Impact of thinning and pruning on tree growth, stress wave velocity, and pilodyn penetration response of clonal teak (Tectona grandis) plantation

Gama Widya Seta,Widiyatno,Fanny Hidayati,Mohammad Naiem 한국산림과학회 2021 Forest Science And Technology Vol.17 No.2

The objective of this research was to examine the impact of different thinning and pruning intensities on the growth characteristics and wood properties of clonal teak. A 14-year-old clonal teak plantation was used in the study. The first thinning and pruning were established 5 years after planting. Three different levels of thinning (un-thinned, moderate, and heavy) and pruning (low, medium, high) were tested. Growth characteristics, pilodyn penetration, and stress wave velocity were examined. Results showed that different thinning intensities significantly affected the mean annual diameter increment (F = 37.67; p < 0.01). The standing stock estimations of the thinning intensity regimes also significantly differed between different thinning intensities (F = 4.16; p = 0.035). Moreover, pilodyn penetration significantly varied with the thinning treatment (F = 23.53; p < 0.01). The stress wave velocity, however, did not significantly vary with the thinning treatment (F = 2.54; p = 0.11). Meanwhile, the effect of pruning treatment was not observed under all parameters. Heavy thinning treatment promoted all parameters except height and stress wave velocity. A strong positive correlation was observed between pilodyn penetration and DBH. This result suggested that thinning and pruning promoted positive DBH growth and an increase in the economic value of the stand, but it did not affect the wood properties of clonal teak wood.

Genetic diversity and structure among four provenances of Gelam (Melaleuca cajuputi subsp. cumingiana) and implications for gene conservation and rehabilitation of degraded peat swamp forest in Indonesia

Yayan Hadiyan,Widiyatno,ILG Nurtjahjaningsih,Mohammad Naiem,Bambang Herdyantara,Isno 한국산림과학회 2022 Forest Science And Technology Vol.18 No.4

Gelam (Melaleuca cajuputi subsp. cumingiana) is an important pioneer species of tropical peat swamp forests in Indonesia. We collected 95 DNA of dry leaf samples in four provenan- ces in Indonesia (South Sumatera, Bangka, South Kalimantan, Papua) and 8 SSR markers were used to analyze the genetic correlation and genetic diversity which plays an important role in providing survival, reducing inbreeding, and preventing inferior offspring to meet for- est rehabilitation needs. Our study revealed that the genetic diversity of gelam was compar- ably high due to geographical isolation and divided into five clusters. The genetic diversity among provenances and individuals within provenances was 7.11% and 14.85%, respectively. Papua showed the highest genetic diversity, based on the effective number of alleles, Shannon index, expected heterozygosity, allelic richness, and number of private alleles. The highest heterozygosity and rare alleles were found in South Kalimantan and Bangka. However, the coefficient of inbreeding was significant within provenances (p < 0.05) for all provenances, indicating inbreeding. We detected significant differences in heterozygosity using a two-phase model and a stepwise mutation model in a bottleneck test, although there was no significant difference when using an infinite allele model. These results suggest that the high genetic diversity among provenances could promote the future breeding pro- grams and develop conservation strategies for gelam.

Evaluation of Genetic Parameters of Growth Characteristics and Basic Density of Eucalyptus pellita Clones Planted at Two Different Sites in East Kalimantan, Indonesia

Alfia Dewi FADWATI,Fanny Hidayati,Mohammad Naiem 한국목재공학회 2023 목재공학 Vol.51 No.3

Eucalyptus pellita is one of the fast-growing tree species and has become predominant in Indonesian forest plantations. Meanwhile, tree breeding programs with clone development are the best way to provide greater genetic advantages. A better understanding of genetic control on growth and basic density in E. pellita is important for increasing wood productivity and quality. In this study, growth characteristics (tree height, diameter, and volume), basic density and its genetic parameters (heritability, genetic gain and genetic correlation) were determined. The number of clones tested in both trials was 50, divided into 5 blocks, and 5 trees/plot. The results showed that there were significant differences in growth and basic density among clones. There was an interaction between genetics and the environment further indicating the existence of unstable clones. The high heritability was found in tree height (0.82–0.86), diameter (0.82–0.90), and basic density (0.91–0.93). This implies that E. pellita has good opportunities for genetic improvement to increase wood productivity and quality. In addition, the results of genetic correlations among growth characteristics (height, diameter, and volume) and basic density showed positive moderate to highly significant value. It is suggested that these characters may be used to the advantage of the breeder for bringing improvement in these traits simultaneously. Therefore, this study provides important information of the genetic improvement of wood quality in E. pellita in Indonesia.

