Q6. (a) What are the diagnostic characters of the families – Cucurbitaceae and Poaceae ? Write the botanical names and economic importance of any five members from each family.

Diagnostic Characters of Cucurbitaceae

The family Cucurbitaceae, often referred to as the gourd family, includes approximately 965 species across 101 genera. They are primarily annual or perennial herbaceous vines, sometimes shrubs or trees, known for their rapid growth and tendril-assisted climbing habit. Key diagnostic characters include:

• Habit: Mostly annual or perennial herbaceous vines, often glandular-hairy, with prostrate, trailing, or climbing stems. Some tropical species can be woody lianas or thorny shrubs.
• Tendrils: A prominent feature, tendrils are typically present at a 90° angle to the leaf petioles at nodes, simple or branched, aiding in climbing.
• Leaves: Alternate, simple, exstipulate, and often palmately lobed or palmately compound with parallel venation. Petioles are often as long as the blade.
• Flowers: Unisexual (male and female flowers separate), often large and showy, typically pentamerous. Plants can be monoecious (male and female flowers on the same plant) or dioecious (on different plants).
• Calyx and Corolla: Sepals and petals are usually 5, gamosepalous and gamopetalous (or polypetalous in some), often yellow or white.
• Androecium: Stamens vary, often 3-5, sometimes appearing as three due to fusion, with anthers that can be free or connate and often twisted or S-shaped.
• Gynoecium: Tricarpellary, syncarpous, with an inferior ovary, typically unilocular with parietal placentation (which may intrude to make it appear trilocular).
• Fruit: Characteristically a pepo (a modified berry with a hard, thick rind), fleshy and usually indehiscent, but can be dehiscent in some species (e.g., Momordica). Fruits can be very large.
• Seeds: Numerous, flattened, non-endospermic, with a straight embryo and large, oily cotyledons.
• Vascular Bundles: Often bicollateral and arranged in two alternating rows.

Economic Importance of Five Members from Cucurbitaceae

Botanical Name	Common Name	Economic Importance
Cucumis sativus	Cucumber	Widely cultivated for its edible fruits, consumed fresh in salads, or pickled. It's a significant source of hydration and vitamins.
Citrullus lanatus	Watermelon	Highly valued for its large, sweet, juicy fruits, especially popular in summer. It's an excellent source of hydration and lycopene.
Cucurbita maxima	Pumpkin/Winter Squash	Cultivated for its large, edible fruits used as vegetables in various culinary preparations, including soups, pies, and curries. Seeds are also edible.
Momordica charantia	Bitter Gourd (Karela)	Used as a vegetable despite its bitter taste. Known for its medicinal properties, particularly in traditional medicine for blood sugar regulation.
Lagenaria siceraria	Bottle Gourd (Lauki)	The young fruits are eaten as a vegetable. Mature fruits with hard pericarps are dried and used to make utensils, musical instruments, and decorative items.

Diagnostic Characters of Poaceae

The family Poaceae (Gramineae), commonly known as the grass family, is one of the largest and most economically important plant families, comprising over 12,000 species across roughly 800 genera. They are typically herbaceous, though some (like bamboos) can be woody. Their characteristic features include:

• Habit: Mostly herbaceous, annual or perennial, with fibrous roots. Stems (culms) are typically cylindrical, hollow, and jointed with distinct nodes and internodes. Bamboos are woody perennials.
• Leaves: Alternate, distichous (arranged in two ranks), simple, exstipulate, with parallel venation. Each leaf consists of a lower sheath that clasps the stem and an upper blade.
• Ligule: A membranous or hairy appendage located at the junction of the leaf sheath and blade, preventing water and insects from entering the sheath.
• Inflorescence: Characteristically arranged in spikelets, which are the basic units. Spikelets are further grouped into compound spikes, racemes, or panicles.
• Flowers (Florets): Small, inconspicuous, generally bisexual (except in some like maize), zygomorphic, and wind-pollinated (anemophilous). Petals are absent.
• Perianth: Highly reduced to two or three minute, fleshy scales called lodicules, which swell to separate the lemma and palea during anthesis.
• Spikelet Structure: Each spikelet consists of two (rarely fewer) basal bracts called glumes, followed by one or more florets. A floret comprises the flower enclosed by two bracts: an outer lemma and an inner palea.
• Androecium: Typically 3 stamens, sometimes 6 (e.g., rice) or more, with versatile anthers.
• Gynoecium: Monocarpellary (or tricarpellary, syncarpous but functionally monocarpellary), unilocular, with a superior ovary and basal placentation. The style is usually 2 or 3, with feathery stigmas adapted for wind pollination.
• Fruit: A caryopsis (grain), in which the pericarp (fruit wall) is fused with the seed coat.
• Embryo: Small, lateral, with a single cotyledon (scutellum).

Economic Importance of Five Members from Poaceae

Botanical Name	Common Name	Economic Importance
Triticum aestivum	Wheat	One of the most important staple food crops globally, providing a major source of carbohydrates and protein. Used for flour, bread, pasta, and various other food products.
Oryza sativa	Rice	The primary staple food for over half of the world's population, especially in Asia. It is a vital source of dietary energy.
Zea mays	Maize (Corn)	A widely cultivated cereal crop used for human consumption, animal feed, and industrial products like ethanol, starch, and oil.
Saccharum officinarum	Sugarcane	The main source of sugar (sucrose) production worldwide. Also used for biofuels (ethanol) and fodder.
Bambusa vulgaris	Common Bamboo	Provides building material, scaffolding, furniture, paper, and shoots are consumed as vegetables. It has diverse uses in construction, crafts, and food.