Climate change and human-centered development have endangered the survival of many species. The purpose of this study was to investigate, using MaxEnt, changes in the habitat suitable for the endangered palm Metroxylon vitiense (H. Wendl.) H. Wendl. ex Benth. & Hook. f. in Fiji resulting from a changed climate. MaxEnt is a maximum entropy-based machine learning program, and it can estimate the probability distribution for the occurrence of a species based on environmental constraints. The results indicated that precipitation in the driest month had the highest gain when it was considered in isolation, indicating that this factor is the most important environmental variable influencing the distribution of this palm. Moreover, precipitation in the driest quarter and annual precipitation may influence to some extent the distribution of the species. Predictions indicated that future suitable habitats for M. vitiense may occur not only in the coastal area, but also away from it. Although this prediction has associated uncertainty, the suitable area may increase to 409.7% and 240.9% of the area of current suitable habitats. The coastal area, where the current habitat it located, is subject to rapid development and may be affected by sea-level rise. In this case, ex situ conservation would be effective. In order to avoid risk, this study suggests that it would be appropriate to plant M. vitiense away from coastal areas. However, ensuring there is sufficient area for transplantation is a major issue.

Under high soil water levels, an imbalance occurs in the utilization of photosynthate between supporting vegetative growth and storage as starch. This results in a reduction in the density of dry matter in the stem and increased plant size. On the other hand, biomass yield and starch yield are considered to be low. This study examined the response of sago palm ( Metroxylon sagu Rottb.) seedlings to 50 and 80% soil water levels. To determine the response of the plant, several parameters were observed during the experiment: N, P, and K uptake, leaf photosynthesis, plant morphological growth, and sugar content in plants. It was found that the sago palm was able to show good growth performance under both 50 and 80% soil water levels. However, 50% soil water level is preferable due to trends in N, P, and K uptake, leaf photosynthetic rate, morphological growth performance, and also because no loss of starch is evident in the petiole or root.

Sago palm (Metroxylon sagu Rottb.) photosynthetic performance was evaluated under drought conditions through leaf gas exchange and chlorophyll a fluorescence measurement. Drought has an impact on sago palm’s leaf gas exchange parameters and its chlorophyll fluorescence of PSII. Stomatal limitations were found to be the main factor limiting photosynthetic activities of sago palm under drought conditions. Photosynthetic rate decreased following the inhibition in the PSII reaction center. Early detection of interference upon the efficiency of the PSII reaction center due to drought stress was recorded by chlorophyll a fluorescence measurement.

Sago palm (Metroxylon sagu Rottb.) is distributed in Southeast Asia and Melanesia, and it produces comparatively high yield of starch (more than 200 kg per plant). This species can grow in wetland swamps where other food crops cannot grow economically and adapt to problem soils such as acid or saline with low input. The Society of Sago Palm Studies and the authors have published books entitled “The Sago Palm: The Food and Environmental Challenges of the 21st Century (Kyoto Univ. Press 2015)” and “Sago Palm: Multiple Contributions to Food Security and Sustainable Livelihoods (Springer 2018)”. This paper provides a brief review on (1) characteristics of seed germination and preparation of planting materials utilizing germinated seeds, (2) symbiosis of sago palm and microbes (nitrogen fixing bacteria or arbuscular mycorrhizal fungi), (3) creating new value from pith waste after conventional starch extraction (recovery of starch, ethanol production or preparation of biodegradable foam from the waste) and (4) utilization of leaf or bark from our former publications and the achievements published in our journal ‘SAGO PALM’ or the proceedings of the International Sago Symposium to discuss sustainable production and utilization of sago palm resource in Asia and Pacific.

