Browsing by Author "Wijesekera, G.A.S."

Now showing 1 - 9 of 9

Acclimatization of micropropagated plants of Hevea
(Rubber Research Institute. Agalawatta, 1993) Seneviratne, P.; Wijesekera, G.A.S.; De Soysa, G.M.
In vitro produced Hevea shoots were successfully acclimatized to outdoor conditions by controlling the ambient conditions, mainly the humidity. Shooots, longer than 5 cm and with some leaves attached performed better. Shoots without roots produced shoots soon after their transfer to soil and the root development and the acclimation succes was better than in the rooted shoots. Use of a concentrated auxin solution, to soak the bases of the shoots or to incoroperate into soil improved root induction. The growth of the aerial part and the root system of the micropropagated plants were comparable to those of embryo cultured plants, up to one year of growth, but the field performance is yet to be monitored.
A century of rubber research - developments in rubber planting materials
(Rubber Research Institute of Sri Lanka. Agalawatta, 2009) Seneviratne, P.; Wijesekera, G.A.S.
Development of tissue culture techniques for rubber (Hevea brasiliensis Muell Arg.)
(Rubber Research Institute of Sri Lanka. Agalawatta, 2009) Nayanakantha, N.M.C.; Seneviratne, P.; Wijesekera, G.A.S.
Effect of GA3 on the growth of axillary buds of Hevea brasiliensis in vitro
(Rubber Research Institute. Agalawatta, 1997) Seneviratna, P.; Wijesekera, G.A.S.
Slow growth of axillary buds is one of the key reasons for the slow progress in micropropagation of clonal Hevea.Axillary buds induced in the presence of cytokinins were elongated satisfactorily in the presence of GA3 at 2-4 mg/1.This effect was not observed when the medium contained thidiazuran.The effect of filter sterilized and autoclaved GA3 on the elongation of in vivo grown seedlings showed no difference.However,in this study GA3 was incorporated in to media prior to autoclaving.
The effects of the basic medium and the carbohydrate content on shoot cultures of Hevea brasiliensis
(Rubber Research Institute. Agalawatte, 1996) Seneviratne, P.; Flegmann, A.W.; Wijesekera, G.A.S.
Woody Plants Medium (WPM) was superior to murashige and skoog medium (M S), which showed better axillary bud growth of both juvenile and mature shoot materials. The effect was more pronounced in later passages, in particular, on the survival rate of the cultures. Most of the cultures grown on M S medium did not survive more than 24-28 weeks, while on WPM medium cultures survived for more than one and a half years, until the experiment was terminated. The level of sucrose in the medium also had an effect on the growth of the primary axillary shoots, specially the length and the leaf growth. The length of primary axillary shoots incresed with the increasing levels of sucrose in the medium up to 10 per cent with clonal materials. Explants did not survive beyond 8 weeks when the medium was not supplied with sucrose.
The growth phase and its effect on bud proliferation and growth of in vitro culture of Hevea brasiliensis
(Natural Resources Energy Science Authority:Colombo, 1994) Seneviratne, P.; Wijesekera, G.A.S.
The positional effect of the explant on In vitro growth of axillary buds of Hevea brasiliensis
(Rubber Research Institute. Agalawatte, 1996) Senaviratne, P.; Flegmann, A.W.; Wijesekera, G.A.S.
Apart from the high apical dominance showed in shoot explants of hevea, the location of the node in the shoot, seems to play a vital role in in vitro axillary bud proliferation. Better performance was observed when the axillary buds harvested as nodes, were not too close and also not too far from the apex as measured by the primary axillary shoot growth. This was true for both juvenile and mature arigin materials. Furthermore, "active" nodes were superior to "dormant" nodes.
The problem of surface sterilization of shoot materials of Hevea
(Rubber Research Institute of Sri Lanka. Agalawatte, 1995) Seneviratne, P.; Flegmann, A.W.; Wijesekera, G.A.S.
Treatment with nitric oxide and seed coat removal improve germination and growth of rubber (Hevea brasiliensis)
(Rubber Research Institute:Agalawatta, 2016) Nayanakantha, N.M.C.; Madhushani, K.D.; Amarathunga, L.A.R.; Wijesekera, G.A.S.; Pathirana, P.D.; Karunatilaka, W.; De Zoysa, D.L.N.; De Alwis, M.N.; Handapangoda, R.; Seneviratne, P.