CANNABIS REFERENCES for breeding

I suggest we start making a single location scientific reference bibliography with abstracts and full text or links to the articles or books as well as the info to be able to find it in a library. This can be done for Breeding, Pollen, Sex, Genes, Cannabinoids, Pests, Molecular Biology, Synthases, Non-Plant references, etc. etc. I guess first we need a list of categories to put the different articles and books in, some articles and books will need to be in more then one category. I guess we need for people to send in categories as well as articles or references. We can also make a non-science popular article section for articles and books that would help people. Some of the FAQ's or Stickys may need to be added to the references.
So,
ANY IDEAS FOR CATEGORIES? AS WELL AS SUBCATEGORIES?
ANY IDEAS FOR ARTICLES SCIENTIFIC OR POPULAR?
BOOKS THAT ARE NEEDED OR HELPFUL.
IF YOU SEND IN A REFERENCE TRY AND INCLUDE THE ABSTRACT, FULL REFERENCE INFO TO ASSIST FINDING IN A LIBARY, A LINK TO THE FULL TEXT, FULL TEXT. OR FOR BOOKS A REVIEW AND/OR TABLE OF CONTENTS.
Maybe a category for JUNK INFO?
A rating system 1-10 leafs for usefullness and quality of info.
JLP, SUZI, or I will move and organize the articles into a bibliographic reference that is easy to use for all. And stick them in a new post in the STRAINS & HYBRIDS, OR THE BREEDERS LAB, or where ever they should be. Some articles may be in more then one place, but ALL ARTICLES will be in one MASTER location to make it easier to find by everyone.


Martin, L., D.M. Smith, andC.G. Farmilo. 1961. Essential oil from fresh
Cannabis Sativa and its use in identification. Nature 191:774-6.

Turner CE, ElSohly MA, Boeren EG. Constituents of Cannabis sativa L. ZVII.
A review of the natural constituents. J Nat Prod. 1980; 43:169-304.

Mediavilla, V., and S. Steinemann. 1997. Essential oil of Cannabis sativa L. strains. J Internat Hemp Assoc 4 (2):82-4.

Meier, C., Mediavilla, V. 1998. Factors influencing the yield and the quality of hemp (Cannabis sativa L.) essential oil. J Internat Hemp Assoc 5 (1):16-20.
ABSTRACT: The aim of this work was to assess the factors influencing the yield and the quality of hemp essential oil. Several strains were used to carry out field and greenhouse experiments, and as specimens for scent tests and chemical analysis of the distilled oils.
Yields of oil were highest at seeding rates of 5 kg/ha and when about a 50% of the crop had reached maturity. Pollination led to significantly lower yields, but is not easy to prevent in the field. Chemical composition showed almost no relationship to harvest dates or to scores on the scent tests. The best scent quality was always obtained from plants harvested one to three weeks before seed maturity (75% of seed matured). The interval during which both yield and quality were high was rather short and had to be assessed for each strain. The influence of other factors such as weather and harvest technique were also evaluated.
http://www.internationalhempassociation.org/jiha/jiha5107.html

Any comments welcome.
-SamS

Hola Sam,

Great idea..a little input to possible categories. These would sit in the 'popular' category.

Plant Population Improvements
Preservation of genetics / Conservation breeding
Breeding Basics (basic pollinations, punnet squares, bio assay selections)

Here is a link to a 'interactive game' that might help some folk understand punnet squares more easily. Definitely something for the popular section but interesting to those beginning to understand breeding. Here is the intro from that page..

Introduction: Punnett squares allow geneticists to determine the possible genotypes of offspring when the genotypes of parents are known. The genes of one parent are arranged across the top of the square, and the genes of the other parent are arranged down the side, much like a multiplication table. The possible genotypes of offspring are also determined in a manner similar to a multiplication table - by taking the gene represented on the top and the gene represented along the side and placing both in their corresponding boxes (see below).

http://library.thinkquest.org/17109/game.htm

This is a great thing guys, I think what we need first here is a good basic guide for breeding etc. just like HHF said, we have a nice load of info here at IC but its just all about arranging the data so that all info that one needs is easy to find, in its own place so to say, all the info should be very visible sticky threads and only mods can post so they stay clean and easy to read...peace guys..

