Agronomy - Study Mode

[#371] Which clay mineral is rich in potash
Correct Answer

(C) Illite

Explanation

Solution: Lllite is a group of closely related non-expanding clay minerals. It is a secondary mineral precipitate and an example of phyllosilicate, or layered alumino-silicate. Its structure is a 2 : 1 sandwich of silica tetrahedron (T) - alumina octahedron (O) - silica tetrahedron (T) layer. Illite is a clay mineral is rich in potash.

[#372] Which one of the following diseases of pigeonpea is transmitted by Eryophid mite
Correct Answer

(D) Sterility mosaic

Explanation

Solution: Eriophyid mites are translucent, cigar-shaped microscopic mites that cause deformities on many plant species including pigeon pea. It helps in the transmission of pigeon pea sterility mosaic disease (SMD) caused by a mosaic virus. SMD is also known as 'Green Plaque' is an evolving disease that leads to a great loss of yield.

[#373] IR-8 variety of rice is introduced in India from
Correct Answer

(B) Philippines

Explanation

Solution: IR8 is a high-yielding semi-dwarf variety of rice developed by IRRI in early 1960, also known as miracle rice celebrate for fighting famine and played a significant role in the Green revolution. It was introduced in India from the Philippines in November 1966.

[#374] Dendrometer used for measuring
Correct Answer

(B) Trunk Diameter

Explanation

Solution: Dendrometer is the instrument that measures the dimensions of trees, such as the diameter of their trunk, its size, shape, age, overall volume, the thickness of the bark, etc. It helps in the analysis of tree stands, diameter at breast height, the height of the tree, contraction, and relaxation of vessels, and horizontal dimension of the canopy.

[#375] If the rate of application per hectare is 3.00 kg a.i., the quantity of simazine WP (80% a.i.) required to be sprayed in 0.20 hectare area would be
Correct Answer

(B) 0.75 kg

Explanation

Solution: Simazine is a selective herbicide used for the control of broadleaf weeds and annual grasses. It is recommended to be given in kg of a.i/ha or a.i %. Formula: $$eqalign{
& { ext{Amount of herbicide}} cr
& = { ext{ }}frac{{{ ext{recommened rate}} imes { ext{spray area}}}}{{{ ext{a}}{ ext{.i }}\% { ext{ of WG/WP/Dust}}}} imes { ext{100}} cr
& { ext{Amount of Simazine required}} cr
& = frac{{left( {3 imes 0.2}
ight)}}{{80}} imes 100 cr
& = 0.75{ ext{ kg}} cr} $$