Soybean Production and Agronomy Flashcards

A set of 20 vocabulary flashcards covering soybean morphology, growth stages, maturity groups, and pest management based on the lecture transcript.

Trifoliate leaves

Leaves characterized by three leaflets attached to a single point, common in soybean plants.

Petiole

The stalk of the leaf that attaches the leaf to the plant's main stem.

Axillary buds

Buds located at the point of leaf attachment from which pods or branches can grow.

Single stem

An upright growth habit in soybeans, genetically determined, which requires more seed per acre than bushy varieties.

Traditional row spacing corn and cotton

A spacing of $36$ to $40$ in between rows, originally designed to accommodate a mule for tillage and cultivation.

Maturity groups

Genetically determined classifications (ranging from 000 to 10) that reflect when soybeans initiate flowering based on daylight length.

Seeding rate

The number of seeds planted on a per acre basis, which for soybeans can reach up to $140,000 ext{ seed/acre}$.

Optimum pH

The targeted soil acidity level for liming agronomic crops, typically between $6.0$ and $6.5$.

Three-cornered alfalfa hopper

A pest that feeds on young seedlings, creating a knot that restricts transpiration flow and may cause the plant to break.

Stink bugs

A complex of seed feeders, including brown, green, southern, and brown marmorated varieties, that are perpetual pests in soybeans.

Bradyrhizobium

The genus of bacteria (formerly Rhizobium japonicum) that forms a symbiotic relationship with soybeans for nitrogen fixation.

Nitrogen fixation

The process of capturing atmospheric nitrogen through a symbiotic relationship with bacteria, typically beginning at growth stages $V3$ or $V4$.

Equinox

The period (marking the beginning of spring or fall) when there are equal numbers of daylight and dark hours.

Summer solstice

Occurring around June 21 or 22, this is the longest day of the year and the beginning of summer.

Photoperiod sensitive

The characteristic of soybeans where the initiation of flowering is triggered by specific lengths of daylight.

Imbibition

The process of water uptake by a dormant seed that begins the germination process.

Radical

The first part of the germinating seed to emerge, functioning as the initial root.

Hypocotyl

The part of the seedling that pulls the plant through the soil surface during emergence.

Indeterminate

A growth habit where a plant continues to flower and reproduce through seed while still growing, as seen in peanuts and some soybeans.

Lodging

A condition where upright crops like soybeans fall over, hindering efficient harvest and pre-harvest preparation.