The role of sago palm is considered highly important in providing income and food for the local community of Luwu Utara. This study examines farmers’ willingness to plant sago palm. The result indicated that majority of respondents want to plant sago palm (75%). The data also revealed the majority of the “unwilling” respondents do not want to plant sago palm because they do not have a planting area (96%), whereas the “willing” respondents possess a sago plantation area (70.7%). The farmer`s age, work experiences, sago area, and employee ownership show a significant relationship with behaviour to plant sago palm. Introduction Numerous attempts have been made to develop cultivation of sago palm at the industrial level, but to date there has been no significant development even though sago has been recognized as a valuable resource since the early 1970s (Regional Research and Development Agency, 2008). One critical aspect of developing the sago palm industry is the requirement to adopt practicable technology for production and management systems (Laufa, 2004) especially for smallholders. Sago farmers, especially in Indonesia, are still using conventional practices in sago processing and do not know how to cultivate sago palm. Osozawa (2016) argued cultivation at the farmer level is difficult because sago plants are large, much bigger than a human body. The farmers are familiar with cultivating cereals, tubers, and vegetables, which are small. In addition, at the national level, there is no long-term comprehensive strategy that includes developing or promoting sago palm (Trisia et al., 2016).

The genus Vigna contains important crops such as cowpea and mungbean. Wild Vigna showing higher salt tolerance than Vigna crops were screened and their tolerance mechanisms are discussed. Primary screening using 7 Vigna crops and 23 wild Vigna under 300 mM NaCl selected V. luteola, V. marina and V. vexillata. A study under different salt concentrations revealed the highest survival ability of V. marina. Diversity of salt tolerance in each species was revealed using a total of 230 accessions. Growth and physiological responses under 150 mM NaCl were then compared using two selected accessions from each species. The pattern of Na+ accumulation in roots, stems and leaves suggested that V. vexillata (V1) and V. luteola (L8, L9) are ‘Na+ excluder’ type, while V. marina (M1, M4) is ‘Na+ includer’ type. V. luteola (L8, L9) showed the highest dry matter production under control condition and well-maintained shoot dry weight under salt stress. Interestingly, V. luteola (L9) accumulated the highest Na+ in roots (3000 μM g−1) and increased root dry weight under salt stress, which might work as Na+ reservoir restricting Na+ transition to the leaves, leading to the increased photosynthetic rate. V. luteola has great potential in areas where moderate salt damage occurs. V. marina (M1, M4) accumulated Na+ at high level in roots, stem, and leaves. Under salt stress, they increased stomatal conductance, transpiration rate, and photosynthetic rate, which suggested the adaptational regulation of aquaporin gene expression. V. marina will be useful as food, pasture and phytoremediation legumes in highly salt-damaged areas.

Photosynthetic performance of sago palm (Metroxylon sagu Rottb.) was evaluated in normal and waterlogged conditions. Net assimilation rate (AN), light response curve of net assimilation rate (AN/I) and pulse-amplitude modulation fluorescence vs. irradiance (PAM/I), leaf water potential, leaf chlorophyll content and leaflet area were measured. AN was higher in a particular period of waterlogging than in the normal condition. However, prolonged waterlogging (more than two months) negatively affected sago palm photosynthetic capacity. This was indicated by reduction in several photosynthetic parameters such as AN, maximum value of AN obtained at maximum irradiance (AN (Imax)), quantum yield at zero to 200 µmol m−2 s−1 irradiance (ϕ(Io_I200)), asymptotic photosynthetic efficiency (αo), and maximum electron transport rate (ETRmax). The plants experiencing waterlogging produced high qNmax and NPQmax values. Prolonged waterlogging period also caused significant reduction in leaf water potential (ψleaf) and photosynthetic pigments content. Normal soil conditions with a sufficient amount of water are preferable in order for the plant to generate higher photosynthetic capacity and facilitate stable sago production.

Photosynthetic activities of the sago palm (Metroxylon sagu Rottb.) were studied to find out its sensitivity to changes in ambient air temperature. The minimum ambient air temperature designed for the experiment was 25–29 °C, while the higher end was 29–33 °C. Several photosynthetic parameters were studied to support our analysis in sago photosynthetic activity, including diurnal leaf gas exchange, assimilation rate vs. CO2 concentration, leaf greenness, leaf chlorophyll content, and photosynthetic rate vs. irradiance. We found that sago palm photosynthetic activity tends to be more sensitive to minimum than to maximum ambient air temperature. The plants exposed to higher air temperatures had dark green leaf color associated with higher rates of diurnal photosynthesis, chlorophyll content, and rubisco limited photosynthetic activity. They also exhibited higher trend in optimum irradiance absorption level. Consequently, maximum light energy dissipation occurred at higher temperatures.

