Monopodial Growth Research Articles

Impacts of wide row spacings on yield and yield components of upland cotton (Gossypium hirsutum L.)

AbstractThis study quantifies the effects of wide row spacing on lint yield, yield components, and fiber quality of upland cotton (Gossypium hirsutum L.). An experiment was conducted in Tifton, GA in 2021 and 2022, where cotton was planted in six replications of 91‐, 122‐, 152‐, and 183‐cm row spacings. Following defoliation, 1.8 m was hand harvested from each plot, and boll density plant−1 and density ha−1 were determined for sympodial and monopodial branches. Additional measurements included fruit and lint yield distribution assessments and intra‐boll yield components including seed cotton weight boll−1, seed index, seed boll−1, lint weight seed−1, seed surface area (SSA), fiber density, and single fiber weight. Lint yield was reduced 20% in the 183‐cm row spacing compared to the 91‐cm row spacing. The 91‐cm rows had the lowest number of sympodial bolls plant−1 with 152‐ and 183‐cm rows demonstrating a 24%–28% increase in sympodial bolls plant−1. Sympodial bolls ha−1 were reduced 22% in the 183‐cm row spacing compared to the 91‐cm row spacing. There were no differences in bolls ha−1 or lint yield ha−1 with respect to monopodial growth. There were no differences in seed cotton weight boll−1, seeds boll−1, fiber density, single fiber weight, or turnout. Seed index and SSA were increased in the 183‐cm row spacing. Lint weight seed−1 was reduced in the 91‐cm row spacing.

Epistatic interaction between CsCEN and CsSHBY in regulating indeterminate/determinate growth of lateral branch in cucumber

Two genetic loci, det-ma (CsCEN) and det-lb, showed epistatic interaction on indeterminate/determinate growth of LB in cucumber. CsSHBY was identified as the candidate gene for det-lb locus. Plant architecture depends on the spatial regulation of meristems from both main axis (MA) and lateral branches (LBs). Fate (indeterminate or determinate) of these meristems is a crucial source of architectural diversity determining crop productivity and management. CENTRORADIALIS/TERMINAL FLOWER 1/SELF-PRUNING (CETS) gene family have been well known as pivotal regulators for indeterminate/determinate growth of MA. Nevertheless, genes that regulate LB indeterminacy/determinacy remained unclear. Cucumber (Cucumis sativus L.) has typical monopodial growth and multiple lateral branches. Both MA and LBs had indeterminate or determinate growth, and indeterminate/determinate growth of LB was controlled by two distinct loci, det-ma (CsCEN) and det-lb. In our study, based on bulked segregant analysis (BSA) method, the det-lb locus was mapped on a 60.6kb region on chromosome 1 harboring only one gene CsaV3_1G044330, which encoded a putative vacuolar-sorting protein (designated as CsSHBY). Multipoint mutations in CsSHBY were identified in D082 and D226, compared with CCMC, including nonsynonymous SNP mutations and a 6-bp deletion in exons. Further, qPCR showed that CsSHBY was highly expressed in lateral bud of CCMC, suggesting that CsSHBY might play an active role in regulating indeterminate/determinate growth of LB. Genetic analyses showed that det-ma (CsCEN) had an epistatic effect on det-lb (CsSHBY), and CsCEN could activate CsSHBY promoter by Dual luciferase and GUS activity assays. Meanwhile, Cscen or Csshby was found to influence auxin contents and CsYUCs and CsPINs expression levels. These findings provided new insights into precisely optimizing plant architecture for yield improvements.

MULTIPLICACIÓN in vitro DE Phalaenopsis sp. USANDO REGULADORES DE CRECIMIENTO VEGETAL, AGUAMIEL Y PULQUE (COMPLEJOS ORGÁNICOS)

