smokebeare
05-10-2006, 02:36 PM
Temperature Temperature may play a role in determining cannabinoid content, but perhaps only through its association with moisture availability. Boucher et al. (1974) reported an increase in cannabinoid content with temperature (32o C. vs. 22o C.), however, some variables such as increased water loss due to accelerated evaporation and plant transpiration at high temperatures were left unaccounted. In contrast, Bazzaz et al. (1975), using 4 Cannabis ecotypes of both tropical and temperate character, demonstrated a definite decrease in cannabinoid production with increased temperature (32o C. vs. 23o C.). Later studies by Braut-Boucher (1980) on clones of 2 strains from South Africa revealed a more complex pattern of biosynthesis according to strain, gender and chemical homologue produced. Clearly, further study of this parameter is needed.
Cannabinoids and environmental stress
Desiccation
THC is a viscous hydrophobic oil (Garrett and Hunt 1974) that resists crystallization (Gaoni and Mechoulam 1971) and is of low volatility (Adams et al. 1941). Since the sticky resins produced and exuded on the surface of the plant are varying combinations of THC, other cannabinoids and a variety of terpenes, they can be seen as analogous to the waxy coatings of the cacti and other succulents that serve as a barrier to water loss in dry environments.
Bouquet (1950) has mentioned that the western side of Lebanon's mountainous Cannabis growing areas is less favorable for resin production because of humid sea winds. De Faubert Maunder (1976) also observed that the copious separable resin needed for hashish production occurs only "in a belt passing from Morocco eastwards, taking in the Mediterranean area, Arabia, the Indian sub-continent and ending in Indo-China." These are mostly areas notable for their sparse rainfall, low humidity and sunny climate. Is it merely coincidence that resin is produced according to this pattern, as well?
Experimental evidence is accumulating that reinforces these notions. Sharma (1975) reported a greater glandular trichome density on leaves of Cannabis growing in xeric circumstances. Paris et al. (1975a) have demonstrated a marked increase in the cannabinoid content of Cannabis pollen with decreased humidity. Murari et al. (1983) grew a range of Cannabis fiber cultivars in three climatic zones of Italy and found higher THC levels in those plants grown in the drier "continental" (versus "maritime") climate. Hakim et al. (1986) report that CBD-rich English Cannabis devoid of THC produced significant amounts of THC and less CBD, when grown in the Sudan. This trend was accentuated in their next generation of plants.
Haney and Kutscheid (1973) have shown significant correlations of plant cannabinoid content with factors affecting soil moisture availability: content of clay or sand, percent slope of plot, and competition from surrounding vegetation. In some cases, this last factor was noted to have induced a stunted plant with "disproportionally smaller roots", which would tend to increase both the frequency and severity of desiccation stress.
In a study of 10 Kansas locations, Latta and Eaton (1975) found wide differences in plant cannabinoid content, observing that "delta-9-THC ranged from 0.012 to 0.49% and generally increased as locations became less favorable for plant growth, suggesting increased plant stress enhanced delta-9-THC production." Mention was also made of a positive correlation between competing vegetation and THC content. Although the sampling area was not considered very moisture deficient, they speculated that "Greater difference among locations might have been observed under drought conditions
Cannabinoids and environmental stress
Desiccation
THC is a viscous hydrophobic oil (Garrett and Hunt 1974) that resists crystallization (Gaoni and Mechoulam 1971) and is of low volatility (Adams et al. 1941). Since the sticky resins produced and exuded on the surface of the plant are varying combinations of THC, other cannabinoids and a variety of terpenes, they can be seen as analogous to the waxy coatings of the cacti and other succulents that serve as a barrier to water loss in dry environments.
Bouquet (1950) has mentioned that the western side of Lebanon's mountainous Cannabis growing areas is less favorable for resin production because of humid sea winds. De Faubert Maunder (1976) also observed that the copious separable resin needed for hashish production occurs only "in a belt passing from Morocco eastwards, taking in the Mediterranean area, Arabia, the Indian sub-continent and ending in Indo-China." These are mostly areas notable for their sparse rainfall, low humidity and sunny climate. Is it merely coincidence that resin is produced according to this pattern, as well?
Experimental evidence is accumulating that reinforces these notions. Sharma (1975) reported a greater glandular trichome density on leaves of Cannabis growing in xeric circumstances. Paris et al. (1975a) have demonstrated a marked increase in the cannabinoid content of Cannabis pollen with decreased humidity. Murari et al. (1983) grew a range of Cannabis fiber cultivars in three climatic zones of Italy and found higher THC levels in those plants grown in the drier "continental" (versus "maritime") climate. Hakim et al. (1986) report that CBD-rich English Cannabis devoid of THC produced significant amounts of THC and less CBD, when grown in the Sudan. This trend was accentuated in their next generation of plants.
Haney and Kutscheid (1973) have shown significant correlations of plant cannabinoid content with factors affecting soil moisture availability: content of clay or sand, percent slope of plot, and competition from surrounding vegetation. In some cases, this last factor was noted to have induced a stunted plant with "disproportionally smaller roots", which would tend to increase both the frequency and severity of desiccation stress.
In a study of 10 Kansas locations, Latta and Eaton (1975) found wide differences in plant cannabinoid content, observing that "delta-9-THC ranged from 0.012 to 0.49% and generally increased as locations became less favorable for plant growth, suggesting increased plant stress enhanced delta-9-THC production." Mention was also made of a positive correlation between competing vegetation and THC content. Although the sampling area was not considered very moisture deficient, they speculated that "Greater difference among locations might have been observed under drought conditions