Three levels of aluminum concentration (AlCl3・6H2O) were added to a Kimura B culture solution: 0, 150, and 300 ppm with 3 replications. The culture medium pH of all treatments was adjusted to 3.5. There were no differences in plant height, plant length, or base diameter among the three treatments. No significant difference was seen in the leaf number per plant, leaflet number per plant, leaflet number per leaf, or number of emerged leaves per plant among the three treatments. Root diameters and dry matter weights of roots and whole plants were significantly higher in non-Al-treated (0 ppm Al) sago palms. The number of dead leaves, SPAD value, and chlorophyll content were significantly higher in Al-treated (150 and 300 ppm Al) sago palms. The dry matter weight of leaflets, petioles, and bases were not significantly different among the three treatments. There was marked significant difference in the total leaflet area per plant between 0 and 300 ppm Al. The difference in a single leaflet area was negligible among the three treatments. The relative growth rate (RGR) and net assimilation rate (NAR) tended to be slightly deceased with Al treatments; however, the leaf area ratio (LAR), specific leaf area (SLA), and leaf weight ratio (LWR) showed same levels in all three treatments. Stomatal conductance was significantly lower in Al-treated than in the non-Al-treated sago palms. The photosynthetic rates and transpiration rates were not significantly different with the three treatments. Moreover, the uptake of P, Ca, and Mg was interrupted in the Al treatments; however, N and K uptake were not affected by Al treatment. The root color darkened with Al treatments, and was more distinct with higher Al concentrations. There was a significant difference in the number of root cells per mm2 in the transverse section. From these data, it was clear that sago palm seedlings did not show obvious differences in morphogenesis of the top parts; however, its root diameter and cell differentiation in the cortex of the root were inhibited by high Al concentrations in the media.

The objective of this study was to investigate sago starch recovery from sago pith waste using wet milling, and to examine the sago starch physical properties. The results show that recovery of sago pith waste by wet milling increased the amount of starch by 21% (dry basis). Scanning electron microscopy showed that wet milling did not change the smoothness of the granule surface, and birefringence was clearly seen when the sample was observed using polarized light microscopy. The volume-median diameter of wet-milled sago starch was slightly higher than that of untreated sago starch; however, the particle size distribution index (span) was the same. X-ray diffraction showed that the crystallinity of wet-milled sago starch was similar to that of untreated sago starch. Differential scanning calorimetry showed that the peak temperatures and gelatinization enthalpies of untreated sago starch and sago starch milled using a super mass colloider were the same. These results show that wet milling is better than dry milling of sago starch, and does not much change its physical properties. Index Term-wet milling, sago pith waste, sago starch,

In this study, we extracted sago starch from sago pith waste (SPW) using a micro powder mill. The objectives were to recover the starch from the SPW and to understand the effects of micro powder milling on the physicochemical properties of micro-powder-milled sago starch. Milling was performed at different levels of disc clearance. Native sago starch extracted from sago pith, called untreated sago starch, was used as a comparison. The results show that micro powder milling of SPW can increase the sago starch yield by around 10‒17%, depending on the milling disc clearance. The amount of soluble starch in the SPW after micro powder milling was low for all treatments. The sago starch size distribution was wider at narrow clearance, but similar at wide, wide-medium, and medium-narrow clearances. Scanning electron microscopy showed that a narrow clearance treatment reduced the smoothness of the granule surface, and also reduced the starch granule birefringence. X-ray diffraction showed that the crystallinity decreased with decreasing milling clearance. Differential scanning calorimetry showed that the peak temperatures were similar at all levels, and the gelatinization enthalpy declined with decreasing crystallinity. The results suggest that sago starch can be recovered from SPW using micro powder milling, and the treatment, especially at narrow clearance, disrupts the crystalline regions of sago starch.

