Structure and development of shoots in Cytisus scoparius

1990 ◽  
Vol 68 (12) ◽  
pp. 2576-2582 ◽  
Author(s):  
Tian Su Zhou ◽  
Noboru Hara
Keyword(s):  
Growing Season ◽  
Lateral Branch ◽  
Main Axis ◽  
Leaf Primordia ◽  
Axillary Meristem ◽  
Cytisus Scoparius ◽  
Lateral Branches ◽  
Winter Buds ◽  
The Relationship ◽  
Characteristic Manner

The vegetative winter bud of Cytisus scoparius Link contains about nine leaf primordia. It grows into a main axis during the current growing season. At the end of the growing season, a shoot system consisting of a main axis and many lateral branches is formed. The lateral branch originates as a primordium when winter buds expand in spring, from the axil between the sixth and eighth leaves (numbered from the base of the bud), following which the succeeding primordia of branches appear sequentially. These lateral primordia continue to extend synchronously with the extension of the main axis during the growing season. By the end of the growing season, the lateral branches have reached various lengths and are arranged in a somewhat characteristic manner on the main axis; the relatively long branches are often located on the portions with ternately compound leaves and are associated with the vigorous elongation of the main axis. The relationship between the growth of the lateral branches and the main axis is discussed. Key words: axillary meristem, Cytisus, proleptic shoot, sylleptic shoot.

Cone initiation and development before dormancy in yellow cedar (Chamaecyparis nootkatensis)

1974 ◽  
Vol 52 (9) ◽  
pp. 2075-2084 ◽  
Author(s):  
John N. Owens ◽  
Marje Molder
Keyword(s):  
Mitotic Activity ◽  
Lateral Branch ◽  
Leaf Primordia ◽  
Day Length ◽  
Chamaecyparis Nootkatensis ◽  
Seed Cone ◽  
Cone Development ◽  
Cone Apex ◽  
Lateral Branches ◽  
Pollen Cone

Vegetative shoots initiate leaves and lateral branches continuously from mid-April until the end of September. No buds with bud scales are formed and the vegetative apex is enclosed by leaf primordia at various stages of development. Pollen cones are initiated on proximal vegetative shoots during a 3-week period from mid-June to early in July. Transition to a pollen-cone apex is marked by an increase in mitotic activity in the apex and by the formation of a lateral branch in the axil of one of the last-formed leaf primordia, causing the apex to appear to branch dichotomously. The lateral branch remains at the base of the pollen cone and may resume growth the next year after the pollen cone is shed. Pollen-cone development continues until the end of September. Meiosis occurs during the last 2 weeks of August, and pollen develops during September. Seed cones are initiated on newly formed, distal axillary vegetative shoots during a 3-week period from late June to mid-July. Transition to a seed-cone apex is marked by an increase in mitotic activity followed by bract-scale initiation. Usually three ovules are initiated in the axil of each bract scale. Seed-cone development is complete by early September and the seed cones become dormant. The pattern of reproduction in yellow cedar is compared to other conifers and the possible relationships are discussed between time of cone initiation, sexuality of cones, and day length.

New occurrences of trimerophytes from the Devonian of eastern Canada

1978 ◽  
Vol 56 (24) ◽  
pp. 3052-3068 ◽  
Author(s):  
Jeffrey B. Doran ◽  
Patricia G. Gensel ◽  
Henry N. Andrews
Keyword(s):  
Middle Devonian ◽  
Early Stage ◽  
Lateral Branch ◽  
Main Axis ◽  
Eastern Canada ◽  
Morphologic Variation ◽  
Lateral Branches ◽  
Branch Type ◽  
Established Species ◽  
New Occurrences

