scholarly journals The morphology of Cannabis sativa L. Achenes

2021 ◽  
Author(s):  
Steve Govinda Udai Naraine
Keyword(s):  
Cannabis Sativa ◽  
Morphological Characters ◽  
Life History Strategies ◽  
Plant Domestication ◽  
Phenotypic Differences ◽  
Evolution Of Life ◽  
Significant Divergence ◽  
High Concentrations ◽  
Herbarium Collections

Cannabis sativa L. has been domesticated for fibre, oilseed, and marijuana; it also occurs as ruderal plants. “Marijuana” refers to plants selected for high concentrations of the chemical tetrahydrocannabinol (THC), while “hemp” refers to plants low in concentration of THC and which are domesticated for either stem fibre or oilseed. In my first chapter I review the botany of cannabis, taxonomy and origins, ethnobotany, and crop ferality. In my second chapter, I performed a study where achenes (“seeds”) from herbarium collections representative of these classes of C. sativa were assessed for variation in morphological characters and pericarp resistance to fracture. Multivariate analysis of the data revealed significant divergence among the groups. In contrast to ruderal plants, domesticated plants (hemp or marijuana) possessed achenes that are significantly longer, heavier, covered with a less adherent perianth, and lacking a pronounced basal attenuation. These characteristics reflect traits that are advantageous in domesticated plants, and are consistent with the "domestication syndrome”. Marijuana achenes, in comparison with hemp achenes, are shorter and darker. Achenes of fibre cultivars are larger than the achenes of oilseed cultivars. Achenes of dioecious oilseed cultivars are larger than the achenes of monoecious oilseed cultivars. We propose several mechanisms by which this phenotypic divergence may have occurred, including potential differences in outcrossing rate and the evolution of life history strategies among C. sativa groups that deserve further exploration. While only one species of Cannabis merits recognition, we postulate these phenotypic differences in C. sativa are a result of domestication for different purposes. In my final chapter I discuss the limitations and future studies. This work contributes a more complete understanding of cannabis morphology to the greater body of literature on plant domestication.

scholarly journals The morphology of Cannabis sativa L. Achenes

2021 ◽  
Author(s):  
Steve Govinda Udai Naraine
Keyword(s):  
Cannabis Sativa ◽  
Morphological Characters ◽  
Life History Strategies ◽  
Plant Domestication ◽  
Phenotypic Differences ◽  
Evolution Of Life ◽  
Significant Divergence ◽  
High Concentrations ◽  
Herbarium Collections

Cannabis sativa L. has been domesticated for fibre, oilseed, and marijuana; it also occurs as ruderal plants. “Marijuana” refers to plants selected for high concentrations of the chemical tetrahydrocannabinol (THC), while “hemp” refers to plants low in concentration of THC and which are domesticated for either stem fibre or oilseed. In my first chapter I review the botany of cannabis, taxonomy and origins, ethnobotany, and crop ferality. In my second chapter, I performed a study where achenes (“seeds”) from herbarium collections representative of these classes of C. sativa were assessed for variation in morphological characters and pericarp resistance to fracture. Multivariate analysis of the data revealed significant divergence among the groups. In contrast to ruderal plants, domesticated plants (hemp or marijuana) possessed achenes that are significantly longer, heavier, covered with a less adherent perianth, and lacking a pronounced basal attenuation. These characteristics reflect traits that are advantageous in domesticated plants, and are consistent with the "domestication syndrome”. Marijuana achenes, in comparison with hemp achenes, are shorter and darker. Achenes of fibre cultivars are larger than the achenes of oilseed cultivars. Achenes of dioecious oilseed cultivars are larger than the achenes of monoecious oilseed cultivars. We propose several mechanisms by which this phenotypic divergence may have occurred, including potential differences in outcrossing rate and the evolution of life history strategies among C. sativa groups that deserve further exploration. While only one species of Cannabis merits recognition, we postulate these phenotypic differences in C. sativa are a result of domestication for different purposes. In my final chapter I discuss the limitations and future studies. This work contributes a more complete understanding of cannabis morphology to the greater body of literature on plant domestication.

Cultivation of New Emerging Agro-Nutritional Crop of Quinoa at Madinat al-Hikmah Karachi, Sindh, Pakistan

2017 ◽  
Vol 10 (1) ◽  
pp. 70-81 ◽  
Author(s):  
Muhammad Afzal Rizvi ◽  
Syed Abid Ali ◽  
Iqra Munir ◽  
Kousar Yasmeen ◽  
Rubina Abid ◽  
...  
Keyword(s):  
Arid Zone ◽  
Good Health ◽  
Morphological Characters ◽  
Morphological Data ◽  
Low Concentrations ◽  
Sindh Province ◽  
High Concentrations ◽  
Elemental Accumulation ◽  
Semi Arid ◽  
Good Agreement