The growth response, nutrient concentrations in different plant parts and some physiological features under Al treatment were investigated to evaluate the Al resistance of sago palm under acidic conditions. Seedlings at the 7th leaf stage were used for the treatment of 0, 10, 20, 100 and 200 ppm Al in culture solution at pH 3.6 for 4.5 months. The study revealed that the growth of sago palm increased at low Al concentrations in the growth media under acidic conditions. This result might be attributed to a positive effect on the uptake of major nutrients, such as P, N and Ca 2+ . Nevertheless, the total dry weight and leaflet area significantly decreased under the 200 ppm Al treatment. This result might be associated with a significant decrease of the Ca 2+ and Mg 2+ uptake. The critical value at which the growth of sago palm was inhibited is considered to be approximately 200 ppm Al in the growth media. In addition, sago palm maintains a low Al 3+ concentration in the leaflets by storing Al 3+ mainly in the roots, especially in the lateral roots, and the Al 3+ concentration in the whole plant did not increase significantly even under the 200 ppm Al treatment. We conclude that Al resistance of sago palm might be due to the avoidance mechanism via the Al exclusion ability under acidic condition. Keywords : acidic condition; aluminum resistance; nutrient accumulation; physiological characteristic; sago palm.

Sago palm (Metroxylon sagu Rottb.) grows in natural peat swamps, which are poorly drained and has high acidity and generally contain highly exchangeable Al. It is, therefore, considered to be acidand Al-resistant. In this study, the growth, physiological characteristics and nutrient concentrations in the plant tissues of sago palm grown under a hydroponic system were investigated for 4.5 months. When sago palm seedlings were cultured at pH 5.7, pH 4.5 and pH 3.6, the leaf morphogenesis, nutrient uptake and dry matter production were maintained regardless of a small decrease in the photosynthetic rate through the decrease of stomatal conductance. In the case in which seedlings were grown at pH 3.6 with different levels of AlCl3·6H2O corresponding to 0, 10, 20, 100 and 200 ppm Al, the plant length and dry matter production increased with a mild Al concentration in the growth media, such as 10 ppm Al. This result was attributed to the increase in the P and N uptake. In contrast, all the growth parameters significantly decreased under the 200 ppm Al treatment. The critical value to inhibit the growth of sago palm was considered to be around 200 ppm Al in the growth media. In addition, sago palm maintained a low Al 3+ concentration in all of the plant parts. Therefore, it could be concluded that sago palm has high resistance to Al with mechanical restriction of the excess Al based on the Al exclusion ability under the acid condition.

Sago palm (Metroxylon sagu Rottb.) distributed in Southeast Asia and Melanesia grows in swampy, peaty, and alluvial soils in areas with both fresh and brackish water where almost no other crops grow without drainage and/or soil improvement. This palm species stores a large amount of starch in the trunk. The starch of sago palm is processed into various basic raw materials and is receiving attention as a sustainable energy resource as well as for use in the production of bioethanol due to the current situation, in which competition between biofuel and food production is taking place. However, sago palm is harvested primarily from natural forests and is considered to be an unexploited plant. Thus, the Na + and some other ion concentrations in different plant parts as well as the physiological and morphological features under NaCl treatments (86 to 342mM NaCl for 1 or 4 months in a hydroponic system) were investigated to study the salt resistance mechanism of sago palm to develop a sustainable method of cultivation that is essential for the improvement of sago palm as an economic plant. (1) Sago palm maintained a low Na + concentration in the leaflets, which may be attributed to Na + storage mainly in the roots. K + absorption and distribution to the leaflets may not be affected by changes in the Na + concentration in the roots and petioles in sago palm. (2) Based on X-ray micro-analysis, a dense distribution of Na was observed around the endodermis of the adventitious roots. Salt resistance of sago palm might be due to salt avoidance to mechanically restrict an excess of Na distribution in plant tissues as well as maintain the water status in the leaves by restricting the transpiration. (3) The development of Casparian strips in the endodermis can be considered as an important mechanical factor relating to the avoidance mechanism for preventing the excess influx of Na + into the stele and its translocation from root to shoot in sago palm. (4) The factor limiting the photosynthetic rate under NaCl stress was the reduction in stomatal conductance that resulted from a trade-off with the decrease in the transpiration rate to maintain the water status in the leaves. (5) Although chlorophyll production was depressed, the absorption of macronutrients was not inhibited by salt stress and there was no lack of materials, such as N and Mg for chlorophyll production. The chlorophyll concentration could increase up to high levels over a comparatively long time. These factors may account for the resistance of sago palm to salt stress and its ability to grow even with a reduction of the growth rate.

