Leaf Blade Morphology Research Articles

Chemophenetics as a Tool for Distinguishing Morphotypes of Annona emarginata (Schltdl.) H. Rainer.

Annona emarginata (Annonaceae) has two morphological variations (A. emarginata 'mirim' and A. emarginata 'terra-fria'). The species has agricultural value and produces specialized metabolites of pharmacological interest. The objective of this work was to analyze whether chemical and morphological differences contribute to differentiate A. emarginata 'terra-fria' from A. emarginata 'mirim', as chemophenetic variations of A. emarginata. The analysis of chemical compounds was based on the quantification, profile of root alkaloids and on the leaves volatile profile, together with morphometric analyses of the leaf blade. The samples were collected in three phenological stages (flowering, fruiting, and vegetative) at two places in São Paulo, Brazil. Differences in the composition of the alkaloid profile and leaf volatiles (in both places and in the three phenological stages) allowed us to separate the two morphotypes by multivariate statistical analysis. These differences agreed with the leaf blade morphology and flower color. This first chemophenetic report of A. emarginata demonstrates that, in addition to morphological variations, the specialized metabolism of roots and leaves can be phytochemical characters, which suggest the existence of at least morphochemotypes of A. emarginata.

Novelties in Lepidaploinae (Asteraceae, Vernonieae) from the easternmost campos rupestres of Minas Gerais, Brazil: two new species and a range expansion

Background – Recent collection efforts in Serra do Padre Ângelo, Pico da Aliança, and Sete Salões State Park, all located in the state of Minas Gerais, have uncovered many botanical and zoological novelties. The region is an outlying campos rupestres area inserted in the Atlantic Forest phytogeographic domain, with its flora mostly related to that of the core campos rupestres area in the Espinhaço Range. Three species of Asteraceae, one of the most representative families in the campos rupestres, have been recently described for the area. Here we report two new species from the genera Lepidaploa and Lessingianthus and one range extension in Lessingianthus, both from subtribe Lepidaploinae.Methods – This study was based on specimens from the herbaria HUFU, MBML, SPF, UFP, and on field observations. Morphological observations and measures were taken following standard practices. Preliminary conservation assessments are based on field observations and spatial analyses (i.e. extent of occurrence, area of occupancy), following IUCN guidelines and criteria.Results – Two new species are described: Lepidaploa campirupestris, related to Lepidaploa aurea, differing from the latter by leaf indumentum, pedunculate heads, and number of florets; and Lessingianthus petraeus, related to Lessingianthus adenophyllus, but differing by leaf position and leaf blade morphology. We also report a range extension for Lessingianthus squamosus, previously known only for the state of Espírito Santo, ca 200 km away. Our results shed light on the interesting biogeography of the region, which mostly contains components of other campos rupestres areas intermixed with typical inselberg vegetation. It also highlights the importance of compiling floristic inventories in poorly collected localities and the need for conservation strategies for this biodiverse region.

Changes in leaf blade morphology and anatomy caused by clomazone and saflufenacil in Setaria viridis, a model C4 plant

Clomazone and saflufenacil are herbicides extensively used worldwide to weed control. We studied the effects of these two herbicides on morphoanatomical parameters of Setaria viridis. Plants were sprayed with four concentrations of each herbicide (clomazone: 500, 1000, 1500 and 2000 g of active ingredient (ai) ha−1 and saflufenacil: 49, 98, 147 and 196 g ai ha−1) besides control (without spraying) 20 days after transplantation. The experimental design was completely randomized with five replicates per treatment. Pigment content, visible injuries, morphological and ultrastructural changes were evaluated. No signs of tolerance to either of the tested herbicides were observed. Clomazone caused a decrease in photosynthetic pigment content over time, mostly in young leaves, leading to an “albino” like appearance. There was a reduction in the number of grana in the chloroplasts of mesophyll cells (MC) in necrotic areas. Saflufenacil reduced chlorophyll content, impairing energy absorption in the antenna complex. Injuries to foliar tissues, such as necrosis and depigmentation, were visible as early as 24 h after herbicide application. Bundle sheath chloroplasts (BSC) and MC were completely deformed. The data support the use of S. viridis as a model plant for studies on herbicide effects in C4 monocots.

