Search

Poor and staggered seeds germination is the major hurdle in plantation establishment of sandalwood (Santalum album L) which is one among the esteemed timber species of the world. Nutrient priming is an innovative approach that combines the positive effects of seed priming and improved nutrient supply thereby helping in mass production of quality seedlings. In the present investigation, the effect of nutripriming using MnSO4 on germination and seedling growth of the sandal was studied. The experiment was conducted in two factorial CRD with concentration of MnSO4 (0.4M, 0.6M, 0.8 M and 1 M) and duration of treatment (3, 6, 9 and 12 days) as factors. Results indicated that seeds subjected to nutripriming at 0.8 M for 3 days recorded the highest germination (88.0%) followed by those soaked at 0.4 (86.7%), 0.6 (86.7%) and 1.0 M (86.0%) concentrations respectively. The nutri-primed seeds incubated for more than 3 days recorded a germination < 10%. Multivariate analysis indicated that the seedling growth and biomass production were also higher at 0.8 M concentration for 3 days followed by 0.4 M for 6 days. Hence, we recommend nutripriming at 0.8 M for 3 days and 0.4 M for 6 days for superior planting stock production of sandal.

Cinnamomum heyneanum Nees and C. riparium Gamble (family Lauraceae) are the two wild riparian species of Cinnamomum endemic to Western Ghats of Peninsular India. Overexploitation along with the lack of efforts replenish the resources have urged the ex situ and in situ conservation of these species. The objective of the present study was to explore the possibility of vegetative propagation through branch cuttings and juvenile epicormic shoots in planting stock production of these species. The effect of cutting type, time of collection, auxin type and auxin concentration on adventitious rhizogenesis of branch cuttings and epicormic shoots were studied. Results indicated that all these factors significantly affected the rooting efficacy of cuttings. The branch cuttings of C. heyneanum recorded a maximum rooting of 69.0 ± 2.0% and that of C. riparium was 70.7 ± 7.4%. The highest percentage of rooting was obtained in semi-hardwood cuttings treated with IBA 7000 mg l−1collected during September–December. Meanwhile, the juvenile epicormic shoots under best treatment combination could produce rooting up to 94% in C. heyneanum and 93% in C. riparian. The highest sprouting and rooting were observed in the epicormic shoots produced in the cuttings collected during January to April treated with 5000 mg l−1 IBA. The present study reveals that both the Cinnamomum species are amenable to macro-propagation and a better sprouting and rooting response can be obtained by using juvenile epicormic shoots compared to branch cuttings.

The East Indian sandalwood (Santalum album L), one among the valued timber species in the global market due to its sweet-scented heartwood, is facing a drastic decline of its natural populations over the past three decades. The major constraint in the regeneration of sandal is the slow, staggered, and poor germination of the seeds. The germination may continue even up to one year. The present investigation focused on the impact of biopriming on the germination and seedling performance in sandal. Fresh mature seeds of sandal were procured from the Nachivayal Reserve Forest, Marayur Sandal Division. The seeds were subjected to 16 biopriming treatments using Pseudomonas fluorescens at 4 concentrations (25, 50, 75 and 100%) and 4 durations (2, 4, 6, and 8 days). The results revealed that the biopriming at 100% for 8 days recorded the highest germination percentage (88%) within 21 days with lowest energy period (15 days) and highest germination energy (62.98%). Biopriming at 50% concentration for 8 days was the next best treatment which improved the germination of sandal seeds and the lowest germination percentage was recorded in control seeds (46%). With regard to the seedling growth, the biopriming treatment contributed a significant increase in growth attributes of the seedlings. We recommend the biopriming with Pseudomonas fluorescens at 100% for 8 days as a potential technique to enhance seed germination and seedling growth in sandal.