There are several types of Sorghum such as grain type, forage type, sudangrass and sorghum-sudangrass hybrid. Feeding values including chemical composition and rumen degradability characteristics would be varied among these different types. The objectives of this study were to determine the chemical composition, in vitro rumen degradability, gas production (GP) and volatile fatty acid (VFA) concentration among various varieties of Sorghum plants. Twenty-two cultivars of Sorghum consisted of three forage sorghum, two grain sorghum [S. bicolor (L.) Moench], two sudangrass [S. sudanense Stapf], and 15 sorghum-sudangrass hybrids were grown and harvested at 88 days after planting. Significant difference in dry matter yield was observed and ranged from 46.1 to 146 g plant -1 DM. The crude protein (CP) content averaged 57.9 g kg -1 DM, contents of neutral detergent fiber (NDF) ranged from 531 to 750 g kg -1 DM, acid detergent fiber (ADF) ranged from 250 to 411 g kg -1 DM, acid detergent lignin (ADL) ranged from 41.8 to 75.4 g kg -1 DM. Compared to fiber fractions, non-fiber carbohydrate (NFC) and soluble sugar contents were highly variable (91 to 318 g kg -1 DM and 17.1 to 94 g kg -1 DM, respectively). The in vitro organic matter degradability (IVOMD) at 96 h was different among cultivars ranged from 41.9 to 53.0%. Sorghum-sudangrass hybrids (HB) and non-hybrid types (non-HB) were not apparently different in the dry matter yield and morphological composition, and chemical composition. While the comparison between HB and sorghum type (forage and grain) were different in the yield and some morphological composition but no difference in the chemical composition. The contents of soluble sugars in Sorghum plants was positively correlated to the in vitro ruminal GP at early phase of incubation (0-9 h) (r = 0.87). Sugar contents were also highly correlated to cumulative GP and VFA concentration (r > 0.67) compared to IVOMD (r = 0.42), whereas ADL content had a negative relation to IVOMD (r = -0.70). The fiber contents (NDF or ADF) showed no relation between IVOMD and rate of GP (24-96 h). It was concluded that among various Sorghum plants, cultivars that maintained higher dry matter yield and degradable dry matter yield as well as higher sugar or lower ADL contents should be selected as ruminant forages.

Young seedlings of 22 Sorghum cultivars including sorghum, sudangrass and sorghum-sudangrass hybrids, were examined for their growth characteristics and sodium ion accumulation in different plant parts, under salt treatment. The salt treatment was started with 100 mM NaCl and increased to 150 mM during the experiment. The plant dry weight decreased under NaCl treatment in all cultivars, and especially the dry weight of leaf blade decreased markedly. The cultivar difference in the plant dry weight under salt stress was affected by that in relative growth rate which was mainly changed by net assimilation rate (NAR). Cultivars that maintained higher NAR under salt stress had a smaller specific leaf area and higher nitrogen content per unit leaf area. Sorghum plants under salt stress retained Na+ mainly in roots preventing the distribution of excess amount of Na+ to leaves, but the root dry weight was increased by salt stress. It was therefore considered that thicker leaf blades and apparent increases in root dry weight were the main contributors to the maintenance of dry matter yield and enhanced the growth of Sorghum cultivars under NaCl treatment.

The dry matter production, photosynthetic characteristics and nutrient concentrations in the plant tissues of sago palm seedlings cultured for 4.5 months in a hydroponic system at pH 5.7, 4.5, and 3.6 were examined. Plant growth in weekly increment of length, leaf emergence, leaf senescence, and total leaflet area was similar at all pHs. There was no significant effect of pH on the dry matter weight, although it tended to be lighter at pH 3.6 than at pH 5.7. Similarly, the photosynthetic rate and its related parameter were not significantly affected by the pH. However, the photosynthetic rate at pH 3.6 tended to be lower than that at pH 5.7, which was attributed to a decrease in the stomatal conductance. The effect of the low pH on the nutrient concentration in plant tissues was not distinct. We concluded that sago palm seedlings could maintain leaf morphogenesis and nutrient uptake in growth media at a pH ranging from 5.7 to 3.6 For 4.5 months, which led to a high growth rate and maintenance of dry matter production even at pH 3.6.