The cotton area in Karaikal region is 134 ha. Rice-fallow cotton cultivation is a unique system of cultivation, wherein the cotton seeds are dibbled amidst the rice stubbles without tilling the soil to effectively utilize the residual soil moisture. Thus, in this system, cotton faces a severe competition from the early emerging weeds and weeds that are already present in rice field at the time of harvest. The problem of weed menace in rice-fallow cotton would be aggravated if the previous rice crop was not weeded adequately.Weed management during the early stages of cotton growth is more important. Hence, it is necessary to find out the critical period of crop weed competition to make weed control method more effective and economical. At 20 DAS, no weed dry matter production was recorded in weed free for specific period treatments whereas all weedy for specific period treatments recorded significantly higher and similar weed dry matter production . The highest dry weight of weeds was recorded in weedy up to harvest at all the stages followed by weedy up to 100 DAS except at 80 DAS, wherein weedy for 100DAS recorded the highest DMP. In weedy for specific period treatments, the total weed dry matter production increased up to 80 DAS and then decreased slightly. The weed dry weight increased with increase in the duration of weed infestation period and decreased with increase in the duration of weed free period.
The highest dry weight of weeds was observed in weedy up to harvest, throughout the crop growth period .This may be attributed to the highest population of the weeds observed in this treatment which could have effectively used the resources like water, nutrients and sunlight to produce higher dry mater. The weed dry weight was proportional to the density of weeds.This is evident from the significant positive correlation observed between the weed density and dry weight.From 40 DAS onwards ,marijuana grow system weed free up to 20 DAS recorded significantly higher weed dry weight than weedy for 20 DAS and was on par with weedy up to harvest indirecting that a weed free period of initial 20 DAS is insufficient to contain the weed growth. Maintaining the field weed free for first 40, 60, 80 and 100 days reduced the weed dry weight by 50, 72,96 and 97 percent, respectively. This indicates that the dry matter production by weeds can be reduced to half by maintaining the field weed free initial 40 days. Similar results were earlier reported by. Weed interference for only first 20 days caused no significant loss in seed cotton yield . When weeds were allowed to remain beyond 20 days or longer, the yield was reduced significantly. The LSD for seed cotton yield was 3.52 q or 13% of weed free check. By using this LSD = 13% we can see that the seed cotton yield was statistically at par with weed free check when weedy period last only up to initial 20 days and weed free period onward up to 60 days or more weed competition worked out to be between 20 and 60 DAS in rice fallow cotton and also used LSD to find out the critical period of weed competition observed that the critical period of rainfed cotton was 30 to 60 DAS. observed that the critical period for weed competition in irrigated cotton to be from 40 to 60 DAS.
However, maintaining the field weed free beyond80 DAS considerably reduced the seed cotton yield due to lower boll setting percentage. Season-long weed competition the seed cotton yield by 96.5 percent. The yield was found to decline at the rate of 6.019 kg·ha−1 for every kg of weed dry matter produced. The presence of weeds for the first 40 days caused 50.9% reduction in yield indicating that initial weed infestation was harmful to the crop. In contrast, crop initially weeds free for 40days recorded only 14.0% reduction probably because weeds emerged after days did not pose any adverse effects on crop yield. As the opioid epidemic continues, different approaches to pain management are required so as to reduce the amounts of opioid prescribed to patients suffering from chronic pain. One therapeutic option that has been considered is cannabis and multiple states today have instituted a medical marijuana program for different conditions, one of those being chronic pain. Marijuana exerts its effects through the endo-cannabinoid system which has 2 types of receptors: type 1 and 2cannabinoid receptors. CB1 mediates the neuropsychiatric effects of marijuana as the receptor is expressed in the central nervous system.CB2 is expressed in peripheral blood mononuclear cells.Multiple studies have demonstrated an association between marijuana legalization with reductions in rates of opioid overdose and opioid-related hospitalizations among other outcomes. In July 2014, the Compassionate Care Act was enacted in the state of New York allowing the establishment of a medical marijuana program to meet the needs of residents of the state.