Plant Breeding
Vol. 124 Issue 2 Page 167 April 2005
Sex-linked SSR markers in hemp
J. Rode, K. In-Chol, B. Saal, H. Flachowsky, U. Kriese, W. E. Weber
Sex-linked SSR markers in hemp
J. Rode1,
K. In-Chol2,
B. Saal1,
H. Flachowsky3,
U. Kriese4 and
W. E. Weber1,5
1 Institut für Pflanzenzüchtung und Pflanzenschutz, Martin-Luther-Universität Halle-Wittenberg, Ludwig-Wucherer-Str. 2, D-06099 Halle, Germany; 2 Center of Cell and Gene Engineering, Academy of Sciences, Ryonmesdong, Pyongyang, PR North Korea, Korea; 3 Institut für Obstzüchtung, BAZ, Pillnitzer Platz 3a, D-01326 Dresden, Germany; 4 KWS SAAT AG, Grimsehlstr. 31, D-37555 Einbeck, Germany; 5 Corresponding author, E-mail: weber@landw.uni-halle.de
Abstract
Hemp is a dioecious plant with sex chromosomes X and Y, the male sex being heterogametic. The quality of the fibre depends on the sex type. The sex chromosomes can be characterized by molecular markers. In this report, sex-linked simple sequence repeat (SSR) markers are described. One SSR marker was polymorphic in both the populations derived from single crosses, two other markers in but one of the two populations. Three alleles were detected for two SSR markers indicating polymorphism not only between X and Y, but also between different X chromosomes. In addition, several sex-linked RAPD markers were detected in one population. Recombination within the sex chromosomes was observed for nearly all markers.

Interesting comments on UVB in..

An elaboration on the phytochemical process that makes THC

April 2006 Update Of

MARIJUANA OPTICS, An elaboration on the phytochemical
process that makes THC, A Continuing Updating Manual
by Joe Knuc

The resin exuded by the glandular trichome forms a sphere (1) that encases the head cells. (2)

When the resin spheres are separated from the dried plant material by electrostatic (3) attraction and placed on a microscope slide illuminated with a 100W incandescent bulb, they appear very dark when observed through a 300X microscope. Since orange, red, and infrared are the component wavelengths of incandescent light, and since the absorption of light makes an object dark or opaque to the frequency of the incoming wave, one can conclude that these wavelengths are probably not directly involved in energizing the cannabinoid pathway. (4)

However, the resin sphere is transparent to ultraviolet radiation. (5)

The author found through trial and error that only one glandular
trichome (6) exhibits the phytochemical process that will produce the amount of THC associated with pain relief, appetite stimulation and anti-nausea; euphoria and hallucinations are side-effects, however. This trichome is triggered into growth by either of the two ways that the floral bract is turned into fruit. (7)

Click to expand...

http://www.onlinepot.org/medical/marijuanaoptics2006.htm

Novel male-specific molecular markers (MADC5, MADC6) in hemp
Euphytica Volume 127, Number 2 / September, 2002 209-218
Nándor*Bucherna1, Erzsébet*Kiss1, Hajnalka*Homoki1, Zsuzsanna*Finta-Korpelová2, Iván*Bócsa2, István*Nagy3 and László*E.*Heszky1*
(1)*
Dept. of Genetics & Plant Breeding, St. István University, Gödöllõ, Hungary
(2)*
Agricultural Research Institute, St. István University, Kompolt, Hungary
(3)*
Agricultural Biotechnology Center, Gödöllõ, Hungary

Abstract**Decamer RAPD primers were tested on dioecious and monoecious hemp cultivars to identify sex-specific molecular markers. Two primers (OPD05 and UBC354) generated specific bands in male plants. These two DNA fragments were isolated, cloned and sequenced. Both markers proved to be unique, since no sequence with significant homology to OPD05961 and UBC354151 markers were found in databases. These markers were named MADC3 (OPD05961) and MADC4 (UBC354151) (Male-Associated DNA from Cannabis sativa). The markers were converted into sequence-characterized amplified region (SCAR) markers. The SCAR markers correlated with the sex of the segregating F2 population and proved the tight linkage to the male phenotype. Results of F2 plant population analysis suggest these markers are to be linked to the Y chromosome.




