Agronomy - Study Mode
[#481] Which one of the following pairs of weeds and crops is not correctly matched
Correct Answer
(C) Typha : Sugarcane
Explanation
Solution: Striga commonly known as witchweed is a genus of parasitic plants that occur naturally in parts of Africa, Asia, and Australia. Sorghum is the most common crop affected by striga. Cuscuta compestris is a parasitic plant that belongs to the family Convolvulaceae. It is a pest of Lucerne. Typha is an aquatic or semi aquatic rhizomatous, herbaceous perennial herb plant. It is not a weed, it is a useful plant and source of fibre for rayon and crude. Thus its combination with sugarcane is wrong. Orobanche is a flowering parasite on tobacco roots and occurs in all the tobacco tracts in India.
[#482] How much potash required for arhar?
Correct Answer
(A) 40 - 60 kg/ha
Explanation
Solution: Potash i.e. potassium is one of the essential nutrient elements required by the plant for plant growth. It helps plants use water and resist drought and enhances yield. Arhar contains a good amount of potassium, iron, iodine and essential amino acids which make it a good and healthy food supplement. During the cultivation of arhar, about 40 - 60 kg/ha of potash is required for good quality yield.
[#483] The botanical name of macaroni wheat is
Correct Answer
(D) Triticum durum
Explanation
Solution: Durum wheat is also known as Pasta wheat or macaroni wheat. It is a tetraploid species of wheat and is the second most cultivated species of wheat after common wheat. Durum in Latin means hard and the species is the hardest of all wheat. It contains about 12% total protein in defatted flour compared to 11% in common wheat also durum wheat contains 27% extractable wet gluten compared to 24% in common wheat.
[#484] The organic residues with wider C : N ratios as compared to narrow C : N ratios are decomposed at
Correct Answer
(B) Slow rate
Explanation
Solution: C : N ratio is the mass of carbon to the mass of nitrogen in organic residues. The optimum ratio of C : N for the desired decomposition of organic crop residue is 24 : 1. It should be in proper carbon and nitrogen ratio that a microorganism can survive healthily in it. The organic residues with wider C : N ratios as compared to narrow C : N ratios are decomposed at a slow rate.
[#485] If only three irrigations are available indicate critical stages or wheat when these will be applied
Correct Answer
(A) Crown root initiation, flowering, doughing stage
Explanation
Solution: The correct answer is A: Crown root initiation, flowering, doughing stage. Let's break down why: Understanding Critical Stages: Wheat needs water most during certain key growth phases. Missing irrigation at these times can drastically reduce yield. Option A: Crown Root Initiation (CRI), Flowering, Doughing Stage: * Crown Root Initiation (CRI): This is the most crucial stage. It's when the plant establishes its permanent root system. Lack of water here severely limits growth. * Flowering: This is when the plant is forming grains. Water stress at flowering reduces the number of grains that develop. * Doughing Stage: This is the grain-filling stage. Water here ensures plump, heavy grains, directly impacting yield. Why the other options are less ideal: * Option B: Tillering, jointing milking: While these stages are important, CRI is more important than tillering.
* Option C: CRI, tillering, doughing stage: Flowering stage is a more crucial stage.
* Option D: CRI, late jointing and dough stage: Flowering stage is a more crucial stage. In summary: Prioritizing irrigation at Crown Root Initiation, Flowering, and the Doughing Stage gives wheat the best chance for strong growth and a high yield when only three irrigations are possible.