Agronomy - Study Mode

[#701] In stress condition, Leaf water potential
Correct Answer

(B) Decreases

Explanation

Solution: Leaf water potential (LWP) is a useful index of soil water stress when experienced by plants. When plants undergo water stress, under low availability of water, plants develop mechanisms to cope with water stress by decreasing LWP. Air temperature, humidity, wind and soil water availability are the factors that affect LWP.

[#702] Which one of the following is composite variety of maize?
Correct Answer

(B) Kissan

Explanation

Solution: Composite variety is a variety developed by mixing the seeds of various phenotypically outstanding lines possessing similarities for various characteristics. The first composite variety in India was released in 1967. The six maize composites were Ambar, Jawahar, Kissan, Vikram, Sona and Vijay.

[#703] Deficiency symptoms of which nutrient appear on apical buds?
Correct Answer

(C) Boron

Explanation

Solution: Deficiency symptoms of boron can be observed on apical buds. Boron is an essential microelement for higher plants, its deficiency affects depression of growing points like root tip, bud, flower and young leaf and deformity of organs like root, shoot, leaf and fruit.

[#704] Sodium ion causes dispersion of clay because
Correct Answer

(A) It has lower charge density

Explanation

Solution: The clay particles are bound together because of force between them, but the presence of a large number of huge sodium ions which has lower charge density disrupts the force between the particles and hence it causes dispersion of clay particles especially when the soil is wet.

[#705] Indicate the percentage of irrigated area in India.
Correct Answer

(C) 40% - 48%

Explanation

Solution: A total of 143 million hectares of geographic land is agricultural land in our country, out of which approximately 40% - 48% is rainfed, which relies on irrigation to fulfill the water requirements of the plants. And this percentage is about 50 million hectares.