Plant Breeding and Selection MCQs Quiz | Class 9

Test your knowledge with this Class IX Science (Code 086) quiz from Unit IV: Food Production. This assessment focuses on Plant Breeding and Selection, specifically covering topics like selection for quality improvement and various trait examples. Answer these 10 MCQs, submit your responses, and download the PDF solution sheet for your records.

Overview: Plant Breeding and Selection

Plant breeding is the science of changing the traits of plants in order to produce desired characteristics. It has been used to improve the quality of nutrition in products for humans and animals. In Class 9 Science, Unit IV (Food Production), this topic explains how we select crops for higher yield, better quality, and resistance to environmental stresses.

Key Objectives of Crop Variety Improvement

  • Higher Yield: Increasing the productivity of the crop per acre.
  • Improved Quality: Considerations vary by crop (e.g., baking quality in wheat, protein quality in pulses, oil quality in oilseeds).
  • Biotic and Abiotic Resistance: Developing crops resistant to insects/diseases (biotic) and drought/salinity/heat (abiotic).
  • Change in Maturity Duration: Shorter duration allows farmers to grow multiple rounds of crops in a year.
  • Wider Adaptability: Developing varieties that can grow in different environmental conditions.
  • Desirable Agronomic Characteristics: Examples include tallness and profuse branching for fodder crops, and dwarfness for cereals (to consume fewer nutrients).

Common Methods

Hybridization: Crossing between genetically dissimilar plants. It can be intervarietal (between different varieties), interspecific (between different species), or intergeneric (between different genera).

Genetically Modified Crops (GMOs): Introducing a specific gene to provide a desired characteristic, resulting in genetically modified crops.

Study Table: Desirable Traits

Crop Type Desirable Trait Reason
Cereals (Wheat, Rice) Dwarfness Less nutrient consumption, stronger stem against wind.
Fodder Crops Tallness & Branching More biomass for animal feed.
Pulses Protein Quality Nutritional value improvement.
Oilseeds Oil Content Higher extraction efficiency.

Practice Questions

  1. Why is short maturity duration preferred in crop improvement?
  2. What is the difference between intervarietal and interspecific hybridization?
  3. Name one biotic and one abiotic factor that affects crop production.
  4. Define “photoperiod” in the context of plant growth.
  5. How does “dwarfness” help in cereal crops like wheat?