Leaf morphology
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Leaf morphology in Cannabis is the form of the foliage leaf: the number, shape, size and margins of its leaflets and the arrangement of leaves on the stem. The foliage leaf of Cannabis sativa is palmately compound, its serrated leaflets spreading from the tip of a long petiole.[1]
Leaf form changes from node to node as the plant grows, from single-leafleted seedling leaves to many-leafleted adult leaves and back to small leaves in the inflorescence.[2] Leaflet width differs between lineages and has long been used to tell kinds of Cannabis apart by eye. Narrow and broad leaflets are part of what the trade calls "sativa" and "indica", a division that genetic data do not support.[2] Plant-variety offices and gene banks score leaf characters on specified leaves of the plant, following standard descriptor lists. Forms that depart from the usual leaf, with webbed or few leaflets, leaflets cut into secondary lobes, or more than two leaves at a node, have been reported from cultivation, inbred lines and mutagenesis experiments.
The leaf and its leaflets
The leaf of Cannabis is palmately compound. Leaves are opposite low on the stem and alternate above. Leaves on the lower stem have 5 to 11 leaflets and those near the top one to three.[1] The petiole is 2 to 7 cm long and the stipules are linear.[3][4]
The leaflets are usually lanceolate to linear, with acuminate tips and coarsely serrate margins. The middle leaflet is the longest. Leaflets are mostly 7 to 15 cm long and 0.5 to 1.5 cm wide, with extremes of 3 cm in length and 0.2 to 2 cm in width.[3] The two surfaces of the blade differ. The upper surface is dark green and rough with stiff, bulbous-based hairs that sit on cystoliths, hard bodies of calcium carbonate. The lower surface is whitish green and covered with appressed hairs, with scattered yellowish-brown resinous dots and sessile glands.[5][3][4][6]
The hop genus Humulus, also in the family Cannabaceae, has opposite leaves that are more or less cordate and divided into three to seven lobes when well developed; its uppermost leaves are sometimes simple.[7]
Changes along the plant
The leaves of a Cannabis plant change along the main stem in a marked heteroblastic, or juvenile-to-adult, progression.[2] The test guidelines of the International Union for the Protection of New Varieties of Plants (UPOV) use these changes to mark the plant's growth stages. One, three and five leaflets on the first three leaf pairs mark early vegetative growth. The change from opposite to alternate leaves on the main stem marks the induction of flowering.[8]
In the seedling the first true leaves above the cotyledons each have a single serrated leaflet. The second leaves usually have three leaflets, and five is the most frequent number at the third node.[2][9] Through vegetative growth leaflet number rises to a maximum of 9 to 13 in young adult leaves at the growing tip, and the leaves are opposite on the lower stem.[2][10] Once the plant turns to flowering the leaves become alternate,[8] and leaflet number falls again up to the top of the inflorescence.[2] The small leaves with few leaflets that grow among the flower clusters are known as "sugar leaves", and the larger palmately compound leaves below them as "fan leaves".[11]
In plants of the cultivar White Widow grown under controlled conditions, nodes 1 to 11 were opposite and the alternate arrangement began at node 12. The plants were moved from long days to short days after the twelfth node.[9] The leaves had nine leaflets each from node 6 to node 13; leaflet number later fell to five at nodes 20 to 22 and three at nodes 23 and 24, and the leaf at node 25 had a single leaflet.[9] In the same plants the terminal leaflet's length-to-width ratio dropped slightly from 1.96 at the first node to 1.8 at the third, then rose to 5.5 at node 15. The serrations on that leaflet numbered 22 at the first node and about 17 at the second, rose to about 36 at node 14 and fell to six at node 25.[9]
In a study of 341 leaves from nine accessions, leaflet shape changed markedly between three- and five-leafleted leaves, where the leaflets became narrower and more acuminate; between leaves with more leaflets the change was more gradual. The series did not run the same way in every accession.[2] Up the main stem the leaves also become smaller, with shorter petioles.[12]
One plant can carry leaves of all three kinds used to label plants in the trade: narrow-leafleted "sativa", broad-leafleted "indica" and three-leafleted "ruderalis" leaves. Carlson and colleagues, who saw this on single genotypes in hemp breeding families, attributed it to ontogenetic heterophylly. In their plants mean leaflet number rose with the day on which flowering ended, from 3.9 in plants that finished before 50 days after planting to 6.3 in those that finished after 70 days.[13]