Pertica dalhousii n.sp. is described from the late Lower or early Middle Devonian of New Brunswick. The plant is known from a central axis with spirally arranged, mostly dichotomous lateral branches. Some lateral branches terminate in erect clusters of 32–128 fusiform sporangia. Spores are circular, trilete, with a detachable outer sculptured layer, and resemble the dispersed spore genus Apiculiretusispora Streel. A trimerophyte from Gaspé is described and provisionally designated as cf. Pertica sp.; the specimens are too incompletely preserved to be assigned to any established species, but they add further information about morphologic variation in the genus Pertica.With the addition of new plant types referable to the trimerophytes, distinctions between genera and species are becoming less readily apparent, supporting the suggestion that the trimerophytes are a group of closely related plants in which considerable evolution was occurring in late Lower and Middle Devonian times. Additionally, these plants appear to represent an early stage in the differentiation of a distinct main axis – lateral branch type of organizaiton that probably led to the later evolution of megaphyllous leaves.

scholarly journals Indices of tree competition in dense spruces stand originated from natural regeneration

2013 ◽  
Vol 59 (3) ◽  
Author(s):  
Vladimír Šebeň ◽  
Michal Bošeľa ◽  
Bohdan Konôpka ◽  
Jozef Pajtí
Keyword(s):  
Natural Regeneration ◽  
Tree Height ◽  
Lateral Branch ◽  
Experimental Site ◽  
Competition Intensity ◽  
Stem Base ◽  
Biometric Parameters ◽  
Spruce Stands ◽  
Lateral Branches ◽  
The Relationship

AbstractThis paper aims to quantify relationships between the biometric parameters of young, 15-year old spruce stands at the Experimental Site Vrchslatina. In 2011, 40 spruce trees were selected to cover four classes of bio-sociological status (dominant, co-dominant, sub-dominant, and suppressed - 10 individuals each). The trees were measured for their height increments (by recording the distances between the successive whorls) and the increments of lateral branches at all whorls. The sample trees were then cut down and discs were taken from the stem base. In the laboratory, the discs were measured for the annual ring widths using WinDendro software. We focused on detailed analyses of the relationship between the bio-sociological status of the trees on the radial and height increments. Minor differences were found in the increments in the newest lateral whorls. The ratio between height increments and lateral branch increments was found to be higher in dominant trees (height increments is two times higher than the increments on the lateral branches). Conversely, the smallest ratio was found in suppressed trees (the ratio was around 1). The ratio between tree height and diameter at the stem base, as well as the ratio between height and radial increments, was the smallest for dominant and the highest for suppressed trees. Hence, relationships between height and diameter increments (both annual and cumulative) proved to reflect competition intensity among trees.

scholarly journals Growth, fructification and plastochron index of different branches in the crown of the husk tomato (Physalis ixocarpa Brot.)

2014 ◽  
Vol 54 (3) ◽  
pp. 195-206 ◽  
Author(s):  
Juan M. Brito ◽  
Leszek S. Jankiewicz ◽  
Victor M. Orduna ◽  
Francisco C. Escobar ◽  
Luis M. Covarrubias
Keyword(s):  
Lateral Branch ◽  
Main Axis ◽  
Flower Bud ◽  
Vegetative Period ◽  
Short Period ◽  
Plant Produce ◽  
Lateral Branches ◽  
Sympodial Growth ◽  
Plastochron Index ◽  
Husk Tomato

The husk tomato (<em>Physalis ixocarpa</em> Brot.) is commonly cultivated in Central Mexico for its fruits. The plants of cv. 'Rendidora' show sympodial growth after forming 3-5 internodes in the main axis. From there on, each internode is terminated with a node having one flower bud, one leaf and 2 branches (dichasium type of branching). With the exclusion of the first 3 bifurcations which initiate 4 equal apparent main branches of the plant, each subsequent bifurcation has unequal ramifications: a stronger one which prolongs the apparent main branch, and a weaker one which serves as the origin of an apparent lateral branch. The apparent lateral branches form smaller internodes but these internodes require more time for their growth which is the reason that the plastochron lasts longer in the apparent lateral branches. By forming a smaller number of internodes in the same period of time, the apparent lateral branches reach a lower value of the plastochron index. All apparent lateral branches of a plant produce a greater total number of fruits, but a large proportion of them abscise. Due to this, the harvested fruits come principally from the apparent main branches. The phenology of the husk tomato plant is described. Its short period of development makes possible its cultivation in regions with a limited vegetative period.

