How do plants get nutrients

How do plants get nutrients?

Ans:

Plants get nutrients from air, water, and soil. Soil is the major source of nutrients. Thirteen of these nutrients are available from soil. The remaining three nutrients (carbon, oxygen, and hydrogen) are obtained from air and water.

Compare the use of manure and fertilizers in maintaining soil fertility

Q. No. 1:

Compare the use of manure and fertilizers in maintaining soil fertility.

Ans:

Manures increase soil fertility by enriching the soil with organic matter and nutrients as it is prepared by the decomposition of animal excreta and plant wastes. while fertilizers are inorganic compounds whose excessive use is harmful to the symbiotic micro-organisms living in soil.

So they are preferred only for short period of time.

What are the desirable agronomic characteristics for crop improvements

What are the desirable agronomic characteristics for crop improvements?

Ans:

The desirable agronomic characteristics for crop improvements are:

(i)  Tallness and profuse branching in any fodder crop.

(ii)  Dwarfness in cereals.

These desirable agronomic characteristics help in increasing crop productivity.

What are macro-nutrients and why are they called macro-nutrients

Q. No. 1:

What are macro-nutrients and why are they called macro-nutrients?

Ans:

Macro-nutrients are those nutrients which are required in large quantities for growth and development of plants. Since they are required in large quantities, they are known as macro-nutrient. The six macro-nutrients required by plants are nitrogen, phosphorus, potassium, calcium, magnesium, and sulphur.

How do biotic and abiotic factors affect crop production

Q. No. 1:

How do biotic and abiotic factors affect crop production?

Ans:

Biotic factors such as pests, insects and diseases reduce the crop production. A pest causes damage to our crops by feeding. Weeds also reduce crop productivity by competing with the main crop for nutrients and light.

Similarly, abiotic factors such as temperature, wind, rain etc. affect the net crop production. For example droughts and floods have a great impact on crops sometimes, destroying the entire crop.

What do we get from cereals, pulses, fruits and vegetables

Q. No. 1:

What do we get from cereals, pulses, fruits and vegetables?

Ans:

(i)  From cereals we get carbohydrates.  

(ii)  From pulses we get proteins.

(iii)From fruits and vegetables we get vitamins and minerals. We also get small amount of proteins, carbohydrates, and fats from them.