Two new species of Timonius (Guettardeae: Rubiaceae) from Samar Island, the Philippines

ABSTRACT Two new Philippine endemic species of Timonius are described and illustrated: T. noli-tangere J.G.Chavez, Alejandro and Meve, and T. sulitii Merr. and Quisumb. ex J.G.Chavez and Tandang; both have been found on the island of Samar. Timonius noli-tangere is characterized by its opposite to whorled phyllotaxy, variable leaf blade morphology, reddish and verrucose calyces and subsessile pistillate inflorescences; while T. sulitii can be easily recognized by its widely ovate to suborbicular chartaceous leaves with silky underside, costate and tuberculate fruits with schizogenous cavity, and U-shaped orientation of pyrenes in longitudinal section of the fruit. The distribution, ecology and conservation status of the two species are discussed.

ОЦІНКА ПІСЛЯДІЇ МУТАГЕННИХ ЧИННИКІВ НА МІНЛИВІСТЬ ЯКІСНИХ ОЗНАК, ЩО ВИЗНАЧАЮТЬ ФЕНОТИП ЛИСТКОВОЇ ПЛАСТИНКИ МУТАНТНИХ РОСЛИН САЛАТУ ЛИСТКОВОГО

Мета. Визначити дію мутагенних чинників на формування якісних ознак, які визначають фенотип листкової пластинки та провести порівняльний кореляційний аналіз між проявом якісних і кількісних ознак генотипів салату листкового мутантного походження. Методи. Непараметричної статистики, польової оцінки, розрахунково–аналітичні. Результати. Встановлено особливості дії фізичного і хімічного мутагенезу на фенотиповий прояв якісних ознак, що визначають морфологію листкової пластинки салату листкового. Визначено ступінь розбіжності прояву якісних ознак залежно від дії мутагенного чинника між вихідними формами і похідними від них мутантними генотипами. На основі кореляційного аналізу встановлено важливі для селекційного процесу зв’язки між якісними і кількісними ознаками у досліджених генотипів. Встановлено, що за проявом асоціації ознак, які визначають фенотип листкової пластинки найбільш контрастними порівняно із вихідною формою виявилися 2 мутантні зразки – [Сніжинка (ДМС, 6 год.), мф-1] (К-7392(1)) (rs = 0,43) та [Сніжинка (7 кР)] (К-7402) (rs = 0,31). Висновки. Досліджені кореляційні зв’язки дають можливість проводити добір високопродуктивних генотипів салату листкового на ранніх етапах онтогенезу рослин за асоціацією якісних ознак, що визначають фенотип листкової пластинки. Особливо корисним є встановлений, статистично достовірний кореляційний зв’язок, між інтегральним показником для сукупності якісних ознак “середній індекс для вибірки” та рівнем кількісних ознак “найбільша довжина листка” і “урожайність ” (rs = -0,51…0,49), що є важливим для відбору оцінки високопродуктивних генотипів салату листкового. На основі мутантних зразків салату листкового створено новий високопродуктивний сорт Мажор, який перевищив сорт-стандарт Сніжинка за комплексом цінних кількісних ознак. Урожайність нового сорту становить 10,0 т/га при 6,14 т/га у стандарту. Період від масових сходів до товарної стиглості у нового сорту становить 17 діб, у сорту-стандарту Сніжинка до 23 діб.

Effects of elevated atmospheric CO2 concentration on morphology of leaf blades in Chinese yam

ABSTRACTThe effects of elevated carbon dioxide concentration on the morphology of leaf blades in two Chinese yam lines under different temperature conditions were determined. Plants were grown under two [CO2] levels, ambient (about 400 µmol mol−1) and elevated (ambient + 200 µmol mol−1) in the daytime, and two mean air temperature regimes, approximately ambient temperature (22.2°C) and high temperature (25.6°C). The palisade layer was thicker under elevated [CO2] than under ambient [CO2] in both temperature regimes, and the whole yam leaf blade was thicker under elevated [CO2] than under ambient [CO2] in the approximately ambient temperature regime. The numbers of chloroplasts per palisade cell and spongy cell as well as per unit profile area of palisade cell, number of starch grains per chloroplast, profile area of the starch grain, and starch-to-chloroplast area ratio in both palisade and spongy cells were higher under elevated [CO2] than under ambient [CO2] in both temperature regimes. Furthermore, the stomatal density on the abaxial side of the leaf blade in Chinese yam was greater under elevated [CO2] than under ambient [CO2] under both temperature regimes, and stomatal-pore length was higher under elevated [CO2] than under ambient [CO2] in the approximately ambient temperature regime. These results indicate that elevated [CO2] positively affects the photosynthetic apparatus. The results of this study provide information for understanding the response characteristics of the leaf blade under elevated [CO2] and a possible explanation for the positive photosynthetic responses of Chinese yam to elevated [CO2] in our previous study.List of Abbreviations:[CO2]: carbon dioxide concentration