<p><strong>Background:</strong> <em>Phalaenopsis</em> is an orchid of economic importance worldwide. Its natural reproduction is slow due to its monopodial growth (a single apical meristem). Therefore, it is necessary to make <em>in vitro</em> propagation protocols more efficient. <strong>Objectives:</strong> 1. To evaluate three concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) in combination with three of 6-Benzyl Adenine (BA) in the <em>in vitro</em> induction of protocormic like bodies (PLBs) at from leaf explants of <em>Phalaenopsis</em> sp. var. Dudu, under three periods of darkness, 2. To test the effect of four concentrations of honey water and fermented sap, as organic complexes (CO), on the <em>in vitro</em> multiplication rate of PLBs. <strong>Methodology:</strong> Two tests were carried out: Test 1. Three concentrations of 2,4-D (3, 4, 5 mgL<sup>-1</sup>) and three of BA (1, 2, 3 mgL<sup>-1</sup>) were evaluated in leaf explants of <em>Phalaenopsis</em> sp., combined with three periods of darkness 14, 21, 28 days in a completely randomized design with a trifactorial arrangement (27x10). Test 2. Four concentrations of honey water and fermented sap (0, 10, 50, 100 mlL<sup>-1</sup>) were evaluated, arranged in a completely random design (8x10). <strong>Results:</strong> The best combination of plant growth regulators (PGR) for the formation of PLBs (14 PLBs/explant) was with 5 mgL<sup>-1</sup> of 2,4-D and 2 mgL<sup>-1</sup> of BA, during 21 days of darkness. Regarding the use of CO, the addition of 10 mlL<sup>-1</sup> of fermented sap and 50 mlL<sup>-1</sup> of honey water induced the highest rates of multiplication of PLBs/explant (41.4 and 39.6 PLBs). The regeneration of <em>Phalaenopsis</em> sp. from PLBs occurred in 225 days. <strong>Implications:</strong> The results obtained in the two trials are the basis for establishing a protocol for the multiplication of <em>Phalaenopsis</em> sp. <strong>Conclusions:</strong> The combination of 5 mgL<sup>-1</sup> of 2,4-D and 2 mgL<sup>-1</sup> of BA produced the highest number of PLBs/explant (14) at 21 days of darkness and subsequent light exposure for six weeks. On the other hand, the addition of 10 mlL<sup>-1</sup> of fermented sap and 50 mlL<sup>-1</sup> of honey water as CO induced the highest rates of PLBs multiplication (41.4 and 39.6 PLBs, respectively). 100% survival of seedlings was observed after 21 days of acclimatization, under greenhouse conditions.</p>

Solutions to fire and shade: resprouting, growing tall and the origin of Eurasian temperate broadleaved forest.

Tree species of Eurasian broadleaved forest possess two divergent trait syndromes with contrasting patterns of resource allocation adapted to different selection environments: short-stature basal resprouters that divert resources to a bud bank adapted to frequent and severe disturbances such as fire and herbivory, and tall trees that delay reproduction by investing in rapid height growth to escape shading. Drawing on theory developed in savanna ecosystems, we propose a conceptual framework showing that the possession of contrasting trait syndromes is essential for the persistence of broadleaved trees in an open ecosystem that burns. Consistent with this hypothesis, trees of modern Eurasian broadleaved forest bear a suite of traits that are adaptive to surface and crown-fire regimes. We contend that limited opportunities in grassland restricts recruitment to disturbance-free refugia, and en masse establishment creates a wooded environment where shade limits the growth of light-demanding savanna plants. Rapid height growth, which involves investment in structural support and the switch from a multi-stemmed to a monopodial growth form, is adaptive in this shaded environment. Although clustering reduces surface fuel loads, these establishment nuclei are vulnerable to high-intensity crown fires. The lethal effects of canopy fire are avoided by seasonal leaf shedding, and aerial resprouting enhances rapid post-fire recovery of photosynthetic capacity. While these woody formations satisfy the structural definition of forest, their constituents are clearly derived from savanna. Contrasting trait syndromes thus represent the shift from consumer to resource regulation in savanna ecosystems. Consistent with global trends, the diversification of most contemporary broadleaved taxa coincided with the spread of grasslands, a surge in fire activity and a decline in wooded ecosystems in the late Miocene-Pliocene. Recognition that Eurasian broadleaved forest has savanna origins and persists as an alternative state with adjacent grassy ecosystems has far-reaching management implications in accordance with functional rather than structural criteria. Shade is a severe constraint to the regeneration and growth of both woody and herbaceous growth forms in consumer-regulated ecosystems. However, these ecosystems are highly resilient to disturbance, an essential process that maintains diversity especially among the species-rich herbaceous component that is vulnerable to shading when consumer behaviour is altered.