Moisture stress is one of the major impediments in establishment of plantations since the seedlings are susceptible to moisture stress. Rapid recovery from the drought stress is as important as stress tolerance of tree seedlings. Present study evaluated the physiological and biochemical responses related with stress tolerance and recovery in plus trees of teak from different provenances. One-and-a-half-year-old ramets of eleven plus trees of teak from different provenance of Kerala were exposed to two consecutive drought treatments, till most of leaves exhibited symptoms of wilting with an intervening period of stress relief through rehydration for six days in green house nursery. During the second cycle of drought stress and recovery, physiological parameters like relative water content, canopy air temperature, photosynthesis, stomatal conductance, transpiration, chlorophyll content, chlorophyll stability index and cell membrane stability index were determined. The biochemical constituents like total soluble protein, nitrate reductase, free amino acid, proline, glycine betaine, soluble sugar, super oxide dismutase, peroxidase and malondialdehyde were also recorded in addition to leaf numbers before and after stress. The results showed that physiological and biochemical parameters are crucial to maintain seedling functions during drought and to rapidly recover after re-watering during early vegetative stage. During stress and after rehydration, accessions exhibited variation between full and partial recovery in which both genetic and epigenetic factors may play crucial role. Combinations of photo-protection, osmoregulants and antioxidants measures are employed by teak to combat drought stress. Our results also suggest considerable variation that both drought stress and recovery among the plus trees that were originally selected for growth and wood quality and the potential to use them for further breeding.

Dendrocalamus sikkimensis Gamble is a large-sized sympodial bamboo species with clustering culms and few culms. Although, profuse seeding occurred in this species during mast flowering, seed viability was very low under ambient storage conditions. Present investigation focuses on the changes in seed viability and seedling growth during accelerated ageing and associated changes in biochemistry of seeds. The seed incubation was at 42 ± 1 °C and 100% relative humidity for 0, 1, 3, 5 and 8 days. Initial germination of 51.49% in the fresh seeds declined to 11.7% after 8 days of accelerated ageing, which indicated that the seeds are of low vigour and will lose viability rapidly under natural conditions. Biochemical analysis indicated a decrease in sugar, starch and protein, starch content with the progression of accelerated ageing. The sudden decline of seed viability and germination during seed ageing can be due to biochemical changes. There was decline in the acid and alkaline phosphatase and peroxidase activity and increase in α and β-amylase activity with seed ageing. Therefore, the reduction in seed viability of D. Sikkimensis seeds can be due to changes in the biochemical characteristics and function of enzymes involved in seed reserve food depletion. The quantification of seed fat and fatty acid methyl esters also supported the same.

Cynometra travancorica Bedd. belonging to family Fabaceae is an endangered tree species endemic to Western Ghats with restricted distribution. There is an urgent need for conservation of this endangered species and the vegetative propagation techniques can play major role in planting stock production. Present study focuses on the standardisation of vegetative propagation protocol of C. travancorica using stem cuttings with different concentrations of three plant growth regulating substances in different season. The anatomical, physiological and biochemical changes of the sprouted cuttings belonging to different growth regulator treatments were also conducted. Softwood, semi hardwood and hardwood cuttings were collected in three seasons (January–April, May–August and September–December) and treated with indole 3 butyric acid, indole 3 acetic acid and naphthalene acetic acid in different concentrations. Rooting response was measured after 45 days in the mist chamber. The adventitious rhizogenesis of C. travancorica stem cuttings was influenced by type of cutting, season of collection, type of growth regulator and its concentration. Semi hardwood cuttings collected during season III treated with 8000 mg l−1 IBA recorded about 84% rooting. Anatomical studies on the sprouted cuttings treated with different growth regulator did not show any significant differences, whereas physiological and biochemical parameters of sprouted cuttings varied. Hence, we recommend this treatment combination for the large scale planting stock production.

The present study was carried out to analyse the effect of rate of growth on the wood quality of teak from samples collected from trees which were grown within India as well as from outside. Teak samples (basal discs) from 14 different locations viz. Nilambur, Malayattoor, Konni, Ranni, Vadavar (TN) and Betul (MP) within India and Myanmar, Thailand, Ghana, Benin, Cameroon, Sudan, Tanzania and Trinidad outside India were included in the study. To study the effect of growth rate on wood quality, the collected samples were classified as fast grown and slow grown based on their average ring width. Those samples having an average ring width ≥5 mm and those having an average ring width

