A

Adventitious Roots: Roots that originate from an atypical location such as the stem or leaves.

B

 

C

Cankers: Localized necrotic tissue on the stem, calyx, or penducles of the plant.

Chlorosis: The fading, yellowing or whitening of green tissue due to a decrease in the amount of chlorophyll.

Coalesce: To grow together into one spot.

Cooper Fungicides: Compounds containing copper that are used to kill fungi and bacteria.

D

Defoliation: Dropping of leaves from the plant.

Disinfect: To kill or prevent the growth of microorganisms (usually disease causing) usually by chemical means.

Distortion: Alteration or changing of the original shape or characteristic of the leaf or leaflets.

E

Emergence: The point when the seedling shoot first becomes visible through the surface of the soil.

F

Firing: Browning of the outer edges of the leaflets with a thin yellow band; also referred to as marginal necrosis.

G

 

H

Hydathodes: Leaf openings at the terminus of a vein.

I

 

J

 

K

 

L

Leaflets: One of the separate divisions of a compound leaf.  A compound leaf is made up of several leaflets.

M

 

N

Natural Openings: Openings on the plant that provide a point of entry into the plant by microorganisms.

Necrosis: Death of cells or tissue resulting in browning or blackening of a localized area on the tissue.

Nodes: Points on a stem where the leaves or buds originate.

O

On-Site Diagnostic Assay: Rapid tests that cab be conducted in the field or the greenhouse.

P

Pith: Spongy tissue that occupies the center of the stem.

Plant Disease Diagnosis: The science of examining plants to identify their diseases.

Puckering: A disease symptom in which the leaves or leaflets are cupped or pinched into bunches.

Q

 

R

 

S

Stippling: The appearance of tiny spots.

Stomata: Openings on the leaf surface required for gas exchange.

Streptomycin: An antibiotic produced by the soil bacterium Streptomyces griseus, used to kill bacterial plant pathogens.

Stunting: A disease symptom in which there is a reduction in height due to a reduction in the length of internodes or a decreased in the number of internodes.

T

Top Wilting: Wilting of shoots on the upper portion of the plant.

U

Ubiquitous: Present all the time; widespread.

V

 

W

Water-soaked: A disease symptom in which plant tissues or lesions appear wet, dark, and usually sunken and translucent.

X

 

Y

 

Z