Sago (Metroxylon sagu Rottb.) is widely grown in the Philippines in waterlogged areas or near creeks and water embankments. The utility of the crop varies. Leaves are formed into shingles and used as roofing materials; leaf stalks are dried and used as firewood or fence material; the bark is dried for fuel wood; and the pith is extracted with the starch, roasted, and sold in the market in a dried and crumbly form that can be processed further into various foods. The traditional method of starch extraction requires at least 22 steps beginning with the harvest of the logs. It involves knife-stripping, drying and series of hand pounding and subsequent screening to reduce the size prior to sedimentation. The whole process is tedious and timeconsuming. Processing one whole sago log is estimated to require 10-12 man days and 5 to 6 days to completely extract the starch. The entire process was studied, and a sago-pith grating machine was developed.
 The developed grating machine eliminates the bottlenecks of the traditional starch extraction process, namely; knife-stripping, sun-drying of the stripped pith and repeated hand pounding and subsequent screening of the powdered pith. The number of steps in the traditional starch extraction process was reduced by as much as 50%. Splitting the sago logs into quarters is required prior to sago-pith grating. About 60-65 seconds is required to split a 32-cm diameter x 50-cm length sago log into four pieces. Only one person is needed to operate the machine with a grating capacity of 155 - 180 kg/hr depending on the skill of the operator. The parts of the machine utilized local and commercially available materials for easy repair and maintenance.

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 Sago palm (Metroxylon sagu) plants grown in a soil culture of 5 L plastic pots were dipped into 6 L plastic pots with a culture solution containing sodium chloride (NaCl) at a concentration of 0, 10, 50, 100, 200 or 400 mM to provide salt stress. The growth parameters, the water potential in sago leaflets, proline (Pro), glycinebetaine (GB), soluble chloride ion (Cl⁻), total sodium ion (Na⁺) and potassium ion (K⁺) in sago leaflets and roots were measured to evaluate the response of sago palm to NaCl stress. The exchangeable Na⁺ and K⁺ concentrations in soil were also determined to estimate the uptake by sago palm. The greatest growth was obtained in the 10 mM NaCl culture solution, based on the growth parameters and water potential in sago leaflets, which implied that sago palm requires a small amount of NaCl for vital growth. Pro was under the detection limit in leaflets and roots. However, a small amount of GB production was found in leaflets. Soluble Cl⁻ concentrations in leaflets increased exponentially with an increase in NaCl concentrations. Na⁺ was exponentially accumulated up to 100 mM in the roots and was not transported to the leaflets, indicating that sago palm can uptake and store Na⁺ in roots using a regulation mechanism to maintain the appropriate Na⁺concentration in leaflets. In addition, sago palm was able to uptake K⁺ from the soil culture, and K⁺ was accumulated in leaflets through the root systems in response to NaCl stress.

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 Various parts (root, rachis, petiole, leaflet, bark, and pith) of the sago palm were collected in the Phillipine islands of Leyte, Cebu, and Aklan, and their nitrogen-fixing ability was measured with an acetylene reduction assay (ARA). Almost all the samples, except for the leaflets, showed positive ARA activity ranging from 1.1 to 961 nmol g^-1day^-1. Among the samples, roots collected during July, 2003 showed the highest activity, followed by the pith. ARA activity in the petiole, rachis, and pith samples was quite variable. Some parts showed high activity, while others showed very low activity, suggesting a heterogeneous distribution of the nitrogen-fixing potential. Nitrogen-fixing bacteria (NFB) were then isolated by aerobic cultures using a N-free Rennie semi-solid medium from the samples showing high ARA activity. A homology search of 16S rDNA sequences revealed that the nitrogen fixers belonged to various genera, such as Klebsiella pnuemoniae, Pantoea agglomerans, Enterobacter cloacae, Burkholderia sp., and Bacillus megaterium. Some of the Gram-negative strains were confirmed by physiological tests using API20E and API20NE, while the physiological identification and 16S rDNA sequence did not match in a few strains. The relationship between the ARA of the isolates and their carbon sources showed that all the isolates preferred simple sugar compounds, such as glucose, sucrose, and mannitol, but showed very low activity in pectin, starch, and hemi-cellulose media. This study demonstrated the extensive colonization of sago palms by various types of nitrogen-fixing bacteria for the first time.

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