Plant Breeding
Volume 120 Issue 4 Page 305 - August 2001
Flachowsky, Schumann, Weber, Peil (2001)
Application of AFLP for the detection of sex-specific markers in hemp
Plant Breeding 120 (4), 305–309.

Application of AFLP for the detection of sex-specific markers in hemp
1Institute of Plant Breeding and Plant Protection, Martin-Luther-University Halle-Wittenberg, Ludwig-Wucherer-Str. 2, D–06108 Halle, Germany. E-mail: peil@landw.uni-halle.de
Correspondence to: PEIL Institute of Plant Breeding and Plant Protection, Martin-Luther-University Halle-Wittenberg, Ludwig-Wucherer-Str. 2, D–06108 Halle, Germany. E-mail: peil@landw.uni-halle.de
Abstract
Two dioecious hemp accessions (Can18 and Can17) were tested by bulked segregant analysis for polymorphisms between male and female bulks with amplified fragment length polymorphisms. Thirty-nine primer combinations were tested and 20 of these yielded one to three male-specific bands. In contrast, no female-specific band was detected. Eight of these primer combinations were used for testing 80 progeny plants from a cross between two plants from Can18 and 30 plants from Can17. A total of 16 and 17 male-specific fragments were obtained for Can18 and Can17, respectively. Eleven fragments exhibited the same fragment size in both accessions. All male plants, but not one female plant, showed the respective polymorphic band with each of the eight primer combinations. Problems regarding sex determination under field conditions were successfully overcome by testing plants that had been grown in small pots in a greenhouse. The abundant number of potential markers for the male sex, their complete cosegregation with male plants and the absence of markers for the female sex support the presence of a male sex chromosome in hemp.


Botanical Journal of the Linnean Society
Volume 147 Issue 4 Page 387 - April 2005
MIRIAM ROTHSCHILD, GUNNAR BERGSTRÖM, STEN-ÅKE WÄNGBERG (2005)
Cannabis sativa: volatile compounds from pollen and entire male and female plants of two variants, Northern Lights and Hawaian Indica
Botanical Journal of the Linnean Society 147 (4), 387–397.

Cannabis sativa: volatile compounds from pollen and entire male and female plants of two variants, Northern Lights and Hawaian Indica
MIRIAM ROTHSCHILD1,
GUNNAR BERGSTRÖM2* and
STEN-ÅKE WÄNGBERG3
1Ashton Wold, Peterborough, PE8 5LZ, UK
2Ethological Chemistry and
3Botanical Institute, Göteborg University, Box 461, SE-40530 Göteborg, Sweden
*E-mail: oddsoxinventions@comhem.se
Abstract
Sixty-eight compounds were identified by coupled gas chromatography and mass spectrometry (GC-MS) in the chemosphere of Cannabis sativa L. pollen and entire male and female plants of two cultivated varieties, Northern Lights and Hawaian Indica. Twenty-one and 28 substances, respectively, were present in pollen of the two forms. To conserve the natural composition of volatiles a delicate headspace method was employed. The two varieties represent different chemotypes which distinguish themselves, in the main quantitatively, in the setup of volatiles from pollen and entire male and female plants. Twenty compounds were monoterpenes, including the five major components: ?-myrcene (E)-?-ocimene, terpinolene, ?-pinene and limonene; 25 were sesquiterpenes, and the other 23 were of mixed biogenetic origin, including 3-methyl-1-butanol and benzylalcohol which occurred only in pollen; two pyrazines occurred only in Northern Lights females. Besides being of interest in natural products chemistry, the results should have relevance for plant systematics and for the pharmaceutical and technical applications of Cannabis. We demonstrate that the pollen has a distinct chemical character in possessing two exclusive volatiles, while lacking seven compounds occurring in males and females of both variants.**© 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 147, (4) 387–397.

