Ex. No. 16             Study of Angiospermic pathogens

Phanerogamic parasites / Flowering plant parasites                                                                                                           Very few plants are parasitic on other plants (like weeds). They depend upon another vascular plant for food and water. All the flowering parasites are absorbs nutrients through haustoria. The flowering parasites are divided into two based on the part of the plant infection. Among the parasites, Orobanche is a monocot which infects dicot. Remaining all are dicot plants. (High osmotic pressure, Produced Pectinolytic & Cellulolytic enzymes)

Stem parasite

                                Complete / Total/ Holo stem parasite – Cuscuta sp.

                                Partial/ Semi /Hemi stem parasite – Loranthus

Root parasite

                                Complete / Total/ Holo root parasite – Orobanche sp.

                                Partial/ Semi /Hemi root parasite – Striga sp.

Flowering parasites	Other names	Infected crops	Parasite Characters	Family	Stimulating compound, characters
Cuscuta sp. – Total stem parasite Cuscuta campestris	Dodder, Gold thread, Love vein, strangle weed, Amarbel	Ornamental plants, Chilli, potato, Alfalfa, fruit trees	Thread like leafless greenish white stems and flowers are white in colour	Convolvulaceae	Zoochory, Hydrochory
Loranthus – Partial stem parasite Dendrophthoe	Giant mistletoe / Banda	Fruit trees	The hold fast may become as large as a tennis ball, the leaves are thickening in nature.	Loranthaceae	Transmitted through Birds excreta (desiccated seeds)
Orobanche  - Total root parasite, Trap crop – Flax/ Linseed	Broom rape, Tokra	Tobacco, Sunflower	Annual fleshy flowering plant, pale in colour, scaly leaves without chlorophyll. The seeds size are very minute.	Orobanchaceae	Benzopyran derivatives; Snap[ dragon like flowers & Shallow cup like appressoria
Striga sp.- Partial root parasite , Trap crop – Cotton, Peanut	Witch weed	Dry land sorghum, Maize, Sugar cane	Opposite leaves and irregular flowers with a pronounced bend in the corolla tube. They are lack of root hairs and root cap.	Scorphulariaceae	Strigol; Bulb shaped Haustorium

Among the flowering parasites, Rafflesia arnoldii on Vitis roots is said to produce largest flower in the world.

Sandalwood is a semi root parasite & Cassytha is a stem parasite affects Citrus, Orange and Apple trees