Silver Calyx by Calyx Garden is a well-rounded hybrid created from powerful and popular dna. This strain of cannabis is a cross of Grape Calyx plus a rogue seed noticed in a GG#4 bag. The sticky, trichome laden exterior makes Silver Calyx an apt name for this pungent flower. It carries a classic GG#4 scent full of earth and skunk, however also includes a distant, sweet berry undertone. Make use of Silver Calyx to help stave off migraines, minor physical discomfort, and insomnia.
When smoked or converted into an edible form, the flavor of the Silver Calyx strain is best described as Lemon, Tree-fruit, and Pine.
Mean values of statistical analyses comparing variation between cross-fertilized and hermaphroditic populations of C. sativa.
Three strains of marijuana – “Moby Dyck,” “Space Queen,” and “Lemon Nigerian” – were cultivated in a commercial indoor growing facility according to the regulations and guidelines issued by Health Canada under an MMPR – Marihuana for Medical Purposes – license. The plants were initiated from rooted cuttings and provided with the nutrient regime for hydroponic culture as described elsewhere (Punja and Rodriguez, 2018). Lighting, temperature and growth conditions were provided in accordance with industry production standards to ensure pistillate inflorescence development (Small, 2017). The plants were first maintained in the vegetative stage for 2 weeks at a temperature range of 23–26°C with a 24 h photoperiod under a light intensity of 120 μmol m –2 s –1 . They were subsequently transferred into a flowering room for an additional 6–7 weeks to induce pistillate inflorescence development under a modified photoperiod regime that consisted of reduced lighting duration and intensity (10 h photoperiod and 70 μmol m–2 s –1 light intensity) ( Figures 1A,B ).
Assessing Sequence Variation of PCR Bands From Female and Male Plants
The spontaneous development of hermaphroditic inflorescences (pistillate flowers containing anthers) on female plants during commercial marijuana cultivation creates a problem for growers, since the resulting seed formation reduces the quality of the harvested flower (Small, 2017). The allocation of resources by the female plant to pollen production, followed by seed production, can result in disproportionately lower levels of terpenes and essential oils (by up to 56%) in the pollinated flowers compared to unfertilized female flowers (Meier and Mediavilla, 1998). Therefore, inflorescences containing seeds are of lower quality and frequently not suited for sale. Unpollinated female flowers, on the other hand, continue to expand growth of the style-stigma tissues, potentially to increase opportunities for attracting pollen (Small and Naraine, 2015), and consequently are more desirable commercially. In the present study, we observed spontaneous formation of hermaphroditic flowers on 5–10% of plants of three different strains of marijuana grown indoors under commercial conditions. In most cases, small clusters of anthers developed within certain female flowers, replacing the pistil. In rare cases (two out of 1,000 plants), the entire female inflorescence was displaced by large numbers of clusters of anthers instead of pistils ( Figure 3 ). The factors which trigger this change in phenotype have not been extensively researched. This is due, in part, to the restrictions placed by government regulatory agencies on conducting research experiments on flowering cannabis plants (including in Canada), which reduces the opportunity to conduct the types of controlled experiments that are needed to elucidate the basis for hermaphroditism.
Physical or chemical stresses can also have a role in inducing staminate flower development on female plants of marijuana. For example, external environmental stresses, e.g., low photoperiods and reduced temperatures in outdoor production, were reported to increase staminate flower formation (Kaushal, 2012). Some plants formed hermaphroditic flowers when female plants were exposed to extended periods of darkness early during growth or during altered photoperiods during the flowering stage, although the exact conditions were not described (Rosenthal, 1991, 2000). Such stress factors could affect internal phytohormone levels, such as auxin:gibberellin ratios (Tanimoto, 2005), which could in turn trigger hermaphroditic flower formation in marijuana plants. In Arabidopsis plants, auxin, gibberellin and ethylene interact with jasmonic acid (JA) to alter stamen production (Song et al., 2013, 2014). Consequently, jasmonic-acid deficient mutant Arabidopsis plants exhibited male sterility, with arrested stamen development and non-viable pollen (Jewell and Browse, 2016) while JA treatment restored stamen development in these mutants. In marijuana plants, environmental stress factors which enhance JA production could potentially promote hermaphroditic flower formation but this requires further study. Lability of sex expression may offer advantages in promoting seed formation in hermaphroditic plants subject to environmentally stressful conditions (Ainsworth, 2000).
Plant Growth Conditions
Transposable elements (TEs) have been found throughout eukaryotic genomes, including those of yeast, drosophila, rice and humans (Chénais et al., 2012). In C. sativa, Sakamoto et al. (2005) showed the presence of multiple Copia-like retrotransposon locations along the Y chromosome and throughout the autosomes in hemp. In the present study, a GAG pre-integrase domain was found upstream of the rve Superfamily domain in three female marijuana strains. Both domains are features of Class I LTR retrotransposons (Wicker et al., 2007; Llorens et al., 2011). According to NCBI’s Conserved Domain Database, the GAG pre-integrase domain (pfam13976) is associated with retroviral insertion elements. In addition, the placement of these domains is characteristic of the Copia Superfamily of LTR retrotransposons (Wicker et al., 2007). Therefore, the presence of Copia-like retrotransposons within the C. sativa genome is confirmed, but their functions or association with the expression of male or female phenotype remains to be determined.