Journal of Forensic Sciences
Volume 51 Issue 2 Page 371 - March 2006
Shannon L. Datwyler Ph.D, George D. Weiblen Ph.D (2006)
Genetic Variation in Hemp and Marijuana (Cannabis sativa L.) According to Amplified Fragment Length Polymorphisms
Journal of Forensic Sciences 51 (2), 371–375.


Genetic Variation in Hemp and Marijuana (Cannabis sativa L.) According to Amplified Fragment Length Polymorphisms*
Shannon L. Datwyler, Ph.D.1,2; and
George D. Weiblen, Ph.D.2
1Department of Plant Biology, University of Minnesota, 1445 Gortner Avenue, Saint Paul, MN 55108.
2Present Address: Department of Biological Sciences, California State University, Sacramento, 6000 J Street, Sacramento, CA 95819.
Additional information and reprint requests:
George D. Weiblen, Ph.D
Department of Plant Biology
University of Minnesota
1445 Gortner Avenue
Saint Paul, MN 55108
E-mail: gweiblen@umn.edu
Abstract
ABSTRACT: Cannabis sativa L. (Cannabaceae) is one of the earliest known cultivated plants and is important in the global economy today as a licit and an illicit crop. Molecular markers distinguishing licit and illicit cultivars have forensic utility, but no direct comparison of hemp and marijuana amplified fragment length polymorphism (AFLP) has been made to date. Genetic variation was surveyed in three populations of fiber hemp and a potent cultivar of marijuana using AFLP markers. Ten primer pairs yielded 1206 bands, of which 88% were polymorphic. Eighteen bands represented fixed differences between all fiber populations and the drug cultivar. These markers have practical utility for (1) establishing conspiracy in the cultivation and distribution of marijuana, (2) identifying geographic sources of seized drugs, and (3) discriminating illegal, potent marijuana cultivars from hemp where the cultivation of industrial hemp is permitted.


Plant Breeding
Volume 115 Issue 5 Page 367 - November 1996
V. Faeti, G. Mandolino, P. Ranalli (1996)
Genetic diversity of Cannabis sativa germplasm based on RAPD markers
Plant Breeding 115 (5), 367–370.

Genetic diversity of Cannabis sativa germplasm based on RAPD markers
V. Faeti1,
G. Mandolino1
P. Ranalli1,2
1Istitute Sperimentale per le Colture Industriali, Via di Corticella 133,1–40129 Bologna, Italy
2Corresponding author
Abstract
*
Random amplified polymorphic DN A (RAPD) markers were generated from 13 cultivars and accessions of Cannabis sativa L. Approximately 200 fragments generated by 10 primers of arbitrary sequence were used to assess the level of DNA variation. Statistical analysis was performed using the Dice coefficient of similarity and principal coordinate analysis. The grouping of the accessions according to the cluster analysis was in good agreement with their origin and lines with common ancestors were grouped together. Principal coordinates 1 and 2 revealed a clear separation of Italian and Hungarian germplasm and a third group, including a mixture of genotypes coming from different places; the third coordinate separated the Korean group which is probably the most divergent germplasm. Variability within the two cultivars 'Carmagnola' and 'Fibranova1' was also shown, suggesting good possibilities for long–term selection work. RAPD markers provide a powerful tool for the investigation of genetic variation in cultivars/accessions of hemp.


Molecular Ecology Notes
Volume 3 Issue 1 Page 105 - March 2003
S. Gilmore, R. Peakall (2003)
Isolation of microsatellite markers in Cannabis sativa L. (marijuana)
Molecular Ecology Notes 3 (1), 105–107.