The Valcheta Petrified Forest (Upper Cretaceous), northern Patagonia, Argentina: A geological and paleobotanical survey

The Valcheta Petrified Forest is located in the northeast of the Río Negro Province, Argentina. This work provides a geological characterization of the site and a survey of the fossil logs exposed on the surface and their systematic study. The fossiliferous levels bearing the silicified logs are here referred to the Allen Formation (middle-upper Campanian – lower Maastrichtian, Malargüe Group). These deposits crop out in patches in the study area, and have been deposited on a paleorelief carved in Eopaleozoic rocks of the Nahuel Niyeu Formation being mostly covered by thin layers of Quaternary sediments. The Valcheta Petrified Forest was developed on the margins of a braided fluvial system. Numerous silicified logs have been located at the site. They consist of large axes, not found in life position, with monopodial growth, some of which retain the bases of lateral branches and flared-like base. The estimated height and ages of these trees suggests that it consisted of a mature forest. No other associated vegetative or reproductive structures have been found. Anatomically, a single xylological type has been distinguished and assigned to Podocarpoxylon mazzonii (Petriella) Müller-Stoll et Schultze-Motel, (Podocarpaceae). This taxon has been previously identified from other localities of the Upper Cretaceous to the Danian of Patagonia although never preserved in such complete tree grow architecture. This shows that, along others conifers, cycads and palms, P. mazzonii would have constituted an important element of the arboreal strata in the North Patagonian forest communities during the Campanian–Danian interval producing monotypic patches in some areas.

A Photosynthetic Light Acclimation Model Accounting for the Effects of Leaf Age, Chlorophyll Content, and Intra-Leaf Radiation Transfer.

Mechanistic models of canopy photosynthesis usually upscale leaf photosynthesis to crop level. A detailed prediction of canopy microclimate with accurate leaf morphological and physiological model parameters is the pre-requisite for accurate predictions. It is well established that certain leaf model parameters (Vcmax, Jmax) of the frequently adopted Farquhar and Caemmerer photosynthesis model change with leaf age and light interception history. Previous approaches to predict Vcmax and Jmax focused primarily on light interception, either by cumulative intercepted photosynthetic photon flux density (PPFD) or by closely related proxy variables such as leaf nitrogen content per leaf area. However, for plants with monopodial growth, such as vertically grown tomatoes or cucumber crops, in greenhouse production, there is a strong relationship between leaf age and light interception, complicating the experimental and mathematical separation of both effects. We propose a modeling framework that separates age and light intensity-related acclimation effects in a crop stand: Improved approximation of intra-leaf light absorption profiles with cumulative chlorophyll content (Chl) is the basis, while parameters are estimated via Gaussian process regression from total Chl, carotenoid content (Car), and leaf mass per area (LMA). The model approximates light absorption profiles within a leaf and links them to leaf capacity profiles of photosynthetic electron transport. Published datasets for Spinacia oleracea and Eucalyptus pauciflora were used to parameterize the relationship between light and capacity profiles and to set the curvature parameter of electron transport rate described by a non-rectangular hyperbola on Cucumis sativus. Using the modified capacity and light absorption profile functions, the new model was then able to predict light acclimation in a 2-month period of a fully grown tomato crop. An age-dependent lower limit of the electron transport capacity per unit Chl was essential in order to capture the decline of Vcmax and Jmax over time and space of the investigated tomato crop. We detected that current leaf photosynthetic capacity in tomato is highly affected by intercepted light-sum of 3–5 previous days.

Karakterisasi Anggrek Jenis Phalaenopsis amboenensis J.J. Smith di Wilayah Resort Mallawa Taman Nasional Bantimurung Bulusaraung

Abstract. Resort Mallawa Bantimurung Bulusaraung National Park is a location where many orchids grow. This study aims to determine the type of orchid Phalaenopsis amboenensis J.J. Smith. This study uses the roaming method by conducting a search of the study area and documentation which includes taking pictures and morphological characterization as the basis for identifying orchid species. Orchid exploration was carried out at 4 locations with altitudes ranging from 400 m above sea level to 954 m above sea level. Based on the altitude where the Phaleonopsis amboenensis orchid was found at an altitude of 839 to 927. Based on the light intensity, it was found in semi-shaded conditions with monopodial growth type. Keywords: characterization, bantimurung bulusaraung national park area, phalaenopsis amboenensis j.j. smith, resort mallawa

