Economic and Applied Botany Questions and Answers

Answer: D

Ginger is propagated by its rhizome.

The edible part of ginger is a rhizome, a horizontal underground stem with nodes, internodes and buds. Pieces of rhizome bearing buds (seed rhizomes) are planted to raise new plants, as is also done for turmeric.

A tuber is the swollen stem tip of potato, a corm the short upright stem of colocasia or gladiolus, and a bulb the fleshy leaf-based structure of onion and garlic.

Answer: C

The hybrid of Neelum and Alphonso is Ratna.

Ratna was developed at the Fruit Research Station, Vengurla, in Maharashtra by crossing Neelum with Alphonso. It combines regular bearing from Neelum with Alphonso's quality and is free from spongy tissue.

Amrapali is a different hybrid, of Dashehari and Neelum, developed at IARI, New Delhi. Dasheri and Badami are traditional varieties, not hybrids.

Answer: C

Quinine is produced by Cinchona.

Quinine is an alkaloid extracted from the bark of Cinchona trees (family Rubiaceae), native to the Andes; it was the main treatment for malaria for three centuries.

The other plants give different drugs: Ephedra gives ephedrine (a bronchodilator), Rauwolfia gives reserpine (used for high blood pressure), and Podophyllum gives podophyllotoxin, the source of anticancer drugs such as etoposide.

Answer: A

The three alkaloids are obtained from the roots of Rauwolfia serpentina.

Indian snakeroot (sarpagandha) is the source of reserpine, the classic antihypertensive and tranquilliser, together with serpentine and ajmalicine and related indole alkaloids. The plant has a long use in Ayurveda for hypertension and insanity.

Bacopa monnieri (brahmi) yields bacosides used as memory tonics. Papaver somniferum yields opium alkaloids such as morphine and codeine. Catharanthus roseus is known for vinblastine and vincristine; its roots also contain ajmalicine and serpentine, but not reserpine, so only Rauwolfia supplies all three.

Answer: A

The best method is fumigation.

Stored grain pests such as weevils, beetles and moths live and breed inside the grain mass and even inside individual kernels. A fumigant is a gas, such as phosphine released from aluminium phosphide tablets, that penetrates the whole stack in a sealed store and kills every stage of the insects, including eggs and larvae hidden in the grain, without leaving significant residues once aired.

Systemic insecticides act through a living plant's sap and are useless in harvested grain. Heating enough to kill the insects can damage germination and quality. Biological agents are slow and cannot clear an infestation already inside the grain.

Answer: B

Micropropagation means the production of a large number of progeny plants.

It is the rapid clonal multiplication of a plant in vitro: small explants such as shoot tips or nodes are grown on a sterile nutrient medium with hormones, the shoots multiply, and each is rooted to give a plantlet. Thousands of genetically identical plants can be raised from one parent in a short time.

The 'micro' refers to the small explants and culture vessels, not to tiny plants or plants at 'microlevel'. Raising plants from microspores is anther or pollen culture, which gives haploids.

Answer: B

Saffron comes from Crocus sativus.

Saffron is the dried stigmas of the flowers of Crocus sativus, a cormous plant of the iris family grown in Kashmir, Iran and Spain. Each flower has only three stigmas, picked by hand, which is why it is the most expensive spice; its colour comes from crocin and its aroma from safranal.

Mesua ferrea is the Ceylon ironwood, Nelumbo nucifera is the lotus, and Mammea suriga is the surangi tree, whose flower buds give a dye; none produces saffron.

Answer: D

The centre of origin of coffee is Ethiopia.

Arabica coffee (Coffea arabica) grows wild in the highland forests of south-western Ethiopia, and Vavilov placed it in his Abyssinian centre of origin. From there it reached Yemen, where it was first cultivated and traded, and later spread to Asia and the Americas.

Brazil is today the largest producer, but coffee was introduced there in the eighteenth century. Peru is a producer too, and the Moluccas are the original home of cloves and nutmeg, not coffee.

Answer: B

Roccella is a source of a dye.

Species of the lichen Roccella yield orchil (orseille), a purple dye used historically for wool and silk. They are also the classic source of litmus, the pH indicator dye that turns red in acid and blue in alkali.

The other options belong to other lichens. Edible lichens such as Parmelia are used as a condiment (the spice 'kalpasi' in Indian cooking). Usnic acid from Usnea and Cladonia is the best-known lichen antibiotic, and Cetraria (Iceland moss) is used medicinally.

Answer: A

These crops originated in the Hindustan centre.

Vavilov's Indian (Hindustan, or Indo-Burma) centre of origin is credited with rice, mango, the noble canes (Saccharum officinarum, sugarcane), brinjal (eggplant), cucumber, black pepper and many pulses.

The Abyssinian centre is associated with crops such as coffee, teff, sorghum and durum wheat. The Asia Minor (Near Eastern) centre gave wheats, barley, lentil and fig. The China centre gave soybean, tea, many millets and peach. None of them is the home of mango and noble canes.