PRIMER NOTE
Isolation of microsatellite markers in Cannabis sativa L. (marijuana)
S. Gilmore*† and
R. Peakall†
*Centre for Forensic Science, Canberra Institute of Technology, PO Box 826, Canberra ACT 2601, Australia, †School of Botany and Zoology, Australian National University, Canberra ACT 0200, Australia
Correspondence: S. Gilmore. Fax: +61-2-62074105; E-mail: simon.gilmore@cit.act.edu.au
Abstract
*
We have identified 15 variable microsatellite loci in Cannabis sativa. In 48 samples from five fibre crop seed accessions, we detected an average of 10 alleles per locus (range 2–28) with mean heterozygosity of 0.68 (range 0.28–0.94). Significant genetic differentiation was found between accessions (FST*=*0.12, P<*0.001). These markers have utility for characterizing genetic diversity in cultivated and naturalized Cannabis populations.

I don't know what to say about the UVB paper MARIJUANA OPTICS. It has been around for a few years now and I first saw it 5 years ago. I will let others comment before I do. It can be posted if everyone wants it.

-SamS

Fibonacci Numbers and Nature

Fibonacci Numbers and Nature

Fibonacci Numbers and Nature

This page has been split into TWO PARTS.

This, the first, looks at the Fibonacci numbers and why they appear in various "family trees" and patterns of spirals of leaves and seeds.

The second page then examines why the golden section is used by nature in some detail, including animations of growing plants

http://www.mcs.surrey.ac.uk/Personal/R.Knott/Fibonacci/fibnat.html

Thanks HhF & FJ,
Keep them coming.
-SamS

synthesized ceramide is involved in cannabinoid-induced apoptosis

synthesized ceramide is involved in cannabinoid-induced apoptosis

De novo-synthesized ceramide is involved in cannabinoid-induced apoptosis
Teresa GÓMEZ DEL PULGAR , Guillermo VELASCO , Cristina SÁNCHEZ , Amador HARO and Manuel GUZMÁN1

Department of Biochemistry and Molecular Biology I, School of Biology, Complutense University, 28040 Madrid, Spain

D9-Tetrahydrocannabinol (THC) and other cannabinoids have been shown to induce apoptosis of glioma cells via ceramide generation. In the present study, we investigated the metabolic origin of the ceramide responsible for this cannabinoid-induced apoptosis by using two subclones of C6 glioma cells: C6.9, which is sensitive to THC-induced apoptosis; and C6.4, which is resistant to THC-induced apoptosis. Pharmacological inhibition of ceramide synthesis de novo, but not of neutral and acid sphingomyelinases, prevented THC-induced apoptosis in C6.9 cells. The activity of serine palmitoyltransferase (SPT), which catalyses the rate-limiting step of ceramide synthesis de novo, was remarkably enhanced by THC in C6.9 cells, but not in C6.4 cells. However, no major changes in SPT mRNA and protein levels were evident. Changes in SPT activity paralleled changes in ceramide levels. Pharmacological inhibition of ceramide synthesis de novo also prevented the stimulation of extracellular-signal-regulated kinase and the inhibition of protein kinase B triggered by cannabinoids. These findings show that de novo -synthesized ceramide is involved in cannabinoid-induced apoptosis of glioma cells.

http://www.biochemj.org/bj/363/0183/bj3630183.htm

Right on Sam,I put a sticky in the Breeders Lab about a week ago,hopefully we can link or compile there.
I did a couple searches the other day.Here's a link to a bunch of abstracts about Cannaboids and Chromatography:

http://www.ncbi.nlm.nih.gov/entrez/..._pubmed&from_uid=7463309&itool=ExternalSearch

JLP

A chemotaxonomic analysis of cannabinoid variation in Cannabis (Cannabaceae)
(American Journal of Botany. 2004;91:966-975.)
Karl W. Hillig2 and Paul G. Mahlberg

http://www.amjbot.org/cgi/content/full/91/6/966
---------------------------------------------------------
The Inheritance of Chemical Phenotype in Cannabis sativa L.
Genetics, Vol. 163, 335-346, January 2003
Etienne P. M. de Meijer,*,1 Manuela Bagatta,† Andrea Carboni,† Paola Cruci

http://www.genetics.org/cgi/content/full/163/1/335

Forensic Sci Int. 2006 Jun 2;159(2-3):132-40. Epub 2005 Sep 6.
DNA polymorphisms in the tetrahydrocannabinolic acid (THCA) synthase gene in "drug-type" and "fiber-type" Cannabis sativa L.