Кетпен тауындағы Виттрок рауғашының (Rheum wittrockii) биологиялық ерекшеліктері

Мақалада Кетпен тауындағы Виттрок рауғашының (Rheum wittrockii) биологиялық ерекшеліктері туралы мəліметтер келтірілген. Зерттеу мақсаты— Кетпен тауының солтүстік шатқалдарында жəне тау шалғындарының табиғи популяцияларында кездесетін Виттрок рауғашының (Rh. wittrockii) табиғи жағдайдағы биологиялық ерекшеліктерін анықтау. Зерттеу объектісі— Кетпен тауының табиғи популяцияларында кездесетін Виттрок рауғашы (Rh. wittrockii). 2015–2017 жылдың маусым–шілде айларында маршруттық-барлау əдісін қолдана отырып Алматы облысы Ұйғыр ауданына қарасты Кетпен тауының солтүстік шатқалдарында зерттеу жұмыстары жүргізілді. Өсімдік тұқымының морфологиялық ерекшеліктерін анықтау Н.Л. Удольскаяның (1976) əдістемелік нұсқауы бойынша жасалды. Үлкен даму циклындағы өсімдіктердің органдарының құрылымдық өзгеруін систематикалық бақылау, биологиялық eрекшеліктерін, құрылымын анықтау Л.А. Жукованың (2012) инструкциясымен жəне «Программа и методика…» (1986) деп аталатын əдістемелік нұсқаулық бойынша іске асырылды. Кетпен тауында Виттрок рауғашы теңіз деңгейінен (1900–3200 м) биіктіктерде кездесетіндігі анықталды. Өсуінің 1-ші жылында тек вегетативті органдары дамиды. Генеративті өркендердің дамуы өсімдіктің өсуінің2–3-ші жылында басталады. Репродуктивті генеративті өркендердің қарқынды өсуі— вегетативті өркендерінің өсуімен қатар жүреді. Гүлдеу фазасы 7–10 күнге созылады. Бір дарағының гүлдеуі 3–5 күнді құрайды. Генеративті фаза 7–8 (10) жылға дейін созылады. Жемістену процесі шілде айының ортасынан бастап, тамыздың соңғы онкүндігіне дейін жалғасады. Жемістену фазасы 12–14 күн. Өсімдіктің вегетациялық кезеңі 60–75 күнді құрайды. Тұқымы— үшбұрышты жаңғақша. Өскіндердің өсуі жерасты. Өскін— екі нағыз жапырақтан тұрады. Жерасты өркендер жүйесі— көпжылдық өркендердің жерасты жүйесі негізгі жержатаған өркендердің апикальды бүршігі меристемасының белсенділігі есебінен шексіз ұзақ моноподиальды өсудің нəтижесінде пайда болған көпсалалы каудекстен тұрады. Виттрок рауғашының тамыры негізгі, жанама тамырлардан тұрады. Жер асты бөлігінде нəзік жас тамырлары топырақтың беткі горизонтында дамиды. Өскіннен бастап қартайған генеративті кезеңнің ұзақтығы 15–16 жылды құрайды.

DNA barcoding of important fruit tree species of agronomic interest in the genus Garcinia L. from the Western Ghats

Garcinia L. is a pantropically distributed genus with high species richness in South East Asia. It is a tropical evergreen plant with distinct morphological characteristics and has a high degree of endemism. Outstanding features of the Garcinia L. genus are monopodial growth, leafy texture, oil cavities containing yellow or light-colored resins present on all parts of the plant and polygamodioecious reproductive behavior. The current study was conducted to develop barcodes for different species of the genus Garcinia L., distributed widely in the Western Ghats of India. We assess the discrimination power of the plant DNA barcode (rbcL, matK, trnH-psbA, rpoB-trnCGAR and ITS), across major Garcinia L. species. Our results clearly demonstrate the value of plastid barcode data, previously unavailable for Garcinia L. species. Ten Garcinia L. species and three outgroup taxa selected from the Western Ghats of India for evaluation using four regions in the plastid genome (rbcL matK, trnH-psbA, rpoB-trnCGAR) and nuclear-transcribed spacer (nrITS) in order to discriminate them at the species level. A characteristic feature of all barcodes, maximum likelihood analysis, and Wilcoxon signed-rank test were used for species discrimination. The number of conserved sites were more using matK primer whereas more variables and informative sites found in rpoB-trnCGAR loci. For internal branches of species-specific clusters, maximum likelihood analysis showed a more resolved topology. Wilcoxon signed-rank test indicated a higher divergence for coding and non-coding regions. DNA barcoding was found to be a practical and rapid method for identifying more endemic species. These findings will potentially be helpful in delineating the various species of Garcinia L.

