SAGO GETO LOH
Sago natural food The valid scientific name for sago is Potamogeton pectinatus, assigned by Linnaeus in his Species Plantarum of 1753. The name Potamogeton is derived from the Greek for "river neighbor," and the specific epithet pectinatus ("comb-like") derives from the closely set insertion of the plant's leaves. The synonyms P. interruptus Kit., P. latifolius J. Robbins, P. flabellatus Bab., and P. columbianus Suksdorf have been used in North American botanical texts. Many other synonyms have used in Europe. Two modern treatments, Kartesz and Kartesz (1980) and United States Department of Agriculture (1982), recognize 40 and 35 North American species of Potamogeton, respectively, and place the genus in the family Potamogetonaceae. Earlier, the genus had variously been placed in the families Zosteraceae and Najadaceae (Fernald 1950). There are about 100 species of Potamogeton world-wide (Kadono 1982). Sago flowers and leaves are simple and anatomically reduced, compared to those of other family members (Sculthorpe 1967). Sago was one of the first Potamogetons to be described. An illustration of "fennel-leaved water milfoile" is easily recognized as sago in the ancient herbal of John Gerarde (Johnson 1633; Moore 1915). An excellent history of the genus is available (Moore 1915).
Colloquial names for sago in the United States include duck grass, duck moss, eelgrass, fennel pondweed, foxtail, Indian grass, old-fashioned bay grass, pondgrass, potato moss, and wild celery (McAtee 1939). In Europe, sago has been called poker and pochard grass (McAtee 1917) and, in Australia, string weed (Fletcher et al. 1985).
In North America, sago is placed with P. filiformis and P. vaginatus in the subgenus Coleogeton, in which all leaves are linear or setaceous, nonfloating, and divided their full length by crosspartitions (Fernald 1950). Harrison (1949) claims members of this subgenus are, unlike others, water pollinated. The three coleogetonous species have also been shown to form a distinct subgroup based on the chemistry of the waters they inhabit (Pip 1987). In the field, sago can be differentiated from the two other coleogetonous species by the presence of usually sharp-tipped or gradually pointed leaves and leaf sheaths that are rather narrow but free at the tips.
Sago has an average of 2n = 78 (70-87) chromosomes (Kalkman and Van Wijk 1984). Analyses of isoenzymes indicated that the species is genetically very heterogeneous (Hettiarachchi and Triest 1986; Van Wijk et al. 1988). Sago hybridizes with Potamogeton filiformis (P. x suecicus Richt.) and P. vaginatus (Hagstrom 1916; Dandy and Taylor 1946; Harrison 1949). Meriaux (1978) and Van Wijk (1988) reviewed the work of many European taxonomists who named many varieties or "proles" of sago (dichotomus Wallr., drupaceus Koch, flabellatus Crep., interceptus Asch., protensus Wallr., setaceus Mey., scoparius Wallr., vulgaris Cham. and Schl., and zosteraceus Fries). Both questioned whether these are simple morphs or truly have value as indicators of specific biotopes or habitat types. Luther (1951, cited in Van Wijk 1983) also concluded that the different types of sago were habitat modifications. The varieties interruptus Asch., pectinatus, and scoparius have been maintained in a recent European flora, although their taxonomic validity is said to be unclear (Casper and Krausch 1980, cited in Van Wijk 1988). Van Wijk (1983) found different morphological and ecological characteristics of annual and perennial P. pectinatus in the field and in cultured plants and recommended that the existence of these ecotypes be considered when studying the taxon. Wiegleb (1978) associated the variety scoparius with HCO3-poor waters and the variety interruptus with sites polluted with sewage. Recent work has shown that genetic differentiation does occur in sago and must be considered along with morphological characters if the taxonomy of the species is to be clarified (Van Wijk et al. 1988).
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Autoecological Classification
Sago is one of only three or four North American species of Potamogeton that bear starchy underground perennating organs called turions or tubers, although a few other species have tuberous rootstalks. Sago is generally classified as a ruderal (capable of occupying mechanically disturbed areas), has multiple regenerative strategies, and is a stress tolerant, competitive plant that, depending on exposure to wave action, can alter its allocation of resources to different reproductive organs (Grime 1979; Kautsky 1987). In growth form, sago is considered a parvopotamid--that is, a higher aquatic plant rooted in sediment, perennially submersed except for inflorescences, and possessing long stems and small, mostly undivided, leaves (Hutchinson 1975). Luxuriant parvopotamid growth results in dense leaves, branches, and inflorescences in the upper part of the water column, with much thinner vegetation of stems and widely spaced leaves below; vegetation density of the upper part increases as water levels drop (Verhoeven 1980a).
Meriaux (1978) reviewed the work of devotees of the Zurich-Montpellier school of phytosociology (Braun-Blanquet 1932) who placed sago in various orders, alliances, and associations with other species in this elaborate phytosociological classification system. Sago was also recognized as a character or dominant species in several European and Asian associations by Hejny and Husak (1978). Sago is the most prominent plant in the Potamogeton facies of several estuarine plant communities in Europe (Kornas et al. 1960) and a faithful taxon in the class Potamea (den Hartog and Segal 1964) in some wetlands in India (Zutshi 1975). Sago also is a member of several Chara-, Ruppia-, and Zannichellia- dominated communities in the Baltic, Mediterranean, and Eurosiberian regions (Lindner 1978; Verhoeven 1980a; Van Vierssen 1982a).
