environmental stress of saline areas, plants produce a variety of ecological adaptations. Propagation
through vegetative means has been used as a method of multiplication for a number of plant species un-
der arid saline conditions.
Among factors affecting rooting of cuttings, the position of the shoot plays an important role [31]. It
is reported that without auxin treatment and without leaves, no roots were obtained in cutting of red Hi-
biscusandAllamenda cathartica[32].
Vegetative reproduction substitutes for or at least contributes to the reproductive potential of many
plants. This statement is more applicable to various halophytic species that are restricted to narrow eco-
logical limits, either in the production of disseminules or by their germination [33]. Self-layering species
ofAtriplexare at an advantage in establishing themselves in salt-affected soil, which they accomplish
faster than other species: the growth of developing roots results in rapid penetration through the upper
salty soil layers. Furthermore, roots developing at different nodes are not dependent on a direct supply of
water from the soil [34,35]. Being well supplied with water by the parent plant, roots can penetrate lay-
ers of extreme salinity.
C. Vegetative Propagation in Saline Plants
The distribution of salinity varies spatially, temporally, qualitatively, and quantitatively. In addition, the
responses of plants to salt stress vary during the life cycle of the individual [36,37]. Phenotype plasticity
involving both morphological and physiological changes in response to episodic events is an important
characteristic associated with the survival of long-lived plants under highly stressful environmental con-
ditions. Transient reductions in yield in response to salinity may be the result of the adaptive reconstruc-
tion of growth habits of a plant. The heterogeneity of saline habitats leads to considerable genetic differ-
entiation among populations as a result of natural selection: an all-purpose genotype capable of growing
in a wide range of saline habitats probably does not exist [38].
The growth and productivity of Atriplexunder conditions of low and erratic rainfall are exceptional,
and the adaptation of this species to high salinity makes its introduction very suitable [39]. Agronomic
testing, feeding trials, and development of the best agronomic practices are necessary in the evaluation of
suitable species for introduction and mass propagation [40].
Normal vegetation, except for some halophytes, cannot survive on saline and sodic soils. Thus, ar-
eas having soils of these types are of limited agricultural use unless the salinity is quite mild. Increased
salinity has rendered many lands unfit for cultivation. Plant species that are capable of accumulating large
quantities of sodium in their tissues are the least sensitive to the presence of salt in the soil. The tolerance
of a species to high amounts of absorbed or exchangeable sodium is modified by the pH of the soil and
by the accumulation of CO 2.
With increasing human and animal populations and the need for greater crop and fodder production,
nonproductive salt-affected lands may be used to grow nonconventional crops of economic value and also
such food crops as pearl millet. It is desirable to choose species well suited to saline habitats and to cal-
culate the most economical means of reclamation to make the salt-affected soils productive. The essen-
tial ingredients of technology for meeting these problems consist of the use of tolerant species, special
planting techniques, and aftercare.
Cultivation of salt-affected areas with palatable halophytes is one of the most promising and eco-
logically safe approaches in the reclamation process. It also helps cattle breeders and farmers to improve
a chronically stagnant economy. Selection of the most suitable halophytic species for introduction into
saline land needs extensive research. Malcolm [41,42] and Sen et al. [43] have produced a guide to the
selection of salt-tolerant shrubs for forage production from saline lands in southwestern Australia and In-
dia, respectively. Important selection parameters include:
- Growth and survival for a sufficient period in a representative environment
- Reproduction by seed or vegetative means
- Acceptable growth form for management use
- Production of biomass of sufficient quantity, quality, and acceptability to livestock
- Ease of establishment
- Persistence under a profitable management system
130 SEN AND RAJPUT