Leaflet shape between lineages
In the 1980s drug plants came to be divided under the labels "Indica" and "Sativa". "Indica" was applied to plants with broad leaflets, a short and compact habit and early maturity, with evidence of landrace ancestors in Central Asia, chiefly Afghanistan. "Sativa" was applied to plants with narrow leaflets, a tall and diffuse habit and late maturity, with evidence of landrace ancestors in South Asia, chiefly India.[11] In the trade, taller plants with narrow leaflets and a high THC content are called "sativa", and shorter, bushier plants with wider leaflets and high percentages of both CBD and THC are called "indica". The classification is not supported by genetic data.[2] Leaf traits are routinely used to label plants C. sativa, C. indica, C. ruderalis or hybrids, a practice Carlson and colleagues call "weakly justified".[13]
In the taxonomic treatment of McPartland and Small (2020), leaf characters are among those that separate the domesticated drug varieties of C. sativa subsp. indica. They are scored on fan leaves near the base of the inflorescence. In var. indica these leaves are lighter green and usually have seven leaflets with gaps between their margins; the central leaflet is long and narrow, lanceolate or linear-lanceolate, with a length-to-width ratio of 6 or more. In var. afghanica they are darker green and usually have nine leaflets whose margins overlap; the central leaflet is long and broad, often oblanceolate, with a ratio below 6.[11] For the dark green leaves of var. afghanica they cite Vavilov's name "black hemp".[11]
In geometric models of leaflet shape across nine accessions, the most pronounced change, both between accessions and along the plant, was from narrow to wide leaflets, the stereotypical "sativa" and "indica" forms. The width-to-length ratio of the central leaflet on its own did not separate the accessions well.[2] In de Meijer's trials of a germplasm collection, leaflet width was the single character that best separated chemical phenotypes, but the phenotypes still overlapped considerably and no clear-cut discrimination was possible.[14] He added that the result may be biased, since the 1990 trial held indica-type drug strains only and no sativa drug strains, which combine high THC with the form of non-drug sativas; one such strain in the 1993 trial had very slender leaflets.[14] In 297 plants of a backcross between a narrow-leafleted "Carmagnola" hemp and a broad-leafleted "Afghan Kush", leaf shape was unrelated to sex, to cannabinoid production and to other measured traits, which suggested to the authors that these traits segregate independently.[15] A strong correlation between central-leaflet proportions and cannabinoid content, reported from clones of 21 cultivars, was not confirmed by two later studies.[2][16]
In field measurements of 35 wild populations from the Potohar Plateau and the Lesser Himalayas of Pakistan, the central leaflet was 8.1 to 15.1 cm long and 0.9 to 2 cm wide, and the number of primary serrations ranged from 24 to 47. Altitude was positively correlated with central-leaflet width, petiole length and leaf area, while central-leaflet length and the number of serrations did not change with altitude.[17] When 21 Chinese accessions, nine wild and 12 cultivated (10 of them landraces), were grown together at Kunming, the wild plants had significantly narrower leaflets and compound leaves and shorter petioles than the cultivated ones.[18]
Small, Jui and Lefkovitch (1976) wrote that the smaller leaflets of intoxicant plants, among the most obvious features that set those plants apart, are subject to great environmental modification like many morphological characters of Cannabis.[10]
Recording leaf characters
Descriptor lists for Cannabis name the leaf to be measured and the characters to score on it. The UPOV guidelines for testing hemp varieties for distinctness, uniformity and stability score leaf variegation as absent or present, the number of leaflets in five states from three or fewer to 11 or more, and the length and width of the central leaflet. The leaflet count is the predominant number in the centre of the plant. For cross-pollinated, seed-grown varieties the leaves observed are the last pair of opposite, fully expanded leaves.[8] The United States Department of Agriculture hemp handbook takes leaf data from the uppermost set of mature leaves just before flowering begins, as the mean of five leaves from each of ten plants. Its leaf fields are petiole length and the length and width of the central leaflet in centimetres, measured with the leaf and petiole flattened, and the presence of variegation.[19]