Sago can be considered a pioneering species, because it quickly inhabits newly flooded areas (Nelson 1954) and invades shallow waters with relatively strong wave action (Ozimek and Kowalczewski 1984) or those that are polluted (Haslam 1978). Sago is one of the first species to colonize areas reclaimed from the sea (Wolseley 1986). den Hartog (1963) and Van Vierssen (1982a) considered sago a survivor species that often showed mass development in areas where the environment became temporarily unsuitable for other species. Davis and Brinson (1980) placed sago in a group of plants tolerant of, and able to maintain dominance in, altered ecosystems.
Sago is found in submerged, floating-leaved, and emergent communities. Best plant development occurs in submerged communities, and the poorest in emergent communities where sago plants tend to be short in stature (Van der Valk and Bliss 1971). In general, most other growth forms of hydrophytes, except similar types such as charids, valisnerids, and ceratophyllids, negatively influence the environment for parvopotamids, usually because of competition for light (Hogeweg and Brenkert 1969).
Most submersed macrophytes are sensitive to frost damage (Lohammar 1938). This, combined with the rapid decomposition of plants in water, causes sago to usually behave as an annual in shallow waters in temperate climates, with buried turions the only vegetative structure to survive winter (Lapirov and Petukhova 1985). However, green sago shoots can be collected under winter ice, presumably in deeper waters (Hammer and Heseltine 1988). Turions are perennial diaspores formed underwater and take several weeks or months to develop. The fruit-like seed (drupelets) can require a stratification period to germinate well in areas of fairly mild climate. These findings, plus the observation that sago could not compete well in shallow water against species that produce seeds (annual diaspores) more quickly, led Van Vierssen and Verhoeven (1983) to consider sago a species rather intolerant of habitat desiccation.
In mild climates sago can be evergreen (Spence et al. 1979b). Rarely, some deepwater forms of sago grow perennially from submersed rootstalks and can also have green shoots that survive winter (Moore 1915). Sago can behave as an annual by dying under conditions of high salinity and regenerating from drupelets when salinity decreases (Congdon and McComb 1981). When sago is compared to Potamogeton nodosus, a species that forms winter buds rather than turions, both species invest about the same amount of photosynthate in perennating structures, but sago produces about twice as many propagules (Spencer and Anderson 1987).
The functional aspects of sago's ability to thrive and survive in a wide variety of environments have been addressed in detail by Van Wijk (1988) and will be discussed in later chapters. Van Wijk (1988) points out the confusion that has resulted from use of the terms annual and perennial to categorize plant types as well as life-cycle types, and argues that they should only be used to indicate life cycles of populations without implying a classification of plant species. Under this system, sago could theoretically be said to have an annual life cycle with either (1) generative reproduction by seeds or vegetative reproduction by turions or thickened rhizomes or (2) a perennial life cycle with vegetative reproduction by whole plants or shoots. Not all of these strategies have been observed in nature.
In Europe, the Potamogeton pectinatus association is often linked to brackish water (den Hartog 1963) and inland marshes and depressions affected by mineral pollution (Meriaux 1978). den Hartog (1981) placed sago with a small group of plants that share many properties with marine angiosperms but cannot compete well with them except under special circumstances. He termed sago a member of the eurysaline group of plants in that they are able to tolerate waters from fresh to hyperhaline that vary greatly in chemical composition. These plants are also able to withstand rapid and considerable fluctuations in salt content of the waters they inhabit., Iversen (1929) included sago in a group of species restricted to alkaline waters. Lohammar (1938) found sago in lake waters characterized by both high pH and calcium content. Further analysis of Lohammar's data by Hutchinson (1975) showed sago to be a eurytopic species able to tolerate a wide range of nutrient (nitrogen, phosphorus) concentrations. Moyle (1945) placed sago in an assemblage of hard water species able to withstand waters high in sulfate ion. Other classifications based on water chemistry have been proposed by Spence (1967) and Seddon (1972).
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Distribution
Unlike most of the Potamogetons, which are interior and northern in global distribution, sago is nearly cosmopolitan (St. John 1916). The plant occurs circumboreally to about 70° N (Hulten 1968) and can also be found in South Africa, South America, South Eurasia, and New Zealand. The species occurs from sea level to nearly 4,900 m above sea level in high mountains of Venezuela and Tibet (Ascherson and Graebener 1907, cited in Yeo 1965). Pip (1987) recorded 19 species of Potamogeton at 430 wetland sites distributed throughout a large area of central North America and found sago second only to P. richardsonii in frequency of occurrence.
A researcher from Aklan State University (ASU) in Banga, Aklan, has ,found an easy way to germinate sago palm (Metroxylon sagu) seeds for planting. Previously people found it hard to germinate seeds of this palm species which yields valuable flour as well as leaves for roofing.
