Foliar sprays of aqueous 10-50% methanol increased growth and development of C3 crop plants in arid environments. The effects of low levels (<1 ml per plant) of methanol were observed for weeks after the brief time necessary for its rapid metabolism. Within several hours, foliar treatment with methanol resulted in increased turgidity. Plants treated with nutrient-supplemented methanol showed up to 100% increases in yields when maintained under direct sunlight in desert agriculture. In the shade and when winter crops were treated with methanol, plants showed no improvement of growth. When repeatedly treated with nutrient-supplemented methanol, shaded plants showed symptoms of toxicity. Repeated methanol treatments with glycine caused increased turgidity and stimulated plant growth without injury under indirect sunlight, but indoors with artificial illumination, foliar damage developed after 48 hr. Addition of glycerophosphate to glycine/methanol solutions allowed treatment of artificially illuminated plants indoors without injury. Plants with C4 metabolism showed no increase in productivity by methanol treatment. Plants given many applications ofaqueous methanol showed symptoms of nutrient deficiency. Supplementation with a source of nitrogen sustained growth, eliminating symptoms of deficiency. Adjustment of carbon/nitrogen ratios was undertaken in the field by decreasing the source of nitrogen in the final application, resulting in early maturation; concomitantly, irrigation requirements were reduced.Study of the path of carbon in photosynthesis (1- concluded that methanol was utilized for sugar and amino acid production fully as rapidly as was carbon dioxide (4). Since both types of early experiments were performed with substrate on a tracer scale, it was not clear that the rates were comparable or what the pathway for methanol conversion to sucrose involved. Subsequent interest in the subject (5) revealed that plants do indeed metabolize methanol rapidly. The conclusion that methanol is readily oxidized to formaldehyde and converted to fructose 6-phosphate has been supported by investigations with bacteria (6) and fungi (7). It was concluded that formaldehyde condensed with pentose 5-phosphate to yield allulose 6-phosphate, which epimerizes to fructose 6-phosphate.[14C]Formaldehyde was also metabolized by algae but, at the tracer level, little sucrose was produced; the activity was extensively bound to protein and not further utilized. It is possible, then, that the first conversion product of methanol, formaldehyde, also binds to proteins at the sites of its production. More recent studies (8, 9) revealed reactions of other metabolic aldehydes with proteins and their consequent structural alteration.Treatment of agricultural crops in high solar light intensities and other plants was initiated to determine the economic feasibility of methanol application as a source of fixed carbon or of supplemental methyl groups for pectin production. Rather than merely supporting normal growth, treatment with metha...

A strain Botryococcus braunii Kütz. that produces high levels of branched hydrocarbons (botryococcenes) was grown under different environmental conditions to investigate the relationship between growth and hydrocarbon production. Carbon dioxide concentration had the most significant influence on growth; 0.3% CO2‐enriched cultures demonstrated a minimum mass doubling time of ca. 40 h, compared to ca. 6 days for ambient air cultures grown on the same buffered growth medium. The botryococcene fraction, which consisted of 10 identified compounds (CnH2n‐10; n = 30–34), usually constituted ca. 25–40% of the culture dry weight under various growth regimes, including nitrogen‐ and/or phosphate‐deficiencies. CO2 enrichment initially favored the production of the lower botryococcenes (C30–C32), whereas relatively slow‐growing ambient air cultures accumulated C33 and C34 compounds. Colony color changed in response to different light intensities. High light increased the carotenoid/chlorophyll ratio, which resulted in orange colonies. Cultures exposed to low light intensity appeared green. This change in coloration was reversible over a period of a few days, and at no time were the linear hydrocarbons characteristic of the other form of the alga detected. Ostensible colony color is not, therefore, a reliable indicator of qualitative hydrocarbon content. Sequential solvent extraction experiments indicated that up to ca. 7% of the botryococcene fraction was intracellular and that the remainder was located within the colonial matrix. The internal (cellular) pool principally consisted of C30–C32 botryococcenes, whereas the external (colonial matrix) pool contained >99% of the C33 and C34 compounds, in addition to large amounts of the lower botryococcenes. These results, taken in conjunction with other data, are compatible with the hypothesis that the C30 botryococcene is the precursor, presumably via methylation, of the higher botryococcenes.

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