Dody Priadi

Bio: Dody Priadi is an academic researcher from Indonesian Institute of Sciences. The author has contributed to research in topics: Pith & Falcataria. The author has an hindex of 4, co-authored 26 publications receiving 138 citations.

Variation in the wood properties of paraserianthes falcataria planted in indonesia

Abstract: In many tree breeding programs, plus trees have been selected according to growth rate or stern form in trees. Trees that have a high growth rate or good stern form do not always produce industrially desirable wood. Therefore criteria for wood quality should be considered in tree breeding programs. The objective of this study is to obtain the basic knowledge for breeding for wood quality in Paraserianthes falcataria, an important commercial tree species of Indonesia. Variation in the growth, log properties, basic density, and fiber length in 13-year-old P. falcataria was investigated. Even though all trees were the same age, diameter at breast height showed high variation, indicating a significant variance in the growth rate of seedlings. Significant differences in the log properties (green density, dynamic Young's modulus, and stress-wave velocity) were observed among the trees. Basic density showed a constant value up to 10 cm from pith, at which point it began to increase. The fiber length increased up to 10 cm from the pith and then showed an almost constant value. According to the radial variation of the basic density and fiber length, wood is categorized as core wood, which includes that up to 10 cm from the pith, and outer wood, which is that from 10 cm to the bark. In addition, a significant difference in the basic density of core wood was observed among the trees, indicating that the selection of a plus tree with high-density wood in this species is possible at a relatively early stage. These results indicate that the wood quality in P. falcataria can be improved through tree breeding.

Radial Variation of Anatomical Characteristics in Paraserianthes Falcataria Planted in Indonesia

Abstract: Radial variation in anatomical characteristics of five 13-year-old Paraserianthes falcataria (L.) Nielsen (syn. Albizia falcataria (L.) Fosberg), an important commercial tree species in Indonesia, were investigated in order to obtain basic information regarding breeding for wood quality. Both cell wall thickness in wood fibers and vessel percentage showed an almost constant value up to 10 cm from the pith and then increased toward the bark. In contrast, wood fiber percentage decreased from 10 cm toward the bark. The cell wall percentage was lower towards the pith and higher towards the bark. In the five sample trees, significant differences were found in the cell diameter of wood fibers, wood fiber percentage, axial parenchyma percentage, and cell wall percentage. Basic density was affected by the cell wall thickness of wood fibers, but not the vessel percentage and fiber percentage.

Radial Variation in Microfibril Angle and Compression Properties of Paraserianthes Falcataria Planted in Indonesia

Abstract: Paraserianthes falcataria (L.) Nielsen is an important plantation species in Indonesia. The objective of this study was to understand the radial variation of microfibril angle in the S2 layer of the wood fiber wall (MFA) in P. falcataria, and its relationship to compression properties parallel to the grain, including modulus of elasticity (E) and compression strength (σ). MFA gradually decreased from pith to bark while both E and σ increased from pith to bark. Significant differences in MFA, E, and σ were found among the five sample trees. Single-regression analysis of wood and compression properties revealed that the compression properties of core wood were affected mainly by density, whereas those in outer wood were affected by both MFA and air-dry density (AD).

Seedling Production of Pak Choy (Brassica rapa L.) using Organic and Inorganic Nutrients

Abstract: Pak Choy or Bok Choy ( Brassica rapa L. var. chinensis) is one of favorite Chinese leafy vegetable for various dishes in Indonesia. In this study, it was used as a plant model to identify the appropriate organic hydroponic nutrient solution for leafy vegetable seedling production. The seed was sown on rock wool slabs submerged with 200 ml of a nutrient solution containing biofertilizer of Beyonic StarTmik@Lob (0, 25, 50, 75, and 100%). commercial hydroponic solution (0, 25, 50, 75, and 100%) and its combination (25, 50, and 75%). The experiments were arranged in a CRD. Meanwhile, the obtained data was analyzed using ANOVA followed by DMRT. The relationship among growth parameters was observed using Pearson correlation analysis. The result of the study showed that the combination of organic and inorganic nutrient (25% Beyonic StarTmik@Lob and 75% commercial hydroponic solution) resulted in the highest seedling growth parameters and leaf indices as well as the perfectly positive correlations among growth parameters. This result indicated that the use of organic nutrient alone was not appropriate for hydroponic seedling production of Pak Choy. Therefore, further study needs to be done to identify the hydroponic solution without inorganic nutrients towards the organic vegetable production.

