Development of storage techniques for thampakam (Hopea parviflora Bedd.) seeds

Abstract

A detailed study was conducted at College of Forestry, Kerala Agricultural University, Vellanikkara, Thrissur, Kerala during 1999-2001 to develop a suitable storage technique for the seeds of Hopea parviflora Bedd. species through synthetic seed and cryopreservation technology. Moisture content of intact seeds/ seeds without seed coat/: excised embryonic axes decreased with increase in intensity and duration of desiccation levels and only the seeds without seed coat showed significant difference in moisture content due to maturity levels. Leachate conductivity was not significantly affected due to maturity levels of intact seeds and excised embryonic axes. But seeds without seed coat showed significant difference in leachate conductivity due to maturity levels and it was higher at seven weeks after anthesis. Increasing the duration of desiccation significantly increased the leachate conductivity of intact seeds/ seeds without seed coat! embryonic axes. Germination parameters of intact seeds and seeds without seed coat were not affected significantly by increased desiccation. However, excised embryonic axes showed significant difference in germination parameters when the intensity and duration of desiccation was increased. The synthetic seeds developed from these desiccated axes also showed significant difference in their germination parameters. Synthetic seeds stored at 4°C retained maximum viability after four weeks, compared to those stored at 200 C and 27 0 C. When stored at 27 0 C, the synthetic seeds developed from six weeks mature embryos retained viability up to three weeks whereas those at seven weeks after anthesis retained viability up to two weeks only. After cryopreservation, the propagules invariably failed to regenerate but could retain green colour for two to three days.