MSc

The present study attempted root induction in the branch cuttings of three commercially
important bamboo species namely; Bambusa balcooa, Dendrocalamus giganteus and
Thyrsostachys oliveri. The primary branches of each species were collected during three
seasons viz. October to January (Season I), February to May (Season II) and June to September
(Season III). Two noded branch cuttings were prepared out of the primary branches and
subjected to soaking in growth regulator solutions of IBA and NAA at different concentrations
of 0 (control), 100, 250, 500 and 1000 mg l-1 for 24 hours and planted horizontally in two media
viz. sand alone and mixture of sand, soil and cow dung (1:1:1) filled in plastic trays.
Results indicated that sprouting attributes of bamboo species varied among different
treatments. In B. balcooa, sprouting percentage varied from 1.67 (branch cuttings of season I
treated with IBA 250 mg l-1 kept in second medium) to 48.33% (branch cuttings of season II
treated with NAA 250 mg l-1 kept in the sand). In D. giganteus, sprouting in the branch cuttings
ranged from 5.00 to 43.3%. The highest sprouting was observed during season II in cuttings
treated with NAA 500 mg l-1 kept in the second media and the least was in control of NAA kept
in sand in the same season. Meanwhile, in T. oliveri, maximum sprouting was observed in
cuttings treated with IBA 100 mg l-1 (41.67%) in third season kept in sand, while sprouting was
absent in some treatment combinations along with the control. However, sprouted cuttings
failed to initiate rooting in any of treatment combinations in three bamboo species.
Further trials were conducted with higher concentrations (0, 1000, 2000 and 3000 mg l-
1
) of growth regulators in sand medium. Maximum sprouting in B. balcooa, was observed in
cuttings treated with IBA 1000 mg l-1 (36.66%) while, the least was in those treated with NAA
1000 mg l-1 (10.00%). Branch cuttings treated with IBA 1000 mg l-1 recorded the highest
sprouting (26.66%) and those treated with IBA 3000 mg l-1 recorded the lowest value (10.00%)
in T. oliveri. Here also, the expected rooting of cuttings was not observed. Hence, another trial
with the application of NAA and IBA by quick dip method at concentrations 0(control), 1000,
1500 and 2500 mg l-1 was carried out. In B. balcooa, the highest sprouting was in the cuttings
treated with NAA 1000 mg l-1 (30%) and the lowest was in those treated with IBA 2500 mg l-
(6.00%). Whereas, in T. oliveri highest sprouting was observed in cuttings treated with IBA
1000 mg l-1 (33.33%) followed by IBA 1500 mg l-1 (23.33%). The least sprouting was observed
in cuttings treated with NAA 2500 mg l-1 (13.33 %) followed by control (15%). Here also, the
rooting was absent in different treatments. In the last experiment, B. balcooa branch cutting
were treated with IBA and NAA solutions 0, 500, 1000, 1500 and 2000 mg l-1 concentration
and planted in standard nursery beds. The lowest sprouting percentage was observed in cuttings
treated with NAA 2000 mg l-1 (20.00 %) and the highest sprouting was in cuttings treated with
IBA 500 and 1000 mg l-1 (40 %) but the sprouted cuttings did not produce any root. As the
present study did not give the expected results, further trials are needed for the standardization
of propagation through branch cuttings in the selected bamboo species.