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Ecophysiological Aspects of the Vegetative
Propagation of Saltbush (Atriplexspp.) and
Mulberry (Morusspp.)
David N. Sen* and Pramila Rajput
University of Jodhpur, Jodhpur, India
127I. INTRODUCTION
Nature has provided the phenomenon of reproduction to the living world in order to perpetuate species.
The way in which reproduction in the plant kingdom is carried out may be broadly divided into two
categories.
Vegetative propagation
Sexual reproductionSome plants at times fail to complete their life cycle by means of seeds, yet they survive and perpet-
uate themselves. This is because nature has provided an alternative to sexual reproduction, that is, vege-
tative propagation. The latter is the most common method of propagation because of various advantages,
such as maintenance of particular characteristics of the plants, relative seed in raising samplings in large
numbers for plantation, adaptability to a particular habitat, development of resistance to pests and dis-
eases, and drought tolerance to modify the growth of plant.
Propagation through seeds is mainly done to bring about a varied population for the purpose of se-
lection and hybridization. Rooting of cut pieces of stem is a prerequisite for multiplication and survival.
Trees in many cases fail to produce roots from cuttings and thus present difficulties. Among the factors
affecting rooting of cuttings, the position of the shoot plays an important role.
The multiplication of species by vegetative means is practiced in forestry and horticulture to obtain
plants of a desired genetic constitution for crossing in a breeding program for many reasons (to improve
growth and yield, stem quality, wood quantity, resistance to pests and diseases, or other desirable char-
acteristics and also to maintain the purity of types so evolved for commercial exploitation). This process
has been used for quick multiplication for a number of plant species, which is important for afforestation
purposes in arid zones, where quick growth and development of plants are very much needed.
In easily rooting species, the ability of stem cuttings to root varies considerably with the season. In
many cases, profuse rooting occurs when cuttings are taken from trees in an active season. The seasonal
rooting response of stem cuttings is related to the disappearance of starch. The hydrolytic activity is high
when rooting occurs, but is not detached when cuttings fail to root [1]. Nanda [2] showed that the effec-
tiveness of exogenously applied auxins varies with the season and that these differences may be ascribed
to changes in a plant’s nutritional and hormonal status during its annual cycle of growth.
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