Morphological Characteristics of Agronomic Crops Quiz

Morphological Characteristics of Agronomic Crops

• Grasses feature a single blade, sheath, and ligule, with optional auricles present. Leaves are typically arranged alternately.
• The sheath encases the internode, and major grain crops include wheat, corn, and barley.
• Leaves possess parallel veins, originating from the base to the apex, prominently featuring a midrib.

Legumes Characteristics

• Leguminous plants exhibit trifoliate compound leaves where leaflets connect to the main stem via petioles and petiolules.
• Stipules are leaf-like structures located at the petiole's base where it joins the stem.
• Sessile leaves are those directly attached to the shoot; these typically have netted veins with one or more prominent veins.
• Leaf venation patterns include:
  • Pinnately veined: a single midrib with diverging branches.
  • Palmately veined: several principal veins branching from the base.

Flower Structures in Grasses and Legumes

• Grass flowers commonly form a terminal inflorescence known as a spike or loose panicle, consisting of a central stem (rachids) with branches (rachillas) supporting spikelets.
• Each spikelet comprises two glumes and may contain one or more florets.
• Legume flowers can occur as solitary blooms or as inflorescences and consist of sepals, petals, stamens, and pistils.

Plant Families

• Poaceae family: includes monocotyledons like wheat, barley, corn, and other grasses.
• Fabaceae family: consists of dicotyledons, including chickpea, soybean, and alfalfa.
• The grass family provides grain-bearing crops and forage grasses pertinent to livestock production.

Root Systems in Grasses and Legumes

• Grasses possess a fibrous root system, which effectively anchors the soil and helps mitigate soil erosion.
• Legumes utilize a tap root system, enhancing drought resilience and soil fertility through deeper penetration.
• Certain legumes can fix atmospheric nitrogen through symbiotic relationships with Rhizobium bacteria in root nodules.

Stem Characteristics

• Grass stems are primarily herbaceous and lack secondary growth; they often appear green due to chlorophyll, with limited photosynthetic efficiency compared to leaves.
• The culm is characterized by distinct internodes that are hollow and separated by nodes, which are solid regions where leaves attach and buds are found.
• Erect, cylindrical stems develop lateral buds that form branches called tillers.

Leaf Functionality

• Leaves are vital for photosynthesis, serving as the principal food production organ.
• They also facilitate transpiration, the process of water movement through the plant.