Aim: Quinoa is a popular source of protein, minerals and alternative to traditional grains. The objective of this study is to introduce the Quinoa in the semi-arid zone of Sindh province of Pakistan. Method: A variety of NARC-9 from the agricultural Punjab province was cultivated and subjected to analyze the growth, morphological characters of the varieties obtained, saponin, protein and the elemental composition viz. Cd, Cu, Fe, K, Na, Pb, and Zn. Result: The result demonstrated the optimum growth and no disease were found in the experimental area. At least three major varieties of quinoa were obtained. Seed morphological data of these three quinoa cultivars were collected. The average saponin levels were quite reasonable. Overall proteins band pattern revealed very high polymorphism in quinoa cultivars and the results were also in good agreement with earlier studies. Conclusion: All quinoa cultivars of Madinat al-Hikmah showed high concentrations of albumin than globulin concentrations (i.e. 48-52% and 24-27%, respectively) as compared to control seeds from market that had similar concentrations of the two fractions i.e. 35.58% and 37.68%, respectively. Likewise, low concentrations of prolamin 14-16% and glutelin 11-12% compared to control seeds 13% rank our crop much better quality than the imported one in the market. The trend of elemental accumulation was followed as K >Na >Fe >Zn >Cu >Pb >Cd, while for comparison it was Na >K >Zn >Fe >Cu >Pb >Cd >Pb for wheat grown under similar conditions. Traditional grains together make a major contribution to the total nutritional element intake of the average Pakistani citizen through diet, not only because of large amounts consumed, but also in part by suitable levels of their proteins and elemental up take for good health. Thus the successful cultivation of quinoa in the semi-arid zone of Sindh will certainly prove beneficial.

scholarly journals Evolution of Sex Determination in Caenorhabditis: Unusually High Divergence of tra-1 and Its Functional Consequences

Genetics ◽  
1996 ◽  
Vol 144 (2) ◽  
pp. 587-595 ◽  
Author(s):  
Mario de Bono ◽  
Jonathan Hodgkin
Keyword(s):  
Sex Determination ◽  
Germ Line ◽  
Amino Acid Identity ◽  
Evolution Of Sex ◽  
Phenotypic Differences ◽  
C Elegans ◽  
Functional Studies ◽  
Somatic Gonad ◽  
Functional Consequences ◽  
Significant Divergence

Abstract The tra-1 gene is a terminal regulator of somatic sex in Caenorhabditis elegans: high tra-1 activity elicits female development, low tra-1 activity elicits male development. To investigate the function and evolution of tra-1, we examined the tra-1 gene from the closely related nematode C. briggsae. Ce-tra-1 and Cb-tra-1 are unusually divergent. Each gene generates two transcripts, but only one of these is present in both species. This common transcript encodes TRA-1A, which shows only 44% amino acid identity between the species, a figure much lower than that for previously compared genes. A Cb-tra-1 transgene rescues many tissues of tra-1(nul1) mutants of C. elegans but not the somatic gonad or germ line. This transgene also causes nongonadal feminization of XO animals, indicating incorrect sexual regulation. Alignment of Ce-TRA-1A and Cb-TRA-1A defines several conserved regions likely to be important for tra-1 function. The phenotypic differences between Ce-tra-1(null) mutants rescued by Cb-tra-1 transgenes and wild-type C. elegans indicate significant divergence of regulatory regions. These molecular and functional studies suggest that evolution of sex determination in nematodes is rapid and genetically complex.

scholarly journals Cost of autotomy drives ontogenetic switching of anti-predator mechanisms under developmental constraints in a land snail

2012 ◽  
Vol 279 (1748) ◽  
pp. 4811-4816 ◽  
Author(s):  
Masaki Hoso
Keyword(s):  
High Efficiency ◽  
Shell Growth ◽  
Land Snail ◽  
Life History Strategies ◽  
Body Parts ◽  
Developmental Constraint ◽  
Developmental Constraints ◽  
Evolution Of Life ◽  
Snake Range ◽  
In The Wild

Autotomy of body parts offers various prey animals immediate benefits of survival in compensation for considerable costs. I found that a land snail Satsuma caliginosa of populations coexisting with a snail-eating snake Pareas iwasakii survived the snake predation by autotomizing its foot, whereas those out of the snake range rarely survived. Regeneration of a lost foot completed in a few weeks but imposed a delay of shell growth. Imprints of autotomy were found in greater than 10 per cent of S. caliginosa in the snake range but in only less than 1 per cent out of it, simultaneously demonstrating intense predation by the snakes and high efficiency of autotomy for surviving snake predation in the wild. However, in experiments, mature S. caliginosa performed autotomy less frequently. Instead of the costly autotomy, they can use defensive denticles on the inside of their shell apertures. Owing to the constraints from the additive growth of shells, most pulmonate snails can produce these denticles only when they have fully grown up. Thus, this developmental constraint limits the availability of the modified aperture, resulting in ontogenetic switching of the alternative defences. This study illustrates how costs of adaptation operate in the evolution of life-history strategies under developmental constraints

