Improvement of fermentable sugar yields of mangium through transgenic overexpression of xyloglucanase

Recalcitrance to saccharifi cation is a major limiting factor of the conversion of lignocellulosic biomass to ethanol. Levels of wood saccharification and subsequent ethanol production were higher in transgenic mangium (Acacia mangium) trees overexpressing xyloglucanase than in wild-type plants, even after delignification of the wood. We propose that a decrease in the quantity of xyloglucan that is intercalated into cellulose microfibrils could facilitate the process of saccharification.     

Effect of Paclobutrazol and Auxin on Growth Plantlet of Garlic Varieties in in Vitro Culture

Area of cultivating garlic in Indonesia experienced a sharp decline. In a period of 20 years （1991-2011）, the decline of garlic planting area reaches 91%. The fact is causing erosion of genetic resources of several varieties of garlic. Propagated vegetatively garlic through in vitro culture aims to obtain quality bulblet. This study aims to get the combination treatment between paclobutrazol, indole acetic acid （IAA）, indole butyric acid （IBA） and naphthalene acetic acid （NAA） in some varieties of garlic in Indonesia. This study used a completely randomized design （CRD） with two treatment factors, i.e., on varieties （Bali, Gunung Kidul, Slawi, Tawangmangu and Mataram） and 1.5 ppm paclobutrazol combination with a wide auxin （IAA 0.5 ppm, 0.5 ppm IBA, NAA 0.5 ppm）. Variable observations include the current appear shoots and roots, number of shoots and roots, shoots and root length. Observations showed that the combination of paclobutrazol ＋ NAA is able to produce plantlets that have the best vigor than paclohutrazol ＋ IAA and paclobutrazol ＋ IBA combination treatment.     

Growth characteristics, stress-wave velocity, and Pilodyn penetration of 15 clones of 12-year-old Tectona grandis trees planted at two different sites in Indonesia

Tree improvement programs for teak (Tectona grandis) have mainly focused on breeding of trees with superior growth characteristics. However, improvement in wood quality should be included in breeding programs for high yield and high quality timber. In the present study, growth characteristics [stem diameter (D), tree height (H), and bole volume (V)], stress-wave velocity (SWV), and Pilodyn penetration (Py) were measured for 15 clones of 12-year-old teak trees planted at two different sites in Indonesia to clarify the variations in tree growth characteristics, SWV, and Py among clones, their repeatability, interaction between genotype and environment, and correlations between measured characteristics. Significant differences of all measured characteristics were found among 15 clones at both sites. Their repeatability showed relatively moderate to high values in both sites. These results indicate that these characteristics are closely related to genetic factors. Significant interaction between genotype and environment was found in all measured characteristics. In addition, SWV and Py showed lower interaction between genotype and environment than growth characteristics. No significant correlation was found between growth characteristics and SWV. These results suggest that wood properties and growth characteristics of teak trees can be improved by application of an appropriate tree breeding program.     

Tree growth performance and estimation of wood quality in plantation trials for Maesopsis eminii and Shorea spp.

Plantations of tropical species are becoming an increasingly important source of wood.However, it is important that research trials focus not only on tree growth performance, but also on wood quality.The aims of this study were to assess the growth performance of six commercially and ecologically important tree species from separate plantation trials in Indonesia and to determine the relationships between tree growth and wood quality in terms of the dynamic modulus of elasticity(MOE) and wood density.Forty-eight 7-year Maesopsis eminii Engl.and thirty-five 9-year specimens(7 each of 5 Shorea spp.)were selected from two trials.The MOE, based on acoustic velocity, was indirectly measured to evaluate wood stiffness.Tree-growth performance was evaluated, and correlations between growth traits and acoustic velocity as well as density and wood stiffness properties were estimated.The growth performance of M.eminii in terms of tree volume was significantly different in three different categories of growth(i.e.fast, medium, slow).Of the five Shorea spp.studied, Shorea leprosula Miq.had the highest growth rate, as expected since it is known to be a fastgrowing Shorea species.Indirect measurement of wood quality by means of non-destructive ultrasonic methods showed a weak negative correlation between tree volume and acoustic velocity and dynamic MOE.Although each fast-growing tree could reach a merchantable size faster than other varieties or species, wood traits of various species tested were not significantly different based on tree growth rate performance.The findings from this study could be used to improve selection criteria in future breeding trials; indirect measurements of the dynamic modulus of elasticity can be used in mass pre-selection of genetic materials, to choose the most-promising material for in-depth evaluation.     

Quantifying the rare: Baselines for the endangered Napoleon Wrasse,Cheilinus undulatus,and implications for conservation

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Effect of three types of liquid compost combined with Avicennia marina leaves on growth and survival of tiger prawns (Penaeus monodon)

International Aquatic Research - The sustainability of prawn farming in brackish water ponds is controversial because of low yields and a history of mangrove clearing. Low yields are due largely to...     

Cytogenetic studies on the interspecific hybrid Capsicum baccatum L.× C. frutescens L. and its progeny

Summary Morphological and cytogenetical studies were carried out on the F₁ and F₂ hybrids and backcross derivatives of the interspecific cross Capsicum baccatum L. x C. frutescens L. The F₁ and F₂ hybrids displayed irregular meiosis with a maximum association of eight chromosomes in the former and one quadrivalent in the latter with the appropriate number of bivalents and univalents. It is inferred that C. baccatum differs from C. frutescens (yellow) by at least tow or three interchanges and from the white cultivar by a single interchange. Structural repatterning of chromosomes, erratic meiotic behaviour, genes for pollen sterility, segregational imbalances following intergenomic recombination are believed to be major factors causing sterility in the hybrids. The two species are sympatric and natural hybrids have not been realised.     

Effect of land degradation on soil microbial biomass in a hilly area of south Sumatra,Indonesia

We investigated the impact of land-use changes on the soil biomass at several soil sites in Indonesia under different types of land-use (primary forest, secondary forest, coffee plantation, traditional orchard, and deforested area), located within a small geographical area with similar parent material and climatic conditions. Various parameters of soil microbial biomass (biomass C, biomass N, content of anthrone-reactive carbohydrate carbon, and soil ergosterol content) were examined. Our results suggested that the removal of the natural plant cover did not cause any appreciable decrease in the amount of microbial biomass; on the contrary it led to a short-time increase in the amount of microbial biomass which may be due to the availability of readily decomposable dead roots and higher sensitivity to the decomposition of residual litter in recently deforested soils. However, the amount of microbial biomass tended to decrease in proportion to the duration of the land history in coffee plantation soils. This may be ascribed to the effect of the loss of available substrates associated with soil erosion in the long term. Lower ergosterol contents in recently deforested areas reflected a reduction in the amount of fungal biomass which may be due to the destruction of the hyphal network by the slash and burn practice. On the other hand, the higher soil ergosterol content at the sites under bush regrowth indicated that microbial biomass was able to recover rapidly with the occurrence of a new plant cover.