Small, Jui and Lefkovitch (1976) scored nine characters on the middle leaflet of a mid-stem leaf: leaflet number, length, width and thickness, petiole length, the length of the leaflet's unserrated tip, the number of serrations on one side, how strongly the serrations curve forward, and where along the leaflet it is widest.[10] De Meijer scored leaflet width in nine classes, from very narrow to overlapping margins, and a leaflet index, the length-to-width ratio of the central leaflet of the primary leaf at the fourth stem node, averaged over five plants.[14] McPartland and Small classed a central leaflet as lanceolate when its widest point lies in the half nearest the base and as oblanceolate when it lies beyond the midpoint, measuring the distance from the base to the widest point as a fraction of the leaflet's length.[11]
Leaf-shape mutants
Leaf forms that depart from the usual series have been described in four directions: leaflets fused into a webbed blade, fewer leaflets, leaflets divided into secondary lobes, and more than two leaves at a node. Some were found in cultivation and some appeared in inbred lines or after chemical mutagenesis. Leaves with a single leaflet are part of the normal series at the base and the top of the plant.[2]
Webbed and fused leaflets
A review of ornamental uses of Cannabis by Hesami and colleagues (2022) states that "Ducksfoot" strains derive from a spontaneous mutation and are valued as potted plants for their webbed leaves and purple inflorescences. The same review describes Australian Bastard Cannabis, a shrub-like plant with small, smooth, non-serrated leaves, as another potential mutant for the potted-plant trade.[20]
Three-leafleted leaves
In the TILLCANN mutant population, made by ethyl methanesulfonate mutagenesis of seed from a line bred from a CBD-producing plant and the hemp cultivar Finola, plants carrying a mutation in the gene CsTCP4 had three-leafleted, hairless leaves with reduced serration and venation. In one backcross family 13 of 25 plants showed the trait; the other 12 had the palmate, rugose, regularly serrated leaves of the wild type. The authors call the mechanism unclear and take the link between the mutation and the altered leaflet number and form to suggest a role for the gene in leaf development in Cannabis.[21]
Leaflets divided into secondary lobes
Serkov and Klimova (2016), summarising earlier Soviet research on inbred hemp, state that plants with pinnately incised (перистонадрезанные) leaves, like those with whorled leaves and with branched or fasciated stems, split out in inbred lines and are due to single recessive genes. These recessive forms are rare in freely cross-pollinating populations and become much more frequent in inbred lines. Selfed lines also differed widely in the size, shape, colour and number of lobes of their leaves.[22] In Mishchenko's selfing experiments with Ukrainian hemp cultivars, deformed leaves appeared only in the first inbred generation of the cultivar Zolotonoshski 15. Mishchenko could not say whether the anomalies seen in his inbred progenies were mutations, morphoses or phenocopies.[23]
A United States patent granted in 2022 for a Cannabis plant named 'FS-tp2' defines a "Type 2" leaf: a palmate leaf of typically five to nine leaflets, each bearing many, usually about 9 to 30 or more, "bipinnate lobes or secondary leaflets". The patent calls this, in colloquial terms, "an atypical, fern-like morphology".[24] In its description the venation is unaltered and the secondary leaflets lie along both sides of each vein, increasing in number as the plant ages; from an ordinary leaf to the most divided ones, the deep serrations deepen into hooked serrations, then into lobes and finally into secondary leaflets. The first true leaves usually have three or five leaflets instead of one.[24] The patent traces the plant to a 2017 cross between the cultivars 'Pineapple Express' and 'Holy Banana' in eastern Madera County, California. Two of the 20 F1 plants, both male, showed the form; 30 of 300 F2 seedlings and all nine F3 plants screened carried it.[24]
In 1869 the teratologist Maxwell Masters wrote that laciniate varieties of plants, with leaves cut into narrow segments, "are of frequent occurrence in gardens where they are often cultivated for their beauty or singularity".[25]
Whorled leaves
In whorled plants three or more leaves arise at each node in place of the usual opposite pair or single alternate leaf. Hesami and colleagues (2022) state that Cannabis genotypes with whorled phyllotaxy have resulted from spontaneous somatic mutations.[20] In the Soviet inbreeding work summarised by Serkov and Klimova, whorled leaves were among the forms ascribed to single recessive genes.[22] Mishchenko cites Migal's observation that in selfed hemp the leaves often lose their symmetrical arrangement on the stem.[23] Seedlings in the TILLCANN mutant population showed altered phyllotaxis and cotyledon number.[21]