Cassava breeding and agronomy in Asia: 50 years of history and future directions

Abstract: In Asia, cassava (Manihot esculenta) is cultivated by more than 8 million farmers, driving the rural economy of many countries. The International Center for Tropical Agriculture (CIAT), in partnership with national agricultural research institutes (NARIs), instigated breeding and agronomic research in Asia, 1983. The breeding program has successfully released high-yielding cultivars resulting in an average yield increase from 13.0 t ha-1 in 1996 to 21.3 t ha-1 in 2016, with significant economic benefits. Following the success in increasing yields, cassava breeding has turned its focus to higher-value traits, such as waxy cassava, to reach new market niches. More recently, building resistance to invasive pests and diseases has become a top priority due to the emergent threat of cassava mosaic disease (CMD). The agronomic research involves driving profitability with advanced technologies focusing on better agronomic management practices thereby maintaining sustainable production systems. Remote sensing technologies are being tested for trait discovery and large-scale field evaluation of cassava. In summary, cassava breeding in Asia is driven by a combination of food and market demand with technological innovations to increase the productivity. Further, exploration in the potential of data-driven agriculture is needed to empower researchers and producers for sustainable advancement.

Prediction of the mechanical properties of lumber by stress-wave velocity and Pilodyn penetration of 36-year-old Japanese larch trees

Abstract: The objective of this study was to obtain basic knowledge for the prediction of the mechanical properties of Japanese larch lumber (Larix kaempferi) on the basis of tree properties, such as the stress-wave velocity (SWV) and Pilodyn penetration value (Py). The values of the correlation coefficient between the SWV of a standing tree and the dynamic Young’s modulus (DMOE) of logs, which were obtained at various heights, gradually decreased with an increase in the log sampling height, indicating that the SWV of a tree is affected by wood properties at the measuring position. A significant correlation between the SWV of trees and the average modulus of elasticity (MOE) of lumber was found (r =0.834). A significant negative correlation between the Py of a tree and the average modulus of rupture (MOR) of lumber was also found (r=-0.859). A high coefficient of determination for an obtained regression curve was found when both the SWV and Py of a tree were used for evaluating the average MOE or MOR of lumber. These results indicate that the average MOE and MOR of lumber can be predicted by using the SWV and Py of the Japanese larch tree.

Recent developments in sustainable arrowroot (Maranta arundinacea Linn) starch biopolymers, fibres, biopolymer composites and their potential industrial applications: A review

Abstract: Raising environmental awareness had forced researchers to explore the potential and implementation of environmentally friendly materials as alternatives for conventional materials. Environmentally friendly materials are biodegradable, safer, non-toxic, lightweight, cheap, and readily available. Arrowroot starch has a high content of amylose (~35.20%) which makes it suitable for better film production. Starch extracted from arrowroot rhizomes can be blended, plasticized with other polymers, or reinforced with fibres to improve their properties. The melt blended glycidyl methacrylate-grafted polylactide (PLA-g-GMA) and treated arrowroot fiber (TAF) treated with coupling agent developed PLA-g-GMA/TAF composite, which showed better properties than the PLA/AF composite. To the best of our knowledge, no comprehensive review paper was published on arrowroot fibres, starch biopolymer, and its biocomposites before. The present review focuses on recent works related to the properties of arrowroot fibres and starch, and their fabrication as biocomposites. The review also reveals the vast potential of arrowroot fibres and starch for food industries, medicines, textiles, biofuel, pulp, and paper-making industries, bioenergy, packaging, automotive, and many more.

Wood Density and Mechanical Properties of Pinus kesiya Royle ex Gordon in Malawi

Abstract: Successful development of an appropriate tree breeding strategy and wood utilization requires information on wood properties. This study was therefore conducted to assess wood density and mechanical properties of Pinus kesiya Royle ex Gordon grown in Malawi. Wood samples from six families of P. kesiya at the age of 30 years were used for the study. The estimated mean wood density, Modulus of Elasticity (MoE), Modulus of Rupture (MoR) and moisture content were 0.593 ± 0.001 g/cm3, 13.46 ± 0.07 GPa, 113.67 ± 0.57 MPa and 12.08% ± 0.03%, respectively. There were statistically significant (p 0.05) differences in wood density and mechanical properties among the families. This is an indication that any tree among the families can be selected for tree improvement programs if density is considered as a variable. Wood density had a strong positive significant linear relationship with both MoE (r = 0.790; p < 0.001) and MoR (r = 0.793; p < 0.001). This suggests that it has the potential to simultaneously improve the wood density and mechanical properties of this species. Therefore, controlling wood density for the tree improvement program of P. kesiya in Malawi would have a positive impact on mechanical properties.