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detoxify herbicide residues in the soil could be beneficial in conjunction with this approach, but unfortunately this approach treats the symptoms and not the cause. The use of herbicide resistant plant is also contra to the development of insect and pest resistant plants which promote reduced herbicide use. In this sense the use of genetically engineered herbicide resistant plants is not consistent with the development of low input sustainable agriculture (LISA).
Another and complementary approach to increasing crop productivity is the development of non-polluting organic biostimulants (OBs) that increases plant growth and vigor through increased efficiency of nutrient and water uptake. In our research we have developed a new biostimulant that consists of a mix of marine algae, huxnic adds and non-hormonal metabolic enhancers that greatly increases root and top growth of plants while decreasing fertilizer requirement 40-50% in a number of species (coffee, several grass species, pines, Douglas-fir, Alnus, Gliricidia). The biostimulant also increases resistance to stressors such as low soil water potential and possibly residual herbicides in soil (Berlyn and Beck 1980, Berlyn, Anoruo, Russo, Letourneau Unpublished). The biostimulant has antioxidant as well nutrient uptake enhancement function and can promote wood formation even in pine stems growing in the presence of otherwise toxic levels of growth regulators (Berlyn and Beck 1980). Since most plants are more than 60% cell walls, it is quite reasonable that these OBs promote increased rates of plant biomass production. This of course has importance in many food crop agriculture systems as well as in forestry, horticulture, agroforestry, and coffee and turf grass production.
The individual components of the biostimulant have been used to increase plant growth and vigor in the past, but have recently~attracted more attention (Booth 1966, Senn and Kingman 1973, Hernando 1968, Berlyn and Beck 1980, Chinoy 1984, Mettixtg 1985, Oerli 1987).


MATERIALS AND METHODS


Seeds of Pinus caribaea obtained from Mountain Pine Ridge, Belize (Seed Lot No. 85/75) were broadcast in a plastic flat containing acid washed coarse quartz sand (4Q Roc, Pennsylvania Glass and Sand Co., Berkeley Springs, West Virginia) on the 17th of December, 1987. When the seedlings
 

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