Variegated and pale leaves
Both the UPOV guidelines and the USDA handbook score variegation.[8][19] Hesami and colleagues (2022) describe the cultivar Divina as a mutant with albinism that produces variegated leaves, and call it "the only selected mutant introduced as an ornamental cannabis plant". They also cite radiation mutagenesis that produced two low-THC cultivars with yellow distal leaflets and red petioles.[20] In 1938 Y. Imai described two colour mutants of hemp induced by X-raying pollen, one of them a yellow mottling of young leaves that later turn green.[26]
Genetic control of leaf division
In model plants, leaves are either simple, with one continuous blade, or compound, with the blade split into separate leaflets. Class I KNOX homeobox genes are usually not expressed in simple leaves but are expressed in the leaves of many plants with compound leaves, where they are a major driver of leaf complexity. The level of the gene CUC2 is an important determinant of how far the leaf margin grows out. In Arabidopsis thaliana, which has simple leaves, lowering the CIN-TCP genes, TCP4 among them, gives deeper marginal serrations, and lowering both the CIN-TCP and the class II KNOX genes gives a highly branched blade with distinct leaflet-like outgrowths.[27][28] In Cardamine hirsuta the gene REDUCED COMPLEXITY is needed for leaflets to form, and loss-of-function mutants have lobed leaves.[27][29]
A tomato heirloom from Russia, 'Silvery Fir Tree', has a highly complex leaf with narrower leaflets than processing tomatoes. It carries a single-nucleotide deletion in the homeobox of the gene BIPINNATA, which truncates the BIP protein and raises the expression of class I KNOX genes in the leaf. The extreme complexity of the leaf that results probably led to the plant's use as an ornamental.[29][30] In Cannabis the CsTCP4 mutant had fewer leaflets with less serration, while lowering CIN-TCP genes in Arabidopsis deepens serration.[21][27]
Distortion by pests, pathogens and herbicides
Several pests, pathogens and herbicides deform the leaves of Cannabis. The hemp russet mite (Aculops cannabicola) first curls the leaf edges, which are later russeted.[31][32] Mite and aphid feeding can make leaves cup, yellow and drop.[33]
Among viruses, beet curly top virus has been confirmed in cannabis plants whose uppermost leaves were curled, twisted and deformed, in some plants so severely that the whole plant looked malformed.[34] Most plants infected with hop latent viroid show no symptoms; in susceptible cannabis the reported symptoms include smaller leaves, stunting and malformation.[35]
In trials simulating drift of the growth-regulator herbicides 2,4-D and dicamba onto hemp, the symptoms included epinasty, leaf cupping and strongly malformed terminal growth. In one trial a tenth of the field rate of dicamba cupped the terminal leaflets and crinkled the secondary leaves.[36] In a greenhouse screen clopyralid elongated the stems and rolled the leaves of hemp.[37]
See also
References
- ↑ 1.0 1.1 Wu, Zhengyi; Zhou, Zhe-Kun; Bartholomew, Bruce. "Cannabis". Flora of China, Vol. 5. p. 75. Retrieved 11 October 2026 – via eFloras.org.
- ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 Balant, M.; Garnatje, T.; Vitales, D.; Hidalgo, O.; Chitwood, D.H. (2024). "Intra-leaf modeling of Cannabis leaflet shape produces leaf models that predict genetic and developmental identities". New Phytologist. 243 (2): 781–796. doi:10.1111/nph.19817.
- ↑ 3.0 3.1 3.2 Wu, Zhengyi; Zhou, Zhe-Kun; Bartholomew, Bruce. "Cannabis sativa". Flora of China, Vol. 5. p. 75. Retrieved 11 October 2026 – via eFloras.org.
- ↑ 4.0 4.1 Small, Ernest. "Cannabis sativa". Flora of North America, Vol. 3. Retrieved 11 October 2026 – via eFloras.org.
- ↑ Wu, Zhengyi; Zhou, Zhe-Kun; Bartholomew, Bruce. "Cannabaceae". Flora of China, Vol. 5. p. 74. Retrieved 11 October 2026 – via eFloras.org.
- ↑ Qaiser, M. "Cannabis sativa". Flora of Pakistan. Retrieved 11 October 2026 – via eFloras.org.
- ↑ Wu, Zhengyi; Zhou, Zhe-Kun; Bartholomew, Bruce. "Humulus". Flora of China, Vol. 5. p. 74. Retrieved 11 October 2026 – via eFloras.org.
- ↑ 8.0 8.1 8.2 8.3 International Union for the Protection of New Varieties of Plants (26 August 2025). Hemp, Cannabis (Cannabis sativa L.): Guidelines for the Conduct of Tests for Distinctness, Uniformity and Stability (Report). Geneva: UPOV. TG/276/2.
- ↑ 9.0 9.1 9.2 9.3 Hesami, M.; Pepe, M.; Jones, A.M.P. (2023). "Morphological characterization of Cannabis sativa L. throughout its complete life cycle". Plants. 12 (20) 3646. doi:10.3390/plants12203646.
