215Glossary
Abortive: Only partially developed, such as incomplete seed or frost-nipped bud.
Abscission: The falling of leaf, twig-tip, and so on, from a clean-cut scar by a self-
healing wound.
Acidic soil: Soil with a pH measure below 7 and also called sour soil.
Acre: A measure of land totalling 43,560 square feet. A square acre is 208.75 feet
on each side.
Aeration: Introduction of air to compacted soil by mechanically removing plugs of
top soil. Aeration helps oxygen, water, fertiliser and organic matter to reach
roots.
Air layering: A specialised method of plant propagation accomplished by cutting
into the bark of the plant to induce new roots formation. It is a process of
producing a new plant by forming soil around a stem.
Alkaline soil: A soil with a pH higher than 7.0 is an alkaline soil. pH is a measure of
the amount of lime (calcium) contained in soil.
Amendments: Organic or mineral materials, such as peatmoss, compost, perlite,
and so on, are used to improve the soil health.
Androecium: Stamens of a flower, as a unit.
Andromonoecious: Refers to a plant species in which male and bisexual flowers are
produced on the same plant.
Anther: The pollen-bearing part of a stamen, borne at the top of a filament or sessile.
Anthracnose: A fungal disease that causes spots on foliage or fruit and often death
of plant.
Aphid: A small green or white insect that sucks juices from plant parts.
Articulated laticifers: A laticifer is a type of elongated secretary cell composed of a
series of cells joined together found in the leaves and/or stems of plants that
produce latex and rubber as secondary metabolites.
Asexual reproduction: Duplicating a plant from any cell, tissue or organ of that
plant.
Auxin: A chemical that stimulates plant growth.
Backcross: A hybrid of two plants crossed once again back to one parent.
Berry: Berry is a fleshy fruit produced from a single flower and contains one ovary
or it is a pulpy fruit developing from a single pistil, containing one or more
seeds but no true stone.
Biennial: A plant sown one year to flower or fruit the next, then dying or being
discarded.
Biological control: Reducing pests by utilising other organisms.
Boron: A trace mineral needed by the body in only very small amounts. It assists in
the proper absorption of calcium, magnesium and vitamin D.
Carica papaya: Papaya is a giant herbaceous plant resembling a tree but not woody
in the Caricaceae family that originated in Central America and is now
grown in tropical areas worldwide for its large, sweet and melon-like fruits.