The morphostructure of Oxalis incarnata bulbs

The morphostructure of the bulbs of Oxalis incarnata in the conditions of dormancy and the plant’s growth and development are described. The plants were grown in two irrigation modes: 1) with regular irrigation during the year, and 2) with limited irrigation in March-October and without irrigation in November-February. The bulbs were analyzed by way of consequent detaching of the scales. Investigated bulbs always had four fleshy scales, while the number of coriaceous and membranous scales varied. Coriaceous scales, together with two fleshy outer scales, make a protective envelope of the bulb.The overground shoot of O. incarnata, just like in other species of the genus, demonstrates monopodial growth and can produce up to five levels of lateral branches. Elongated parts of overground shoots serve for new territories’ useful occupation, while shortened parts produce new particles. Resting buds (bulbils) of three types were observed in O. incarnata: underground axillary buds, overground axillary gemmae, and terminal gemma. Our investigations showed polyvariance both of organogenesis of the resting buds and ontogenesis of plants in general, depending on irrigation regimes. In the case of limited irrigation, the plants of O. incarnata shed the leaves and can produce terminal gemma. While in the case of regular irrigation during the year, they remain evergreen and form gemmae exclusively in the leaves’ axils. We did not observe the formation of terminal gemmae in the case if axillary gemmae were present.The root system of O. incarnata has a complex structure. It consists of two crowns of the filamentary roots, contractile roots, and additional adventitious roots located along the underground part of the shoot during its growth. Such structure of the root system probably ensures better absorption of the water.

Micropropagation of Camptotheca Acuminata Decne (Nyssaceae) - Endangered Ornamental and Medicinal Tree

Camptotheca acuminata Decne (Nyssaceae) (happy tree, tree of life, cancer tree) is a rapidly growing deciduous and endangered tree endemic to east Tibet and southern China (Liu et al., 2002). C. acuminata is an ornamental tree with monopodial growth, beautiful leaves and shade- and cold- tolerant in their natural environment. Recently, its demand has grown rapidly due to secondary metabolites production like Camptothecin and its derivatives with anti cancer and antivirus activity. The aim of the present study was to develop an efficient protocol for in vitro micropropagation of this valuable plant. Different cultural media based on both MS (Murashige and Skoog, 1962) or DKW (Driver and Kuniyuki, 1984) formulations with different cytokinins (6-benzylaminopurine, BAP or 2-isopentenyladenine, 2iP or meta-topolin, mT) have been involved. The aromatic cytokinin meta-topolin stimulated plant growth. The optimum multiplication rate of Camptotheca shoots occurred on the DKW basal medium, supplemented with 2.5 µM meta-topolin, grown under mixed LED light. The highest number of roots per plantlets was recorded on the rooting medium with 0.3 mgl-1 NAA.

Modification of Architecture of Dwarf Subshrub Thymus seravschanicus (Lamiaceae) in the Republic of Tajikistan

This work describes a life-form of dwarf subshrub Thymus seravshanicus using the architectural approach, which is one of the modern methods for the in-depth study of the plant structure. The species is widely distributed across various ecotopes in the Republic of Tajikistan (Gissar, Zarafshan, and Khazretishi (Hazrati-Shokh) ranges). For the first time, in the structure of individual plants, this study identifies and characterizes an architectural unit (AU) composed of the main compound skeletal axis (n order), compound skeletal axes of the 1st (n + 1) order, branching shoots, and ephemeral shoots. Depending on the position of the main (n order) compound skeletal axis in space, the AU exhibits diversity, including orthotropic, ascending, and mixed types; features of their development have been described. It is shown that, under different ecological and cenotic habitat conditions, the structure of individuals is formed by the multiple repetition of concurrently three or one AUs. In forb steppe (deciduous “black forest” belt) and forb meadow (subalpine belt) communities, the structure of individuals is formed by the combination and multiple repetition of all AUs. On sites with no free substrate available, the development of individuals starts with the formation of an orthotropic AU and a dense shrub is formed; in areas of unoccupied substrate, the development of individuals begins with the formation of an ascending AU and a clump is formed. In the fescue steppe community (juniper belt), the structure of T. seravshanicus individuals is composed only of an ascending AU; a clone is formed. The polyvariance of shoot development is found to be manifested through (1) the intensive branching common for individuals in the conditions of the black forest belt, and the duration of the continued monopodial growth of shoots is up to 3 years; (2) rosette shoots in the conditions of the subalpine belt, and their monopodial growth continues for up to 6 years; and (3) a lack of occurrence of short metamers in the structure of shoots in the conditions of the juniper belt, and the duration of monopodial growth is up to 2 years. The features that were identified are mechanisms of adaptation of T. seravshanicus to growing conditions and do not lead to changes in the life-form of the dwarf subshrub. These findings expand the understanding of the dwarf subshrub structure and their morphological plasticity and provide a basis for modeling the ways dwarf subshrubs morphologically transform of in different habitats.