Effect of surfactants and leaf surface morphology on the evaporation time and coverage area of ZnIDHA droplets

The aim of the study was to determine the effects of the addition of surfactants to ZnIDHA fertilizer on the area of leaf coverage and water evaporation time taking into account the morphology of leaf blades. The effect of three surfactants (polyglucoside, alcohol EO (ethylene oxide) and trisiloxane) on the size of the leaf coverage area and evaporation time was compared. Adaxial leaf surfaces of maize (Zea mays L. `Wilga`), wheat (Triticum aestivum `Adana-99`) and rapeseed (Brassica napus L. `F1`) were analyzed by scanning electron microscopy and laser scanning confocal microscopy. The contact angle for aqueous ZnIDHA solutions with and without the addition of surfactants was determined. Measurements of droplet evaporation time and area of leaf coverage were conducted at the relative humidity of 60±1%. The adaxial surfaces of wheat and rapeseed leaves used in the study can be classified as highly non-wettable, whereas maize leaves are no-wettable. Out of the surfactants under study, the largest leaf coverage area was observed when adding the trisiloxane surfactant. Regardless of the surfactant used, the leaf coverage area decreased and the evaporation time increased for fertilizer droplets applied to the maize, rapeseed and wheat leaves. This study demonstrated that the addition of surfactants to the fertilizer solution increases the wettability of the adaxial leaf surface and induces a strong capillary effect which determines the direction of spread of fertilizer droplets. In addition to the amount of trichomes and waxes, also the capillary effect has a significant impact on water evaporation time and the area of leaf coverage by fertilizer droplets.

Formation of radial symmetric needle-like rosette leaves in Arabidopsis

AbstractIn the bodies of seed plants, lateral organs of the shoot, for example cotyledons, leaves, and floral organs, are determinate and exhibit localized planer growth resulting in breaking of radial symmetry and asymmetric development. Localized planer growth in the leaf generates the leaf blade, the principle site of photosynthesis in most plants. Development of flat and expanded lamina is an important physiological process. In these processes, a few kind of meristems cooperate with regulating leaf development. In this work, with transfer sense ASL11, sense ASL38 and antisense ASL15 under 35S promoter to to Arabidopsis (Col-0), we found a series of radial symmetric needle-like rosette leaves. By analyzing the anatomical and the epidermal cell features, our data suggests that in these malformed leaf blades, a few meristem tissues all can be suppressed or accelerated, and normal leaf blade morphology disappears. Pro ASL11:GUS expression further suggests that this process may be triggered by misexpression of a few transcription factors (Tfs).

SELECTION OF ALPINIA AS CUT FOLIAGE

Currently the diversity of species used as cutting foliage in floriculture is small compared to the number considered for ornamental foliage. This is due to the lack of information about quality, postharvest durability, consumer acceptance by the market and large-scale cultivation techniques. The aim of this work was to screen Alpinia species for their use as cut foliage. We evaluated 8 Alpinia genotypes (A. zerumbet, A. sanderae, A. purpurata ‘Pink Ginger’, ‘Kimi’, ‘King’, ‘Eileen Macdonald’, ‘Red Ginger’, ‘Queen’) for their postharvest durability, senescence symptoms, fresh weight and leaf blade morphology. The vase life of leaves varied from 6 to 49 days depending on the different types and position on the stem. The loss of visual quality and fresh weight was progressive over the vase life period and was affected by the senescence process. Larger and wider leaves were identified in the apical and middle positions of the stem. A. zerumbet genotypes were more adequate for use as cut foliage; as the leaves of A. purpurata and A. sanderae had a shorter vase life.

Effects of MULTIFOLIATE-PINNA, AFILA, TENDRIL-LESS and UNIFOLIATA genes on leafblade architecture in Pisum sativum.

In order to dissect the genetic regulation of leafblade morphogenesis, 16 genotypes of pea, constructed by combining the wild-type and mutant alleles of MFP, AF, TL and UNI genes, were quantitatively phenotyped. The morphological features of the three domains of leafblades of four genotypes, unknown earlier, were described. All the genotypes were found to differ in leafblade morphology. It was evident that MFP and TL functions acted as repressor of pinna ramification, in the distal domain. These functions, with and without interaction with UNI, also repressed the ramification of proximal pinnae in the absence of AF function. The expression of MFP and TL required UNI function. AF function was found to control leafblade architecture multifariously. The earlier identified role of AF as a repressor of UNI in the proximal domain was confirmed. Negative control of AF on the UNI-dependent pinna ramification in the distal domain was revealed. It was found that AF establishes a boundary between proximal and distal domains and activates formation of leaflet pinnae in the proximal domain.

