Biofertilizers are a sustainable and eco-friendly approach to enhance soil fertility and crop productivity. These are living microorganisms that enrich the nutrient content of the soil, improve nutrient availability to plants, and foster plant growth. Unlike chemical fertilizers, biofertilizers work in harmony with the environment and promote long-term soil health. They offer several benefits that contribute to sustainable agriculture:
Biofertilizer questions and answers practice now
Key points
- Nitrogen Fixation: Nitrogen-fixing bacteria, such as Rhizobium and Azotobacter, convert atmospheric nitrogen into forms that plants can readily absorb. This reduces the need for synthetic nitrogen fertilizers, which can contribute to soil degradation and water pollution.
- Phosphorus Solubilization: Phosphate-solubilizing bacteria, like Bacillus and Pseudomonas species, release phosphorus from insoluble compounds in the soil, making it more available to plants. This helps improve root development and overall plant growth.
- Potassium Mobilization: Potassium-solubilizing microorganisms aid in releasing potassium from mineral sources, enhancing the nutrient uptake by plants. Adequate potassium levels improve plant resistance to diseases and stress.
- Enhanced Nutrient Uptake: Biofertilizers facilitate the uptake of nutrients through various mechanisms, including root colonization, production of growth-promoting substances, and improved soil structure.
- Improved Soil Structure: The activities of biofertilizers enhance soil aggregation, water-holding capacity, and aeration. This leads to better root penetration, reduced erosion, and improved overall soil structure.
- Reduced Environmental Impact: Biofertilizers reduce the negative environmental impact associated with excessive use of chemical fertilizers. They decrease the leaching of nutrients into water bodies, which can lead to eutrophication and water pollution.
- Cost-Effectiveness: While the initial investment in biofertilizers might be higher, their long-term benefits include reduced dependence on expensive chemical fertilizers and improved crop yields.
- Biodiversity Promotion: The use of biofertilizers encourages the growth of beneficial microorganisms in the soil, fostering a diverse and balanced soil ecosystem.
- Organic Farming Support: Biofertilizers align well with organic farming practices, as they contribute to the use of natural resources and minimize synthetic inputs.
Biofertilizer questions and answers
Q1. What are biofertilizers?
a) Synthetic chemicals
b) Natural fertilizers
c) Pesticides
d) Weed killers
Q2. Which of the following is a commonly used biofertilizer?
a) Ammonium nitrate
b) Urea
c) Rhizobium
d) Potassium chloride
Q3. Biofertilizers are beneficial for:
a) Depleting soil nutrients
b) Increasing soil erosion
c) Enhancing soil fertility
d) Killing beneficial microorganisms
Q4. Which group of microorganisms is commonly used as biofertilizers?
a) Insects
b) Bacteria and fungi
c) Worms
d) Birds
Q5. Azotobacter is a type of biofertilizer that contributes to the enrichment of soil with which nutrient?
a) Nitrogen
b) Phosphorus
c) Potassium
d) Calcium
Q7. Which biofertilizer helps in fixing atmospheric nitrogen in leguminous plants?
a) Azospirillum
b) Cyanobacteria
c) Rhizobium
d) Phosphobacteria
Q8. The process of converting atmospheric nitrogen into a usable form by biofertilizers is called:
a) Denitrification
b) Ammonification
c) Nitrification
d) Nitrogen fixation
Q9. Biofertilizers are eco-friendly because they:
a) Contain harmful chemicals
b) Deplete the ozone layer
c) Reduce the need for chemical fertilizers
d) Increase greenhouse gas emissions
Q10. Which biofertilizer is associated with promoting the growth of roots and enhancing nutrient uptake?
a) Azospirillum
b) Rhizobium
c) Mycorrhizae
d) Phosphobacteria
Q11. Which of the following is used as Biofertilizer?
(a) Rhizobium
(b) Blue-green algae
(c) Azolla
(d) All of these
Q12. Which of the following is not a nitrogen-fixing organism?
(a) Nostoc
(b) Anabaena
(c) Azotobacter
(d) Mycorrhiza
Q13. Which of the following is a source of bio-fertilizer?
(a) Yeast
(b) Chlorella
(c) Azolla
(d) Mold
Q14. Nitrogen fi xing bacteria make combination with cells of the roots of
(a) Pulses
(b) Rice
(c) Wheat
(d) Sugarcane
Q15. Which of the following is associated with biological nitrogen fixation?
(a) Red algae
(b) Brown Algae
(c) Green algae
(d) Blue-green algae
Q16. Blue-green algae are chiefl y used as biofertilizer in the crop of
(a) Wheat
(b) Gram
(c) Paddy
(d) Mustard
Q17. Azolla is often used as biofertilizer because it is associated with
(a) Blue-green algae
(b) Red algae
(c) Fungus
(d) Moss
Q18. Which of the following microorganisms are used as biofertilizers?
(a) Virus
(b) Fungi
(c) Protozoa
(d) Cyanobacteria
Q19. Which of the following is phosphatic biofertilizer?
(a) Rhizobium
(b) Blue-green algae
(c) Azolla
(d) Vascular Arbuscular Mycorrhiza
Q20. Leg-haemoglobin is found in
(a) Human blood
(b) Rabbit blood
(c) Legume root nodules
(d) Chicken blood
What are biofertilizers, and how do they work?
Biofertilizers are natural products containing living microorganisms like bacteria, fungi, or algae that improve soil fertility and plant nutrition. They work by establishing symbiotic relationships with plants, fixing atmospheric nitrogen, solubilizing phosphorus and potassium, and producing growth-promoting substances that enhance nutrient uptake and plant growth.
What is the difference between chemical fertilizers and biofertilizers?
Chemical fertilizers are synthetic compounds containing specific nutrient concentrations, whereas biofertilizers consist of living microorganisms that enhance nutrient availability in the soil. Chemical fertilizers offer rapid nutrient supply but can harm soil health and the environment. Biofertilizers promote sustainable agriculture by improving soil structure and fostering long-term nutrient release.
Are biofertilizers compatible with all crops?
Biofertilizers have varying effects on different crops. Some crops, like legumes, respond well to nitrogen-fixing biofertilizers like Rhizobium. However, the effectiveness of biofertilizers can depend on factors such as the crop type, soil conditions, and climate. Proper strain selection and application techniques are essential to ensure compatibility.
How are biofertilizers applied?
Biofertilizers can be applied through seed treatment, soil application, or foliar spraying. Seed treatment involves coating seeds with biofertilizer before planting. Soil application involves mixing the biofertilizer with soil around the plant’s root zone. Foliar spraying involves applying a diluted biofertilizer solution directly onto the leaves. The application method depends on the type of biofertilizer and the target crop.
Are there any challenges in using biofertilizers?
While biofertilizers offer numerous benefits, there are challenges to consider. Quality control and maintaining the viability of live microorganisms during storage and transportation can be difficult. Ensuring proper storage conditions, maintaining the right pH and temperature, and avoiding the use of chemical pesticides that may harm beneficial microorganisms are crucial for successful biofertilizer application. Additionally, the efficacy of biofertilizers can vary based on soil type and local conditions, requiring tailored approaches.