perior individual plants for a variety of purposes, including breeding programs and provision of superior
or uniform outplanting stock [46]. Observations made in the field have revealed that A. amnicolaplants
have a natural ability to produce rooted cuttings. During the monsoon season, A. amnicolawas found to
produce nodal roots from the lateral branches wherever they touched the ground. This ability is of great
importance in binding the loose topsoil. It also helps the plant to recover speedily from grazing pressure
and enables the plant to spread rapidly and multiply. Vegetative propagation is much easier in A. amni-
colabecause its nodal root formation helps in the production of a large number of rooted cuttings for field
planting.
The effects of different growth regulators used on stem cuttings for root regulation and axillary shoot
growth in different seasons of the year (Figures 2–5) are described in Secs. A–D.
A. Indole Acetic Acid (IAA)
Observations regarding the effect of indole acetic acid on root and shoot growth are presented in Figure
- Indole acetic acid did not produce much beneficial effect on root and shoot growth; it promoted roots
only when administered in lower concentrations. In higher concentrations (40 and 50 ppm) [47] during
winter and at all concentrations in rainy seasons, root and shoot growth were affected severely: there was
no root formation. IAA favored root growth only in lower concentrations (10 and 20 ppm) during the win-
ter and summer seasons, respectively. Slight yellowing and drying effects on leaves were seen at higher
concentrations.
B. Naphthalene Acetic Acid (NAA)
Figure 3 shows that compared with other auxins, NAA caused the maximum initiation of roots in cuttings.
Root growth was affected more favorably only at lower concentrations (10 ppm) during winter; at higher
concentrations the roots produced were thinner and had a minimum number of secondary roots. A distinct
effect of NAA on root growth was seen on comparing results from winter and summer. In the rainy sea-
son, the length of the root was less than during the rest of the year. Drastic inhibition of root and axillary
132 SEN AND RAJPUTFigure 2 Effect of IAA on rooting of Atriplex amnicoladuring different seasons.