The transcription factor AtGRF5 and the transcription coactivator AN3 regulate cell proliferation in leaf primordia of Arabidopsis thaliana

The development of the flat morphology of leaf blades is dependent on the control of cell proliferation as well as cell expansion. Each process has a polarity with respect to the longitudinal and transverse axes of the leaf blade. However, only a few regulatory components of these processes have been identified to date. We have characterized two genes from Arabidopsis thaliana: ANGUSTIFOLIA3 (AN3), which encodes a homolog of the human transcription coactivator SYT, and GROWTH-REGULATING FACTOR5 (AtGRF5), which encodes a putative transcription factor. AN3 is identical to GRF-INTERACTING FACTOR1 (AtGIF1). The an3 and atgrf5 mutants exhibit narrow-leaf phenotypes due to decreases in cell number. Conversely, cell proliferation in leaf primordia is enhanced and leaves grow larger than normal when AN3 or AtGRF5 is overexpressed. Both genes are expressed in leaf primordia, and in the yeast two-hybrid assay, the gene products were found to interact with each other through their N-terminal domains. These results suggest that AN3 and AtGRF5 act together and are required for the development of appropriate leaf size and shape through the promotion and/or maintenance of cell proliferation activity in leaf primordia.

Feeding preferences, seasonal gut repletion indices, and diel feeding patterns of the sea urchin Tripneustes gratilla (Echinodermata: Echinoidea) on a coastal habitat off Toliara (Madagascar)

The feeding biology of the echinoid Tripneustes gratilla from a seagrass bed off Toliara, on the south-west coast of Madagascar, was investigated during the summer and winter seasons. Repletion indices of the gut of T. gratilla varied seasonally, in such a way that higher amounts of food occurred in the gut in winter than in other seasons. Conversely, a more detailed analysis of one summer and one winter sample of the gut tissue dry weights revealed higher weights in summer (February) than in winter (August). This was interpreted as a varying capability of nutrient storage and closely related to the feeding activity of the echinoid. This inverse relationship between feeding activity and nutrient storage was suggested to be dependent on gonadal growth. Indeed, higher food consumption was observed during the post-spawning period (August), that is, when most of the energy accumulated was used up for gonadal growth. Low feeding activity occurred when a sufficient amount of energy was accumulated in gut tissues (February), the time corresponding to the initiation of gonadal growth. Investigations on the feeding habits, using Ivlev's electivity index, revealed preferential feeding of T. gratilla on Syringodium isoetifolium, the dominant seagrass species found in the gut. This was partly related to the higher availability of that particular seagrass species in the field. However, its soft and terete leaf blade's morphology also makes it easier to manipulate and ingest. Studies on the feeding behaviour indicated the presence of a diel feeding cycle in T. gratilla individuals in both summer and winter seasons. Yet, its pattern varied between the two studied months (one summer and one winter) as the cycle was less contrasted during period of active feeding, i.e. in winter compared to summer. This study provides novel information on how intrinsic factors, such as physiological state, can govern the feeding activity of T. gratilla living in a seagrass habitat.

Phenology and growth cycle of annual subtidal eelgrass in a subtropical locality

This study describes the phenology, life cycle and reproductive potential of Zostera marina L. (eelgrass) in Bahı́a Concepción, the southernmost population on the west coast of the Gulf of California. Z. marina populations in the Gulf of California are the unique annual subtidal meadows existing only in the coldest season of the year, from December to May, and surviving the adversely warm summer season as seeds. The maximum shoot density was 2334 shoots per square meter in January, the minimum recorded during the growth season was 664 shoots per square meter in May. Before December and after May no living plants were found. Until March, the percentage cover of the meadow was up to 90%, in April some patches of dead shoots were found (16%) and in May the meadow disappeared. Several growth variables, such as above-ground biomass, rhizome branching, leaf-blade morphology, and leaf area index, showed that the main vegetative growth was in the period December–January. The appearance of the first flowering shoots was in late January and the first fruit appearance was observed in March. The presence of flowers was observed from February to May. Fruit production was maximum in late March (21 fruits per shoot), decreasing later to eight fruits per shoot due to the release of seeds. Seed production was estimated to be 30,000 seeds per square meter.

