculum of bacterial strains will be prepared in Laboratory. There are two methods for mix inoculum with seeds.
Seeds can be inoculated with bacterial stain before sowing.
Soil can be inoculated before starting the sowing process. For this method, the application should perform on moist soil. Put dry sand into the bucket and add inoculum into it according to requirement. Close the lid tightly and mix the bucket well until inoculum and sand are thoroughly mixed. Open the bucket and observe it for perfect mixing. Distribute the diluted inoculant in a band over 100m of the furrow. Seeds will place immediately after inoculation and close the furrow after sowing seeds to protect them from sunlight and heat. Try to irrigate if possible.
This method will enhance the amount of soluble potassium in soil without the use of chemical fertilizers. It will be beneficial for our agricultural industry. It will not only increase the amount of available potassium in soil but also promotes the health of the soil.