- ↑ 10.0 10.1 10.2 Small, E.; Jui, P.Y.; Lefkovitch, L.P. (1976). "A numerical taxonomic analysis of Cannabis with special reference to species delimitation". Systematic Botany. 1 (1): 67–84. doi:10.2307/2418840.
- ↑ 11.0 11.1 11.2 11.3 11.4 McPartland, J.M.; Small, E. (2020). "A classification of endangered high-THC cannabis (Cannabis sativa subsp. indica) domesticates and their wild relatives". PhytoKeys. 144: 81–112. doi:10.3897/phytokeys.144.46700.
- ↑ Spitzer-Rimon, B.; Duchin, S.; Bernstein, N.; Kamenetsky, R. (2019). "Architecture and florogenesis in female Cannabis sativa plants". Frontiers in Plant Science. 10 350. doi:10.3389/fpls.2019.00350.
- ↑ 13.0 13.1 Carlson, C.H.; Stack, G.M.; Jiang, Y.; Taşkıran, B.; Cala, A.R.; et al. (2021). "Morphometric relationships and their contribution to biomass and cannabinoid yield in hybrids of hemp (Cannabis sativa)". Journal of Experimental Botany. 72 (22): 7694–7709. doi:10.1093/jxb/erab346.
- ↑ 14.0 14.1 14.2 de Meijer, E. (1994). Diversity in Cannabis (PhD thesis). Wageningen: Landbouwuniversiteit Wageningen. doi:10.18174/207065. ISBN 90-5485-338-7.
- ↑ Vergara, D.; Feathers, C.; Huscher, E.L.; Holmes, B.; Haas, J.A.; Kane, N.C. (2021). "Widely assumed phenotypic associations in Cannabis sativa lack a shared genetic basis". PeerJ. 9 e10672. doi:10.7717/peerj.10672.
- ↑ Murovec, J.; Eržen, J.J.; Flajšman, M.; Vodnik, D. (2022). "Analysis of morphological traits, cannabinoid profiles, THCAS gene sequences, and photosynthesis in wide and narrow leaflet high-cannabidiol breeding populations of medical cannabis". Frontiers in Plant Science. 13 786161. doi:10.3389/fpls.2022.786161.
- ↑ Younas, M.; Qureshi, R.; van Velzen, R.; Mashwani, Z.R.; Saqib, Z.; et al. (2024). "Geo-climatic factors co-drive the phenotypic diversity of wild hemp (Cannabis sativa L.) in the Potohar Plateau and Lesser Himalayas". BMC Plant Biology. 24 (1) 1031. doi:10.1186/s12870-024-05730-0.
- ↑ Chen, Xuan; Guo, Hong-Yan; Zhang, Qing-Ying; Wang, Lu; Guo, Rong; Zhan, Yi-Xun; Lv, Pin; Xu, Yan-Ping; Guo, Meng-Bi; Zhang, Yuan; Zhang, Kun; Liu, Yan-Hu; Yang, Ming (2022). "Whole-genome resequencing of wild and cultivated cannabis reveals the genetic structure and adaptive selection of important traits". BMC Plant Biology. 22 (1) 371. doi:10.1186/s12870-022-03744-0.
- ↑ 19.0 19.1 Stansell, Z.; Barraco, A.; et al., eds. (16 December 2025). USDA Hemp Phenotyping and Protocol Handbook, Version 4 (Report). United States Department of Agriculture.
- ↑ 20.0 20.1 20.2 Hesami, M.; Pepe, M.; Baiton, A.; Salami, S.A.; Jones, A.M.P. (2022). "New insight into ornamental applications of Cannabis: perspectives and challenges". Plants. 11 (18) 2383. doi:10.3390/plants11182383.
- ↑ 21.0 21.1 21.2 Duarte-Delgado, D.; Alexiou, K.G.; Pujol, M.; Uauy, C.; Adamski, N.M.; et al. (2025). "TILLCANN: a TILLING platform in Cannabis sativa for mutation discovery and crop improvement". Molecular Horticulture. 5 (1) 54. doi:10.1186/s43897-025-00176-w.
- ↑ 22.0 22.1 Serkov, V.A.; Klimova, L.V. (2016). "Sozdanie i izuchenie samoopylennykh linii dlya prakticheskoi selektsii nenarkoticheskoi konopli posevnoi" [Creation and study of self-pollinated lines for the practical breeding of non-narcotic seed hemp]. Niva Povolzh'ya (in русский) (2 (39)): 52–60.