Litter production, decomposition and nutrient release dynamics of Ochlandra setigera, a rare endemic bamboo species of Nilgiri biosphere were studied during 2011–2012 using the standard litter bag technique. Annual litter production was 1.981 t·ha−1 and was continuous throughout the year with monthly variations. Litterfall followed a triphasic pattern with two major peaks in November, 2011 and January, 2012 and a minor peak in July, 2011. The rate of decomposition in O. setigera was a good fit to the exponential decay model of Olson (1963). Litter quality and climatic conditions of the study site (maximum temperature, monthly rainfall and relative humidity) influenced the rate of decomposition. Nutrient release from the decomposing litter mass was in rank order N = Mg > K = Ca > P. Nutrient release from litter was continuous and it was in synchrony with growth of new culms. Study of litter dynamics is needed before introduction of a bamboo species into degraded or marginal lands or Agroforestry systems.

The present study was carried out to characterize the tension wood and normal wood in Acacia auriculiformis and Acacia mangium and to analyse their variation in fibre and vessel morphology. The fibre morphological characters included fibre length and diameter, fibre lumen diameter and fibre wall thickness, and those of vessels included vessel diameter and frequency. Wood blocks of 1 cm3 were obtained from the base billets of felled Acacia trees, and microtome sections were prepared. In order to distinguish tension wood and normal wood, sections were stained using toluidine blue-‘O’. In order to obtain fibre dimensions, the maceration was carried out with Jeffry’s fluid. The results revealed that the anatomical properties, viz., fibre morphology and vessel morphology, were found to vary between tension wood and normal wood. The fibre morphology of both the species followed the similar pattern in which magnitude of all the fibre properties was higher in tension wood than in normal wood. Vessel morphology of both the species followed the similar trend; however, frequency and diameter of the vessels were much lesser in tension wood than in normal wood. The present study distinctly proved the occurrence of tension wood in Acacia auriculiformis and Acacia mangium. In order to reduce the occurrence of tension wood or to prevent its occurrence, better silvicultural and management practices could be adopted, such as closer spacing, and early and proper pruning.

The present study focuses on variation in basic density and fibre morphology of important pulpwood species of Kerala, viz. Acacia auriculiformis, Acacia mangium, Bambusa bambos, Bambusa vulgaris, Erythrina indica, Eucalyptus grandis, Eucalyptus tereticornis and Macaranga peltata. Fibre morphological characters such as fibre length, fibre diameter, fibre lumen diameter, fibre wall thickness and fibre ratios such as fibre length-to-diameter ratio and shape factors which are important in pulp and paper making were determined in these species. Wood samples of selected trees were collected from various saw mills and pulp mills of the state. The samples collected were converted to blocks of size 3 cm × 3 cm × 3 cm and for each species, 11 blocks were prepared and ten were used to estimate the basic density and the remaining for maceration studies. Results indicated that basic density and fibre morphology and fibre ratios varied significantly among the species studied, and all the species were suitable for pulp and paper making. Bambusa bambos recorded the highest Runkel ratio and shape factor. The two species M. peltata and E. indica which are common in the state but under-utilised for pulp and paper making had fibre morphological parameters similar to that of other hardwood species and hence offer good potential for pulp and paper making.

Celastrus paniculatus is one of the red listed medicinal plant species belonging to the family Celastraceae. Traditional propagation techniques cannot cater to large-scale planting stock production of this valuable species due to poor seed set and seed germination hence, the vegetative propagation has to be resorted. Present investigation was carried out to standardize the vegetative propagation protocol of C. paniculatus through stem cuttings with growth regulators in different season. The anatomical, physiological and biochemical changes of the sprouted cuttings were also analysed. The adventitious rhizogenesis of C. paniculatus stem cuttings was influenced by type of cutting, season of collection, type of growth regulator and its concentration. Semi hardwood cuttings collected during season III treated with 8000 mg l−1 IBA recorded over 80% rooting. Hence, we recommend this treatment combination for the large scale planting production of C. paniculatus. Anatomical studies on the sprouted cuttings treated with different growth regulator did not show any significant differences, whereas physiological and biochemical parameters of sprouted cuttings varied due to growth regulator application.