Genetic analyses of the formation of the serrated margin of leaf blades in Arabidopsis: combination of a mutational analysis of leaf morphogenesis with the characterization of a specific marker gene expressed in hydathodes and stipules.

Developmental control of the formation of the serrated margin of leaf blades was investigated. First, the expression was characterized of a marker gene encoding beta-glucuronidase in strain #1-35-38, a transgenic strain of Arabidopsis thaliana (L.) Heynh, derived by the use of a previously described transposon-tagging system. In strain #1-35-38, expression of the marker gene was tissue-specific, being restricted to stipules and the toothed margins of laminae. Using this transgenic marker gene, we examined the development of leaf blade margins in Arabidopsis. We compared the pattern of expression of the marker gene in the leaves of the wild-type plant with that in plants carrying the asymmetric leaves1 (as1) mutation, which causes dramatic changes in leaf-blade morphology in Arabidopsis. The as1 mutant showed normal morphology of early leaf primordia. The mutation affected the development of leaf segmentation in Arabidopsis without any change in the number or morphology of cells in laminae. The as1 mutation affected leaf morphology independently of mutations in other genes known to affect leaf morphogenesis, such as the acaulis1 mutation and the angustifolia mutation. Based upon these results, the development of the morphology of leaf margins in Arabidopsis is discussed.

Leaf folding behaviour of Cnaphalocrocis medinalis (Guenee) and Marasmia patnalis Bradley, and the influence of rice leaf morphology on damage incidence

The leaf-folding behaviour of the pyralid rice leaf-folders (RLF), Cnaphalocrods medinalis (Guenee) and Marasmia patnalis Bradley, and the mechanism of fold construction were studied at the Bangladesh Rice Research Institute's experimental farm at Gazipur, Bangladesh during 1992 and 1993. Mature RLF larvae (instars III–V) usually folded rice leaves longitudinally with the abaxial surface inside the folds, while younger instars partially rolled the leaf edges. Folds were made along the middle portion of upper leaves. Larvae faced difficulties in making folds on narrower leaves which probably afforded less protection from harsh weather and natural enemies. These studies and observations broadened the understanding and knowledge regarding the actual procedure of leaf folding and led to the development of a hypothesis that rice plants having narrow leaf blades may offer resistance to RLF. A field test with 16 rice varieties and breeding lines with differences in leaf blade width and length correlated with the hypothesis. Tests also indicated that longer and tougher leaf blades might also contribute to resistance. It appeared that rice leaf blade morphology i.e. width, length, and toughness, may play a vital role in resistance against RLF. RLF resistance in TKM6 is suspected to be a combination of antixenosis and antibiosis.

Performance of morphologically diverse orchardgrass clones in spaced and sward plantings

AbstractThis study was conducted to determine effects and interactions of plant density on digestibility and plant morphology of diverse orchardgrass (Dactylis glomerata L.) clones. Propagules of ten orchardgrass clones with contrasting morphology from two maturity groups (inflorescence emergence differed by 8d) were evaluated in sward (0·15‐m centres) and spaced (0·60‐m centres) plantings. Plants were harvested from spring growth on a common date near anthesis and from summer growth when about 5 weeks of forage growth had accumulated. The plants were separated into morphological parts before measuring their size and in vitro digestible dry matter (IVDDM). There were few plant density × orchardgrass clone interactions, and correlation coefficients of clones grown at the two plant densities generally were high (e.g. 0·87 in spring and 0·67 in summer for IVDDM of total herbage). Plant density had little effect on morphology of leaf blades from reproductive tillers, but leaf blades of vegetative tillers were 12% (spring) and 22% (summer) longer from sward than from spaced plantings. Moreover, reproductive tillers were 26% taller in sward than in spaced plantings. Also, leaf blades of vegetative tillers in spring growth were more than twice as long, of similar width and 65% thicker than leaf blades from reproductive tillers. Because divergent genotypes respond similarly to plant density, it is concluded that observations taken in spaced plantings of orchardgrass can be used to make inferences about relative differences in sward plantings for the traits studied.

COMPARATIVE ONTOGENY OF A WILD CUCURBIT AND ITS DERIVED CULTIVAR.