Selection of dipterocarp species for enrichment planting in a secondary tropical rainforest

Widiyatno,Fanny Hidayati,Suryo Hardiwinoto,Sapto INDRIOKO,Susilo Purnomo,Jatmoko,Naoki Tani,Mohammad Naiem 한국산림과학회 2020 Forest Science And Technology Vol.16 No.4

The selection of species for enrichment planting that involves native species in a secondary lowland dipterocarps forest as one of the tropical rainforest types should be conducted to maintain the sustainable management of tropical rainforests. The research of species trial of dipterocarp species was planted under a randomized complete block design with four repli�cations. The following parameters were examined: survival rate, diameter breast height (DBH), pilodyn penetration (PP), and stress wave velocity (SWV). The survival rate (F ¼ 1.72; p ¼ 0.047), DBH (F ¼ 6.67, p < 0.0001), and pilodyn penetration (F ¼ 14.19; p < 0.001) signifi�cantly differed at 12.5 years after planting. The survival rate of Shorea leprosula was the high�est (85%) of all the species, and the survival rate of other species, namely, S. macrophylla, S. ovalis, S. johorensis, S. scaberima, and S. parvifolia, was more than 70%. The best growth of DBH parameter was observed in S. platyclados. The DBH growth of S. platyclados 12.5 years after planting were 27.62 cm (mean annual diameter increment [MADI]¼ 2.2 cm/year). The species whose growth in DBH was similar to those of S. platyclados were S. leprosula, S. parvivolia, and S. ovalis. However, stress wave velocity (SWV) was not significantly different among dipterocarp species (F ¼ 1.26; p ¼ 0.234). Pilodyn penetration (PP) was significantly correlated with DBH (Pearson’s correlations ¼ 0.306; p < 0.001), whereas stress wave velocity was not significantly correlated with DBH and PP (p > 0.05), and their Pearson’s correlations were 0.043 and 0.012, respectively. These results suggested that each dipterocarp species varied in terms of their growth and wood properties. Thus, choosing the species for enrich�ment planting in secondary tropical rainforests depends on the characteristics of each spe�cies and the desired final product of forest management.

Effect of Improved Planting Stock on Tree Growth, Wood Properties, and Soil Fertility of Teak Plantations 10 Years After Planting

Widiyatno,Aris Wibowo,Dian Novitasari,Gama Widya Seta,Daryono Prehaten,Fanny Hidayati,Widyanto Dwi Nugroho,Suryo Hardiwinoto,Mohammad Naiem,Naoki Tani 한국산림과학회 2024 Forest Science And Technology Vol.20 No.1

Teak (Tectona grandis Linn. f.) is one of the most economically valuable types of tropical forest because teak wood has high durability, resilience and good aesthetic qualities. Teak tree improvement in Indonesia was initiated in 1983 producing planting stock for reforestation, i.e. clonal seed orchards (CSO) to produce seedling as sexual reproduction (referred to seedling), and hedge orchards to produce shoot cuttings as asexual (vegetative) reproductive (referred to shoot cuttings). Teak plantations established using seedling and shoot cuttings should improve forest productivity. The objectives of this study were to compare the growth rate, wood properties, and soil fertility of teak plantations propagated using seedling and shoot cuttings. Three square plots of 100 trees (10�10 trees; 1,000 m2) were established on both types of plantation and tree growth characteristics, wood properties, and soil fertility were monitored. The tree growth characteristics were diameter at breast height (DBH), tree height (H), clear bole height (CB), and volume of standing stock (Vss), and the wood properties included pilodyn penetration (PP) and stress wave velocity (SWV). Soil fertility was assessed from soil samples collected from three soil depths, with three replicates in each plot: 0–5 cm (top layer), 6–30 cm (middle layer), and 31–60 cm (bottom layer). Soil samples were analysed for total nitrogen, total phosphorus, total potassium, total calcium, and total magnesium. The results showed that the mean DBH, H, CB, and Vss differed significantly between the type of planting stock. The DBH, H, CB, and Vss values were 28.4%, 46.8%, 49.1%, and 130.1% higher, respectively, in teak plantations from shoot cuttings than from seedling. Moreover, the SWV of shoot cuttings planting stock plantation was 3.6% higher than from seedling. The mean PP did not differ significantly between teak plantations from shoot cuttings (22.00 mm) and seedling (21.80 mm). Furthermore, the planting stock did not affect soil fertility, which was highest in the top layer in all treatments. Our results suggest that teak plantations from shoot cuttings would increase growth, forest productivity, maintaining wood quality and soil fertility. Thus, it can maintain sustainable teak forest plantations.