Agricultural Science

Agricultural terms and definition, letters P and Q

Biola Emmanuel - Sat, 22nd June, 2019 @ 15:19: PM

Agricultural terms and Definitions:

As a student, having the knowledge of various agricultural terms will enhance your understanding of agricultural science. In this article we will look at agricultural terms beginning with letters “P” and “Q


  • Parasite Load

This is the total number of parasites that are present in a host organism.


  • Parasite

A parasite is any organism that lives on another organism (called the host), feed on it, benefit at its expense and eventually causes harm to it.

An example of a parasite is plasmodium whose hosts are humans. Plasmodium (malaria parasite) is responsible for causing malaria in humans.

Plasmodium is a protist. You can read on the characteristics of protists here


  • Parenchyma

The parenchyma is a plant supporting tissue composed of cells with simple pits. They also help plants to metabolize and store their food materials. The two types of parenchyma cells recognized in plants are:

  1. Axial parenchyma: The cells are seen in vertical positions.
  2. Ray parenchyma: The cells lie in horizontal positions.


  • Parturition

This is the process whereby an animal gives birth to one or more offspring.


  • Pasteurization

This is the process of preserving milk by passing it through a mild temperature (usually less than 100oC) in order to kill all harmful bacteria; without changing the physical and chemical composition of the milk. Other products that can be preserved through pasteurization include yogurt, cheese, beer and wine.


  • Pastoralism

This is when a person or group of people go about their lives by raising and herding livestock such as cattle, sheep and goats.


  • Pastures

This is an area of land used for forage and grass production on which farm animals like cattle, sheep and goats graze on.


  • Peat

A peat is formed when vegetative materials are allowed to decompose partially into organic matter under wet conditions.


  • Peat soils

These are soils that are formed from dead and partially decayed organic matter in a wet land.


  • Peatland

This is a general term used on an extensive area of wetland where peat has been formed.


  • Permanent Wilting Point

A plant is said to have reached the permanent wilting point when it has lost so much water to the extent that even when it’s put in a humid environment with enough watering, it will still not be able to recover.


  • Pest

A pest is any organism that attack plants and plant products, causing damage and illness in the process. Please read on agricultural pest and the crops they attack here


  • Pesticides

These are chemicals or substances used for preventing, repelling and destroying pest on an agricultural land. You can read on pest of agricultural importance here


  • pH

This is the degree of acidity or alkalinity. A soil that has a pH of 0 – 6.9 is said to be acidic. A pH value of 7 is neutral while the pH with values 7.1 – 14 is considered to be alkaline.

The ideal pH of a soil for the optimum growth of most agricultural crops is between the values of 6 to 7.5.


  • Photosynthesis

This is the process through which green plants manufacture sugars by utilizing carbon(IV)oxide (CO2) and water (H2O) in the presence of sunlight; as oxygen is given off as a by-product.

Photosynthesis usually occurs in the green leaf of plants although it can also occur in the plant’s stem. The chlorophyll present in the chloroplast of plant’s leaf traps the needed sunlight energy for photosynthesis. Please read on autotrophic nutrition and photosynthesis here.


  • Phytoplankton

These are large communities of tiny or microscopic aquatic organisms (photosynthetic bacteria, algae, dinoflagellates, diatoms, plants and plant-like protists) living on water.

It may interest you to know that more than 60% of earth’s oxygen comes from the photosynthetic activities of phytoplanktons.


  • Pistil

This is the female part of a flower comprising of the ovary, stigma and style.

Note: the flower is the reproductive part of a plant.


  • Pith

These are group of parenchyma like cells with intercellular spaces; and are located inner to the plant’s vascular tissues (xylem and phloem), occupying the central region.


  • Pig

A pig is a young swine that weighs less than 54.4 kilogram.


  • Plant available water

This is the amount of soil water that can be absorbed by plant roots.


  • Plant gums

This is an overall term for the viscous and adhesive plant substances that are usually produced as exudates from the bark of trees and shrubs.

Plant gums are sugars in nature. Examples of gums are pine and spruce gum.


Read on (letters P and Q) part 2 here

Read on Agricultural terms and definitions, letters A - D here

Read on Agricultural terms and definitions, letters I - O here

THANKS FOR READING - Please Help Share!

Amazing facts in Agricultural Science

A group of cows 🐄 🐄 🐄  is called a team, drove or herd.

People just prefer to call them herd

NOTABLE POINTS IN Agricultural Science