Most previous studies of evolutionary modification of form in plants have focused primarily on individual organs or flowers. Few have investigated the role of evolutionary changes in timing or position at the level of whole plant ontogeny. This study compares ontogenies of the primary shoots of two subspecies of Cucurbita argyrosperma, one a cultivar and the other its wild progenitor. Differences in flowering times between these subspecies suggested that the cultivar may have evolved from the wild subspecies via heterochronic processes leading to paedomorphosis. Analyses showed that both subspecies are similar in vegetative architecture and rates of leaf production. Earlier flowering in the cultivar, both in terms of position and absolute time, appears to have arisen through progenesis. Initial observations of leaf blade morphology led to the hypothesis that paedomorphosis and gigantism also may have been involved in the evolution of leaf blade shape in the cultivar: all leaves of the cultivar are larger and visually similar in shape to early leaves of the wild subspecies. However, quantitative analysis revealed that leaves of the cultivar are neither geometrically, nor solely allometrically larger versions of early leaves of the progenitor. Leaf shape in the cultivar exhibits novel features as well as effects of allometry shared with the progenitor, hence a simple hypothesis of paedomorphic evolution of leaf shape is not supported.

Grasses of the Precambrian Shield region in eastern lowland Bolivia. II. Life-form and C3–C4 photosynthetic types

ABSTRACTA life-form classification from Neotropical Gramineae is proposed for 113 native species from eastern lowland Bolivia. A factor analysis was performed on a correlation matrix of 51 vegetative attributes to identify ‘character suites,’ which were then used as the basis for the classification. The principal types are arboreal, liana, shrub-like, forb-like, bunch grass with basal foliage, bunch grass with basal and caulescent foliage, caespitose annuals, elongate rhizomes, turf grass, stoloniferous, and decumbent (the last category is further divided into subgroups: -perennial, -indefinite, -floating aquatic, and -vine-like). A key component of the life-form classification is the morphology of leaf blades, with five major patterns recognized: elongate and inrolled, elongate and conduplicate, elongate and flat with an attenuate base, short and broad with an amplexicaule base, and short and broad with a pseudopetiole.The distribution and relative abundance of three major photosynthetic categories were compared with life-form and habitat preference. Photosynthetic type of individual species was identified based on leaf anatomy. C4-(XyMS −) species predominated in cerradao, cerrado, campo rupestre, valleyside campos, and seasonally inundated savanna, as well as on granite outcrops. C4-(XyMS + ) species were relatively rare in all habitats, but were significantly more abundant in the xeric microenvironments of granite outcrops. C3 species predominated in semi-deciduous forest and increased in relative abundance in wetland habitats. Caespitose annuals and bunch grass species were predominantly C4 type, while arboreal and liana species were uniformly C3 type. Grasses classified as decumbent or shrub-like were predominantly C3 type, while rhizomatous, stoloniferous, and forblike grasses were a mixture of C3 and C4 type.The intent of the study was to group morphological characteristics objectively in order to derive a life-form classification specific for the Gramineae. Comparisons of the relative abundance of the various life-forms in a broad range of habitat types provide a descriptive assessment of the adaptive value of these characteristics.

Quinua biosystematics II: Free-living populations

South AmericanChenopodium assignable to sect.Chenopodium subsect.Cellulata (Chenopodiaceae) have been classified on the basis of fruit and leaf blade morphology. Samples representing 99 free-living and domesticated populations were included in a comparative study based on electrophoretic and morphometric data. The resulting patterns of variation indicate that past reliance on the fruit for diagnostic characters has obscured biological relationships. Domesticated and free-living populations of the high Andes, distributed from northwestern Argentina to Colombia, are closely allied and clearly separate from domesticated populations of coastal Chile and free-living populations of Argentina. Circumscription of the ArgentineC. hircinum to include Andean populations is rejected. Specific differentiation among Andean populations, polyphyletic origins forC. quinoa, and the presence of different ploidy levels are not indicated. Free-living Andean types sympatric withC. quinoa are provisionally placed within that species as subsp. milleanum. While the coastal quingua domesticate is clearly distinct from the Andean weed/crop complex, it is provisionally placed within subsp.quinoa to conserve established nomenclature. The overall pattern of morphogenetic variation among South American populations suggests a co-evolutionary relationship between domesticated and free-living populations of the high Andes, with a center of diversity at the southern extreme of the Andean range. Populations ofC. hircinum represent a logical link to the progenitor of the quinua complex, although firm phyletic and systematic alignments will require more information concerning populations of south-central Chile, and further definition of relative affinities among North and South American elements of subsectionCellulata.