He is Michael Ibisate, research coordinator of the ASU’s College of Agriculture, Forestry and Environmental Sciences, who said that sago seeds easily germinate when soaked in a swampy and muddy environment provided that they are physiologically mature.
In his experiment, Ibisate simulated the environment which favors seed germination. This resulted in one hundred percent germination of mature sago seeds after one month, he said.
Ibisate, who has been working on the conservation of sago palm using tissue culture technique, said in their previous study that the sago seed was believed to have poor germination due to the presence of pericarp and sarcotesta. Thus, his research team used embryo rescue technique which enabled the successful development of an immature or weak embryo into a viable plant in vitro.
Aside from tissue culture, sucker is the widely used planting material for mass propagation of sago palm. In this regard, ASU researchers are planning to study further the use of sucker as planting material to determine the optimum conditions required to reduce mortality rate at seedling stage.
Sago, locally known as Ambolong in AkIan, has enormous starch deposit in its trunk. The starch has a high food value and has a big potential for industrial use. A mature sago palm could yield 50 to 70 kilos of starch. The pith, bud and shoot can also be eaten; the sap can be processed into sugar, vinegar and wine.
Apart from its use as food, Aklanons find sago as the best source of material for making shingles used as roofing material for light houses or huts. Ibisate said that many shingle makers in the province prefer using sago leaves over nipa leaves because sago leaves are more -durable, especially when used in coastal areas. Sago shingles fetch a higher price than nipa shingles. The biggest market for sago shingles is Boracay Island in Malay, Aklan.
Ibisate revealed that there is now a growing demand for sago palm as ornamental plant, both for use indoor and outdoor. Sago, he said, can be grown in an ordinary garden soil and does not require much attention.
Ibisate’s ongoing study on the conservation of sago palm is one of the projects being supported by ASU. At present, he is studying various parameters to further enhance the development of sago by using seeds as planting material.
Meanwhile, Ibisate continues to mass propagate sago palm from seeds to help increase the local supply of seedlings. And the good news is that several hundreds of seedlings are now available to interested growers at P50 each.
Answer
Mike, cannas and day lilies are propagated identically from seed. Actually, regardless of what plant you are propagating by seed, the process is the same for seed starting.
Starting seeds is actually an easy process, but success only comes through many years of trial and error. I have been starting seeds indoors for the last ten years and thoroughly enjoy it. Since I start over 500 seedlings, including annuals, vegetables, and herbs, it does become a full-time hobby. The obvious advantages are the cost savings and the variety as opposed to purchasing seedlings at the garden center.
Most vegetable and annual flower seeds need to be started 6-8 weeks prior to your last expected frost. The exact timing can be found on the seed packets, but 6 weeks is usually a good rule of thumb. Trees and bushes need at least 6 months of growing in a pot before transplanting outdoors.
Never sow seeds deeper than twice their diameter. For small seeds, place them on the surface of the growing medium, and then lightly sprinkle the mix over the seed until it is barely covered. Water from the bottom to avoid disturbing the seed.
Larger seeds may need a little help to germinate, such as seeds with extremely hard shells that need broken down before sowing. These require soaking for 24 hours to break down the coating and improve germination. Another method is stratification; a process that entails nicking the seed with a sharp tool or rubbing the seed lightly on fine grit sandpaper.
Seedlings need to be in simulated sunshine for at least 14 hours per day. They also need 8 hours of dormancy for good growth. You either need to invest in fluorescent bulbs called gro-lights, which are as close to natural light as anything sold on the market, or substitute these with less expensive bulbs. By using one cool and one warm white fluorescent in combination, you will achieve the same effect.
If given the correct conditions, namely adequate moisture, strong light, and healthy soil, the plants will germinate and grow to maturity with few or any problems. To maintain moisture, seeds should be covered with plastic. I grow my seedlings in seed trays with individual cell packs. After sowing, I cover with a pre-fitted plastic dome. But once the first seedlings sprout, it is important to remove the cover to avoid damping-off disease. This is a fatal fungus disease which only attacks young seedlings, and is caused by inadequate air circulation and non-sterile soil. That is why I advise all those who start seeds indoors to only use sterile, soils mixes composed of vermiculite, perlite, and sphagnum moss. These mixes can be purchased at any reputable garden center.
Once the seedlings develop their second set of leaves, you can begin supplementing the plants with a diluted solution of fertilizer. Since you want to keep the nitrogen and salt levels low at this stage of growth, I highly recommend staying away from the chemical mixes. Rather, use a seaweed/fish emulsion formula at ¼ the recommended level. This will help the plants’ development and also help ward off disease. You can purchase these organic formulas at most garden centers or through online websites such as Gardens Alive.
Finally, be sure to keep your fluorescent lights no higher than 3” above the seedlings at all times. This is critical to prevent the plants from becoming weak and spindly. As I mentioned earlier, they should be left on 14 hours per day. If fluorescent lighting is not possible, put them in a southwest window and turn them every three days to avoid leaning.
I am attaching a few websites that should prove helpful. I would also advise you to purchase “The New Seed-Starters Handbook” by Nancy Bubel. It has many good ideas and techniques that benefit even experienced gardeners.
Copied from MIKE
Thursday, 16 April 2009
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