Architecture of the Dwarf Shrub Thymus petraeus (Lamiaceae) in the Conditions of Southern Siberia

The structure of Thymus petraeus individuals has been studied architecturally. It has been established that in the south of Siberia the species occurs in similar habitats: in true, meadow, sandy steppes and their petrophytic variants on the slopes and low rocky peaks of hills. According to the classification proposed by I.G. Serebryakov (1964), T. petraeus is a vegetatively semimobile dwarf shrub with a system of the main root that is persistent throughout its life and with rooting runners. Three architectural units that differ in the spatial position of the compound skeletal axis (orthotropic–plagiotropic, plagiotropic, and orthotropic) have been identified in the structure of T. petraeus individuals. Each architectural unit consists of the main compound skeletal axis, compound skeletal axes of the 1st order, formation shoots, branching shoots, and enrichment shoots. It is shown that the structure of individuals can be formed by repeating only two architectural units. It is established that the structure of individuals growing in the true steppes and their petrophytic variants is built at the expense of the repetition of orthotropic–plagiotropic and plagiotropic architectural units. That in sandy steppes is built at the expense of repetition of plagiotropic and orthotropic architectural units. The features of T. petraeus development in specific ecological and coenotic conditions are shown. In this regard, we have characterized (1) morphological polyvariance, which is based on changes in the structure of shoots (shortened and elongated) and the composition of architectural units (no compound skeletal axes of the 1st order or enrichment shoots); (2) dimensional polyvariance, manifested in a change in the length and number of compound skeletal axes; and (3) dynamic polyvariance, associated with fluctuations in the duration of the monopodial growth of shoots formation (from 2 to 5 years) and the architectural unit as a whole (from 6 to 20 years). The revealed modifications of architecture do not lead to a change in the life form of the dwarf shrub, but reflect the mechanisms of its adaptation.

Epidendrum bermejoense (Orchidaceae), especie nueva del noroeste de la Argentina y sur de Bolivia

Se describe e ilustra Epidendrum bermejoense (Orchidaceae, Epidendreae, Laelii- nae) del noroeste de la Argentina y del sur de Bolivia. El taxón nuevo es una hierba de crecimiento monopodial, inflorescencia arqueada y pauciflora, flores con el lóbulo medio bien dividido en un par de lóbulos divergentes falcados a lanceolados y más anchos que los lóbulos laterales. Se asemeja a un grupo de especies caracterizadas por poseer tallos cilíndricos con nudos conspicuos, pétalos frecuentemente más angostos que los sépalos, con el lóbulo medio bilobado y polinias generalmente comprimidas y en forma de ala de pájaro. Se incluye una clave para diferenciarlo de: E. lindbergii Rchb. f., E. andres-johnsonii Hágsater & E. Santiago, E. densiflorum Hook. y E. hassleri Cogn., todas pertenecientes al grupo Pseudoepidendrum subgrupo Densiflorum. Con este trabajo se aporta una entidad más al conocimiento de la flora del noroeste de la Argentina y sur de Bolivia.