Kojoma M,
Seki H,
Yoshida S,
Muranaka T.
JYUGEI Institute (The Arboricultural Research Institute), University Forests, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 457 Kano, Minami-izu, Shizuoka 451-0304, Japan. kojoma@uf.a.u-tokyo.ac.jp
The cannabinoid content of 13 different strains of cannabis plant (Cannabis sativa L.) was analyzed. Six strains fell into the "drug-type" class, with high Delta-9-tetrahydrocannabinolic acid (THCA) content, and seven strains into the "fiber-type" class, with low THCA using HPLC analysis. Genomic DNA sequence polymorphisms in the THCA synthase gene from each strain were studied. A single PCR fragment of the THCA synthase gene was detected from six strains of "drug-type" plants. We could also detect the fragment from seven strains of "fiber-type" plants, although no or very low content of THCA were detected in these samples. These were 1638 bp from all 13 strains and no intron among the sequences obtained. There were two variants of the THCA synthase gene in the "drug-type" and "fiber-type" cannabis plants, respectively. Thirty-seven major substitutions were detected in the alignment of the deduced amino acid sequences from these variants. Furthermore, we identified a specific PCR marker for the THCA synthase gene for the "drug-type" strains. This PCR marker was not detected in the "fiber-type" strains.

Chem Pharm Bull (Tokyo). 2004 Jun;52(6):718-21.
Quantitative analysis of cannabinoids from Cannabis sativa using 1H-NMR.

Hazekamp A,
Choi YH,
Verpoorte R.
Division of Pharmacognosy, Institute of Biology, Leiden University, Einsteinweb 55, 2300 RA Leiden, The Netherlands. ahazekamp@rocketmail.com
A (1)H-NMR method has been developed for the quantitative analysis of pure cannabinoids and for cannabinoids present in Cannabis sativa plant material without any chromatographic purification. The experiment was performed by the analysis of singlets in the range of delta 4.0-7.0 in the (1)H-NMR spectrum, in which distinguishable signals of each cannabinoid are shown. Quantitation was performed by calculating the relative ratio of the peak area of selected proton signals of the target compounds to the known amount of the internal standard, anthracene. For this method no reference compounds are needed. It allows rapid and simple quantitation of cannabinoids with a final analysis time of only 5 min without the need for a pre-purification step.

pipeline,
Can you add the author and Journal and date info?

JLP, looks like a fine place to put it.
Thanks,

-SamS

Hillig, K.W. (2005) "A Systematic Investigation of Cannabis" (Doctoral Dissertation, University of Indiana, 2005).

Available from Proquest Dissertations and in print from UMI.

Abstract:

Botanists disagree whether Cannabis (Cannabaceae) is a monotypic or polytypic genus. A systematic investigation was undertaken to elucidate underlying evolutionary and taxonomic relationships with the genus. Genetic, morphological, and chemotaxonomic analyses were conducted on 157 Cannabis accessions of known geographic origin. Sample populations of each accession were surveyed for allozyme variation at 17 gene loci. Principal Component (PC) analysis of the allozyme allele frequencies revealed that most accessions were derived from two major gene pools corresponding to Cannabis Sativa L. and Cannabis Indica Lam. A third putative gene pool corresponds to Cannabis Ruderalis Janisch. Previous taxonomic treatments were tested for goodness of fit to the pattern of genetic variation. Based on these results, a working hypothesis for a taxonomic circumscription of Cannabis was proposed that is a synthesis of previous polytypic concepts. Putative intraspecific taxa were assigned to "biotypes" pending formal taxonomic revision. Genetic variation was highest in the hemp and feral biotypes and least in the drug biotypes. Morphometric traits were analyzed by PC and canonical variates (CV) analysis. PC analysis failed to differentiate the putative species, but provided objective support for recognition of infraspecific taxa of C. Sativa and C. Indica. CV analysis resulted in a high degree of discrimination of the putative species and infraspecific taxa. Variation in qualititative and quantatative levels of cannabidiol (CBD), tetrahydrocannabinol (THC), and other cannabinoids was determined, as were frequencies alleles that control CBD and THC biosynthesis. The patterns of variation support a two-species concept, but not recognition of C. Ruderalis as a separate species from C. Sativa. PC analysis of terpenoid variation showed that the wide-leaf drug (WLD) biotypes of C. Indica produced enhanced mean levels of guiaol and isomers of eudesmol, and is distinct from the other putative taxa. In summary, the results of this investigation show that a taxonomic revision of Cannabis is warranted. However, additional studies of putative wild populations are needed to further substantiate the proposed taxonomic treatment.