- ↑ 23.0 23.1 Міщенко, С.В. (2011). "Зміна ознак рослин конопель у потомстві самозапилених особин сортів середньоросійського і південного типів" [Change of traits of hemp plants in the progeny of self-pollinated individuals of Central-Russian and southern-type cultivars]. Plant Breeding and Seed Production (in українська) (100): 120–130. doi:10.30835/2413-7510.2011.66536.
- ↑ 24.0 24.1 24.2 Johnson, J.R. (17 May 2022). "Cannabis plant named 'FS-tp2'". Google Patents. US 11,330,778 B2. Retrieved 9 October 2026.
- ↑ Masters, M.T. (1869). Vegetable Teratology: An Account of the Principal Deviations from the Usual Construction of Plants. London: Ray Society (Robert Hardwicke) – via Project Gutenberg.
- ↑ Imai, Y. (1938). "Sex-linked mutant characters in the hemp, Cannabis sativa". Journal of Genetics. 35 (3): 431–432. doi:10.1007/bf02982366.
- ↑ 27.0 27.1 27.2 Byrne, M.E.; Imlay, E.; Ridza, N.N.B. (2024). "Shaping leaves through TALE homeodomain transcription factors". Journal of Experimental Botany. 75 (11): 3220–3232. doi:10.1093/jxb/erae118.
- ↑ Nikovics, K.; Blein, T.; Peaucelle, A.; Ishida, T.; Morin, H.; et al. (2006). "The balance between the MIR164A and CUC2 genes controls leaf margin serration in Arabidopsis". The Plant Cell. 18 (11): 2929–2945. doi:10.1105/tpc.106.045617.
- ↑ 29.0 29.1 Nakayama, H.; Leichty, A.R.; Sinha, N.R. (2022). "Molecular mechanisms underlying leaf development, morphological diversification, and beyond". The Plant Cell. 34 (7): 2534–2548. doi:10.1093/plcell/koac118.
- ↑ Nakayama, H.; Ichihashi, Y.; Kimura, S. (2023). "Diversity of tomato leaf form provides novel insights into breeding". Breeding Science. 73 (1): 76–85. doi:10.1270/jsbbs.22061.
- ↑ Petanovic, R.; Magud, B.; Smiljanic, D. (2007). "The hemp russet mite Aculops cannabicola (Farkas, 1960) (Acari: Eriophyoidea) found on Cannabis sativa L. in Serbia: supplement to the description". Archives of Biological Sciences. 59 (1): 81–85. doi:10.2298/abs0701081p.
- ↑ Turillazzi, F.; De Lillo, E.; Mazza, G.; Marraccini, D.; Gagnarli, E.; et al. (2022). "The hemp russet mite Aculops cannabicola (Farkas, 1960) (Acari Eriophyoidea) first detected in Italy on Cannabis sativa L.". Redia. 105: 141–143. doi:10.19263/redia-105.22.18.
- ↑ Pulkoski, M.; Burrack, H. (2024). "Assessing the impact of piercing-sucking pests on greenhouse-grown industrial hemp (Cannabis sativa L.)". Environmental Entomology. 53 (1): 1–10. doi:10.1093/ee/nvad044.
- ↑ Punja, Z.K.; Kahl, D.; Reade, R.; Xiang, Y.; Munz, J.; Nachappa, P. (2023). "Challenges to Cannabis sativa production from pathogens and microbes—the role of molecular diagnostics and bioinformatics". International Journal of Molecular Sciences. 25 (1) 14. doi:10.3390/ijms25010014.
- ↑ Adkar-Purushothama, C.R.; Sano, T.; Perreault, J.-P. (2023). "Hop latent viroid: a hidden threat to the cannabis industry". Viruses. 15 (3) 681. doi:10.3390/v15030681.
- ↑ Essman, A.I.; Loux, M.M.; Lindsey, A.J.; Kelly, M.; Yao, S.; Jordan, C. (2024). "Evaluating the vegetative and reproductive response of hemp (Cannabis sativa) to simulated off-target events of 2,4-D and dicamba". Weed Technology. 38 e54. doi:10.1017/wet.2024.38.
- ↑ Kaur, N.; Kumar, A.; Malik, T.; Girdhar, M.; Singh, M.; et al. (2025). "Herbicide use and weed management strategies in hemp cultivation". Journal of Cannabis Research. 7 (1) 27. doi:10.1186/s42238-025-00280-0.