Morphological Adaptation of Thymus (Lamiaceae) Species in Yakutia

The variety of life forms and the structure of individuals and ontomorphogenesis of T. extremus, T. indigirkensis, T. brevipetiolatus, and T. pavlovii under the conditions of Yakutia have been studied. It has been established that the formation of two life forms and three types of biomorphs is characteristic for the species: a monocentric vegetatively immobile dwarf subshrub (T. extremus), an implicitly polycentric vegetatively semimobile dwarf subshrub and dwarf shrub (T. indigirkensis and T. brevipetiolatus respectively), and an obviously polycentric vegetatively mobile dwarf subshrub (T. pavlovii). The basis of the adult shrub is a monopodially sympodially growing compound skeletal axis which differs in individuals of Thymus by the method of growth and position in space. An analysis of the development of species in Yakutia allowed us to identify common and specific features. Common features for the species are the predominance of the dwarf subshrub living form and its morphological plasticity, a small variety and shortening of the morphogenesis phases, a shallow rejuvenation of the ramets, a prolonged monopodial growth of shoots (up to 10 years), and the predominance of rosette shoots in the structure of the individual. Differences are revealed depending on the conditions of specific habitats of species. When T. extremus grows on a flat surface and high sludge, a dense primary shrub is formed. In the free areas of the substrate with stepwise depressions of the microrelief, the primary shrub T. extremus is loose. In T. brevipetiolatus, which grows in the steppe on the hillside, the structure of the individual is formed only by rosette shoots, their prolonged monopodial growth is maintained due to the preservation (for 1–2 years) of dry leaves. For T. pavlovii growing on a mossy substrate, this is the characteristic lodging of shoots, their intensive rooting and strengthening of vegetative mobility, and a reduction in the duration of ontogenesis of individuals due to the rapid decay of maternal structures. The revealed features of Thymus development are the mechanisms of morphological adaptation, which provide species survival in different environmental conditions of Yakutia.

EPICORMIC SHOOTS INDUCTION AND ROOTING CUTTINGS OF Calophyllum brasiliense

ABSTRACT Calophyllum brasiliense is present in a wide natural distribution range in Brazil and its monopodial growth, with a rectilinear stem and a moderately dense timber has attracted the attention from the logging industry in recent decades. In the meantime, the lack of efficient rescue and vegetative propagation methods of adult plants has been a narrowing condition for the selection of superior genotypes in breeding programs of the species. Therefore, we evaluate epicormic shoots induction methods and the rooting cuttings of 14 year-old Calophyllum brasiliense trees. From this scope, three methods of epicormic shoots induction were evaluated: coppicing, girdling and partial girdling. We evaluate the number of produced sprouts and the percentage of sprouted trees at 06, 12 and 15 months’ after the experiment installation. Results have indicated the feasibility of Calophyllum brasiliense vegetative rescue by cuttings method using epicormic shoots induced by coppicing and girdling. In contrast, partial girdling was not effective in epicormic shoots emission. Concerning adventitious roots, the sprouting technique had no influence in the rooting of cuttings, showing variation among the different stock plants.

Mechanical Harvesting and Postharvest Storage of Two Southern Highbush Blueberry Cultivars Grafted onto Vaccinium arboreum Rootstocks

The profitability of the fresh market blueberry industry in many areas is constrained by the extensive use and cost of soil amendments, high labor requirements for hand harvesting, and the inefficiencies of mechanical harvesters. Vaccinium arboreum Marsh is a wild species that has wide soil adaptation and monopodial growth habit. It has the potential to be used as a blueberry rootstock, expanding blueberry production to marginal soil and improving the mechanical harvesting efficiency of cultivated blueberry. The objectives of this research were to compare yield, berry quality, and postharvest fruit storage of own-rooted vs. grafted southern highbush blueberry (SHB) cultivars (Farthing and Meadowlark) grown on amended vs. nonamended soil and either hand or mechanical harvested. Yields of hand-harvested SHB during the first two fruiting years were generally greater in own-rooted plants grown on amended soil compared with own-rooted plants on nonamended soil or grafted plants on either soil treatment. However, by the second fruiting year, hand-harvest yields of grafted SHB were ≈80% greater than own-rooted plants when grown in nonamended soil. Yields of mechanical-harvested SHB grafted on V. arboreum and grown in either soil treatment were similar to yields of mechanical-harvested own-rooted plants in amended soil the second fruiting year, and greater than yields of own-rooted plants in non-amended soil. In general, mechanical harvesting reduced marketable yield ≈40% compared with hand harvesting. However, grafted plants reduced ground losses during harvest by ≈35% compared with own-rooted plants for both cultivars. Mechanical-harvested berries had a greater total soluble solids:total titratable acidity ratio (TSS:TTA) than hand-harvested berries, and berries harvested toward the end of the harvest season had a greater TSS:TTA than those from early-season harvests. As postharvest storage time increased, berry appearance ratings decreased and berry softness and shriveling increased, particularly in mechanical-harvested compared with hand-harvested berries. Firmness of mechanical-harvested berries decreased during storage, whereas firmness of hand-harvested berries remained relatively stable. However, fruit quality at harvest and during postharvest storage was unaffected by V. arboreum rootstocks or lack of pine bark amendment. This study suggests that using V. arboreum as a rootstock in an alternative blueberry production system has the potential to decrease the use of soil amendments and increase mechanical harvesting efficiency.