A revision of Rhaponticoides (Asteraceae, Cardueae–Centaureinae) from Iran

Phytotaxa ◽  
2015 ◽  
Vol 213 (2) ◽  
pp. 87 ◽  
Author(s):  
Kazem Negaresh ◽  
SAYED MOHAMMAD REZA KHOSHROO ◽  
ROYA KARAMIAN ◽  
MOHAMMAD REZA JOHARCHI
Keyword(s):  
Geographical Distribution ◽  
Morphological Characters ◽  
Identification Key ◽  
Full Description ◽  
New Combinations ◽  
Taxonomic Review ◽  
Herbarium Collections ◽  
First Time

A taxonomic review of Rhaponticoides in Iran is based on morphological characters of the specimens from the authors’ expeditions and other herbarium collections. Rhaponticoides lachnopus, R. schmidii, R. sect. Iranicae and R. sect. Ruthenicae are proposed as new combinations. Full description for the genus Rhaponticoides and R. sect. Iranicae and R. sect. Ruthenicae are presented for the first time here. Three names, R. lachnopus, R. ruthenica and its synonym, are typified. A synopsis with recognized sections and species, relevant synonyms, type citations, lists of specimens examined and an identification key are provided for the genus Rhaponticoides in Iran. In addition, some notes about ecology and habitat of Rhaponticoides especially in Iran are given. Finally, the geographical distribution of all the 4 species recognized in Iran is presented and mapped.

Reestablishment of Cabomba schwartzii (Cabombaceae), an aquatic plant species endemic to the Brazilian Amazon

Phytotaxa ◽  
2018 ◽  
Vol 367 (3) ◽  
pp. 245 ◽  
Author(s):  
TIAGO D. M. BARBOSA ◽  
RAFAELA J. TRAD ◽  
MIKLOS M. BAJAY ◽  
MARIA I. ZUCCHI ◽  
MARIA DO CARMO E. DO AMARAL
Keyword(s):  
Geographical Distribution ◽  
Plant Species ◽  
Genetic Study ◽  
Aquatic Plant ◽  
Brazilian Amazon ◽  
Distinct Species ◽  
Morphological Characters ◽  
Species Description ◽  
Dichotomous Key ◽  
Herbarium Collections

Cabomba schwartzii was described by Rataj in 1977. The species discovered in the Brazilian Amazon was said to differ from other Cabomba species in having two sepals, two petals and a lobate petal base. According to the 1991 study of Ørgaard, C. schwartzii is similar to C. aquatica in other morphological characters (C. aquatica has flowers with three sepals and three petals) and since variation in number of floral parts is common in the genus, Ørgaard synonymized both species. After an analysis of C. schwartzii type material, other herbarium collections and location of four populations (two with C. schwartzii characteristics and two with C. aquatica characteristics), we conducted an integrated morphological and genetic study to evaluate whether or not C. schwartzii is a distinct species from C. aquatica. The results reveal the species to be distinct from each other and therefore C. schwartzii should be reestablished. The floral formula for C. schwartzii is K2 C2 A2+2 G1, versus K3 C3 A3+3 G2 for C. aquatica. A detailed species description and the geographical distribution of C. schwartzii are presented with a dichotomous key to distinguish both species, together with illustrations.

scholarly journals Inheritance of Biochemical and Morphological Characters Associated with Two-spotted Spider Mite Resistance in Pelargonium ×hortorum

1997 ◽  
Vol 122 (3) ◽  
pp. 373-379 ◽  
Author(s):  
Richard Grazzini ◽  
Donald Walters ◽  
Jody Harmon ◽  
David J. Hesk ◽  
Diana Cox-Foster ◽  
...  
Keyword(s):  
Spider Mite ◽  
Genetic Model ◽  
Glandular Trichomes ◽  
Glandular Trichome ◽  
Morphological Characters ◽  
Spider Mites ◽  
Trichome Density ◽  
Anacardic Acids ◽  
High Concentrations ◽  
Two Spotted Spider Mite

Diploid zonal geraniums (Pelargonium ×hortorum) are able to resist attack by small arthropod pests such as the two-spotted spider mite (Tetranychus urticae Koch) when exudate produced by tall glandular trichomes contains a high percentage of ω5-unsaturated anacardic acids. Trichomes of susceptible plants exude primarily saturated anacardic acids. Inbred mite-resistant and -susceptible geraniums were reciprocally crossed and the F1, F2, and backcross generations were examined for anacardic acid composition and trichome density. Selected F2 plants were bioassayed for resistance to two-spotted spider mites. High concentrations of ω5-unsaturated anacardic acids in resistant plants are conditioned by a single dominant allele. We propose that inheritance of tall glandular trichome density can be controlled by a small number of loci (possibly as few as one) exhibiting codominance. F2, with low densities of tall glandular trichomes and producing ω5-unsaturated anacardic acids, displayed effective resistance to two-spotted spider mites as measured by mite mortality and fecundity. A genetic model for the biosynthesis of anacardic acids is proposed.

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