The path of carbon in photosynthesis: improved crop yields with methanol.

Abstract

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...

Effects of foliar and root applications of methanol or ethanol on the growth of tomato plants (Lycopersicon esculentumMill)

“…Three applications of 10% methanol increased growth rate and yield of tomatoes without any symptoms of phytotoxicity to leaves. Nonomura & Benson's ( 1992) data supported the hypothesis that the increase in growth was because of an inhibition of photosynthate loss as a result of photo-respiration. Ethanol has also been shown to have effects in plant tissues, often associated with ethylene activity (Heins H93086 Received 17 December 1993;accepted 17 June 1994accepted 17 June 1980Saltveit 1989;Wu et al 1990;Mencarelli 1991) and on stomatal resistance by its effect on removing leaf resin (Meinzier et al 1990).…”

“…The methanol growth stimulation data, although not of the same magnitude, agrees with that of Nonomura & Benson (1992). This may have been because no wetting agent or nitrogen supplementation was used in our experiment.…”

Enhanced Formaldehyde Detoxification by Overexpression of Glutathione-Dependent Formaldehyde Dehydrogenase from Arabidopsis

“…It has been reported that foliar application of methanol can stimulate plant growth (Nonomura and Benson, 1992) and that methanol is quickly oxidized in most plant tissues successively to formaldehyde, formic acid, and CO 2 (Cossins, 1964). Formaldehyde can be incorporated to plant C1 metabolism mainly by two metabolic pathways that involve folatemediated and -independent reactions (Hanson and Roje, 2001).…”

Melas Uygulamalarının Şeker Pancarında (Beta vulgaris L.) Kök Verimi ve Şeker Oranı Üzerine Etkilerinin Belirlenmesi

“…Makela et al (1998) stated that the Glycinebetaine, product from sugar beet, is (Mweresa et al 2014). Releasing of CO 2 from fermentation of molasses creates an additional carbon source to the plant (Quan et al 2005) and thus, photorespiration rate of the plants reduced and net photosynthesis increase (Nonomura and Benson 1992).…”