Morphological structure of inflorescences of Agastache breviflora (A. Gray) Epling, A. rugosa (Fisch. & C.A. Mey.) Kuntze, and A. rupestris (Greene) Standl. (family Lamiaceae) ex situ

The results of comparative analysis of morphological structure of inflorescences Agastache breviflora, A. rugosa, and A. rupestris introduced in the O.V. Fomin Botanical Garden are represented. It has been established that the common morphological characteristics for inflorescences of these plants are: the type of inflorescence (thyrs), its location on the shoot (terminal), type of the growth of main and lateral axes (monopodial growth of the main axis and sympodial growth of lateral axes on which are formed the partial inflorescences – cymoids), the structure of the partial inflorescences (system of dichasia). Differences are determined by the linear dimensions of inflorescences, quantity and size of flowers in partial inflorescences, orientation of the main axis and flowers in space, presence or absence of bracts and bracteoles.

Factors affecting the stemflow of trees in the Brazilian Cerrado

AbstractStemflow is a hydrological flux that largely influences the input of rainwater to the soil and its spatial distribution. Here, we aimed to identify the factors influencing this hydrological flux by quantifying the stemflow of 129 trees in the Brazilian savannah. The attributes of individual trees were investigated as predictor variables influencing either stemflow volume or tree efficiency in generating stemflow—proportion of rainfall over the canopy flowing down the stem. The volume of stemflow was higher in trees that were large, had perennial leaves, and exhibited monopodial growth. However, the efficiency of a tree in generating stemflow was negatively correlated to its dimensions. The most efficient trees had a smooth bark surface, monopodial growth, and straight stems. There was large variation in efficiency among individuals, which is related to the high diversity of attributes among the studied trees. The small size of Cerrado trees explains the lower stemflow volume in comparison with trees in forest ecosystems. The efficiency observed in the Cerrado trees was also lower when compared to trees from other ecosystems, even in arid environments. Copyright © 2014 John Wiley & Sons, Ltd.

Campanula teutana, a new isophyllous Campanula (Campanulaceae) from the Adriatic region

The Balkan Peninsula and the amphi-Adriatic region are biodiversity centres with a high number of Campanula species, some of them with restricted and isolated distributions. Among those is the morphologically, karyologically and genetically well-defined linage of isophyllous Campanula species of the garganica clade, taxonomically treated as Campanula ser. Garganicae. In the central Adriatic, on the Island of Vis (Croatia), an isophyllous Campanula was found growing in rocky crevices of calcareous sea cliffs among chasmophytic vegetation with extremely challenging ecological conditions. Based on morphological characters (monopodial growth form, cordate to ovate basal leaves, campanulate corolla, presence of obtuse hairs at the base of filaments, capsule opening by basal pores and brown shiny seeds) the unidentified plant from the Island of Vis falls into ser. Garganicae. To establish the phylogenetic position and relationships of the unknown Campanula among other species of the garganica clade, nuclear ITS and chloroplast trnL-F sequences as well as comparative morphology, karyology and scanning electron microscopy of seeds were used. Due to its campanulate corolla the plants from Vis are morphologically close to C. portenschlagiana from the eastern Adriatic, from which they differ in several quantitative floral characters. The karyological analysis revealed a diploid chromosome number (2n = 34), while SEM analysis showed that seed coat of new taxon has weakly striate testa, thin wavy striped radial walls and slightly marked lumen. Additionally, molecular data show that the Vis taxon is clearly separated as a distinct species from other species of ser. Garganicae. Therefore, it is described and illustrated as a new species, Campanula teutana Bogdanović & Brullo. Because of the small number of individuals within the single population, C. teutana should be included on the Red List of the vascular flora of Croatia as an endangered species (EN).