Question

The plant, Ziziphus rotundifolia is an indicator of
A. Sandy loam soil
B. High lime soil
C. Soil formation
D. Soil erosion

Answer 1

Hint: Ziziphus rotundifolia is a tropical fruit tree species belonging to the family Rhamnaceae. Ziziphus rotundifolia is a spiny, evergreen shrub or small tree up to 15 m high, with a trunk 40 cm or more in diameter; spreading crown; stipular spines, and many drooping branches. The fruit is of variable shape and size. It can be oval, obovate, oblong, or round, and can be 2.5-6.25 cm long, depending on the variety. The flesh is white and crisp.

Complete answer:
Ziziphus mauritiana is a hardy tree that copes with extreme temperatures and thrives under rather dry conditions with an annual rainfall of 15–225 cm. It also grows well on laterite, medium black soils with good drainage, or sandy, gravelly, alluvial soil of dry river-beds where it is vigorously spontaneous.

In Australia, this species grows on a wide variety of soil types, including cracking clays and deep alluvials, in the tropics and subtropics where the average annual rainfall is in the range 470-1200mm. In the drier parts of this range, it grows best in riparian zones. Ziziphus mauritiana is a medium-sized tree that grows vigorously and has a rapidly developing taproot, a necessary adaptation to drought conditions.

Z. mauritiana may be erect or wide-spreading, with gracefully drooping thorny branches, zigzag branchlets, thornless, or set with short, sharp straight, or hooked spines. The leaves are alternate, ovate, or oblong-elliptic with rounded apex, with depressed longitudinal veins at the base. The flowers are tiny, yellow, 5-petalled, and are usually two or three in the leaf axils. Flowers are white or greenish-white and the fruits are orange to brown, 2–3 cm long, with edible white pulp surrounding a two-locular pyrene.

Hence, the correct option is (A), i.e., Sandy loam soil

Note: Ziziphus rotundifolia can be cultivated on saline soils under semi-arid rain-fed conditions. It is the best rootstock and prevents erosion of soil. It improves soil health, i.e., organic carbon content and reduction in pH value. It indicates sandy loam soil.