Field Crops Research
Volume 40, Issue 3 , March 1995, Pages 153-164

Copyright © 1995 Published by Elsevier Science B.V.
Plant density and self-thinning affect yield and quality of fibre hemp (Cannabis sativa L.)

H. M. G. van der Werfa, b, c, , M. Wijlhuizena and J. A. A. de Schutterb

a DLO Research Institute for Agrobiology and Soil Fertility (AB-DLO), P.O. Box 14, 6700 AA, Wageningen, Netherlands
b Wageningen Agricultural University, Department of Agronomy, Wageningen, Netherlands
c Research Station for Arable Farming and Field Production of Vegetables, Lelystad, Netherlands

Received 30 June 1994; accepted 7 November 1994. ; Available online 10 March 2000.




Abstract
To ascertain the reasons for the high plant mortality in fibre-hemp (Cannabis sativa L.) crops in the Netherlands changes in biomass yield, plant mortality and plant morphology were investigated in a hemp cultivar grown at initial densities of 10, 30, 90 and 270 plants m−2. At 90 plants m−2 this cultivar was compared with a high bast-fibre cultivar and a late-flowering cultivar. Rate of canopy establishment and early growth rate increased with increasing plant density. At 90 and 270 plants m−2, plants died as a result of self-thinning. Self-thinning was associated with a reduced crop growth rate. In self-thinning stands, dry biomass (B, g m−2) was related to density of surviving plants (D, m−2) as log B = 3.81 − 0.304 log D. At the same crop growth rate, the rate at which plants died from self-thinning was higher in hemp than in other herbaceous dicots. The proportion of stem in the total dry matter increased with increasing plant density. Stem yield was maximum at 90 plants m−2. Stem quality improved with increasing density as the bark content in the stem increased, but self-thinning reduced the bark content in the stem. Optimum plant density was close to that resulting after self-thinning. In hemp the relationship between yield and optimum plant density is approximated by the equation of its self-thinning line. The late-flowering cultivar yielded more than the other two cultivars because it grew faster during the latter part of the growing season.

Limeygreen- Check out my post......Already linked with that study.

wow I made a thread of this

wow I made a thread of this

From the one response I got, which was "???????????"

I presumed there was no interest whatsoever.


I am glad someone found the same info and found it worthy also, I was beginning to wonder if I was just too science minded.

pipeline said:

A chemotaxonomic analysis of cannabinoid variation in Cannabis (Cannabaceae)
(American Journal of Botany. 2004;91:966-975.)
Karl W. Hillig2 and Paul G. Mahlberg

http://www.amjbot.org/cgi/content/full/91/6/966
---------------------------------------------------------
The Inheritance of Chemical Phenotype in Cannabis sativa L.
Genetics, Vol. 163, 335-346, January 2003
Etienne P. M. de Meijer,*,1 Manuela Bagatta,† Andrea Carboni,† Paola Cruci

http://www.genetics.org/cgi/content/full/163/1/335

Click to expand...

This thread is a great idea!

Thanks for sharing the links and abstracts.

-BP-