scholarly journals THE RELATIONSHIP BETWEEN MORPHOLOGICAL TRAITS AND SEED YIELD OF IRANIAN GARDEN CRESS ACCESSIONS

2019 ◽  
Vol 18 (3) ◽  
Author(s):  
Vahid Rahimi ◽  
Mehdi Mohebodini ◽  
Mahdi Behnamian ◽  
Shiva Azizinia
Keyword(s):  
Seed Yield ◽  
Yield Components ◽  
Seed Weight ◽  
Main Axis ◽  
Phenotypic Correlation ◽  
Garden Cress ◽  
Lateral Branches ◽  
The Relationship ◽  
Thousand Seed Weight ◽  
Number Of Seeds

In order to evaluate the relationship between traits affecting the seed yield of the garden cress, phenotypic correlations between seed yield and yield components were detected, direct and indirect effects of yield components on yield and its role in the description of diversity were estimated, and the experiment was conducted in a randomized complete block design with three replications in 2017. The ANOVA showed that the difference among accessions was significant for all traits. There was a significant phenotypic correlation between yield and most of the traits. The highest value of phenotypic correlation was obtained between seed yield and the ‘thousand seed weight’ (0.97). The regression analysis showed that the seed yield was highly in- fluenced by the ‘thousand seed weight’, leaf height and the number of seeds per silique of the lateral branches and the main axis. These three traits constituted about 89% of changes in the total yield, while the ‘thousand seed weight’ was the most effective trait that entered the model and explained 51% of the variation. The path analysis of phenotypic correlation showed that the ‘thousand seed weight’ had the greatest direct effect on the yield (7.21). The ‘thousand seed weight’ had a positive indirect impact on other traits as well. As a result of the factor analysis, 3 independent factors explained about 79.33% of the yield variation. These factors con- sisted of the number of seeds per silique of the lateral branches, the number of seeds per silique of the main axis and the ‘thousand seed weight’.

Barley seed storage under controlled conditions

2019 ◽  
pp. 140-150 ◽  
Author(s):  
O. A. Zadorozhna ◽  
T. P. Shyianova ◽  
M.Yu. Skorokhodov
Keyword(s):  
Hordeum Vulgare ◽  
Moisture Content ◽  
Spring Barley ◽  
Seed Storage ◽  
Growing Season ◽  
Storage Conditions ◽  
Meteorological Conditions ◽  
Hordeum Vulgare L ◽  
The Relationship ◽  
And Storage

Seed longevity of 76 spring barley gene pool samples (Hordeum vulgare L. subsp. distichon, convar. distichon: 56 nutans Schubl., two deficience (Steud.) Koern., two erectum Rode ex Shuebl., two medicum Koern.; convar. nudum (L.) A.Trof.: one nudum L. та subsp. vulgare: convar. vulgare: nine pallidum Ser., three rikotense Regel.; convar. coeleste (L.) A.Trof.: one coeleste (L.) A.Trof.) from 26 countries, 11 years and four places of reproduction was analyzed. Seeds with 5–8% moisture content were stored in chamber with unregulated and 4oC temperature. The possibility of seed storage under these conditions for at least 10 years without significant changes in germination has been established. The importance of meteorological conditions in the formation and ripening of seeds for their longevity is confirmed. The relationship between the decrease of barley seeds longevity and storage conditions, amount of rainfall, temperature regime during the growing season of plants is discussed.

Phyllotaxis of the palm Euterpe oleracea Mart. at the level of the shoot apical meristem

Botany ◽  
2010 ◽  
Vol 88 (5) ◽  
pp. 528-536 ◽  
Author(s):  
Denis Barabé ◽  
Laura Bourque ◽  
Xiaofeng Yin ◽  
Christian Lacroix
Keyword(s):  
Shoot Apical Meristem ◽  
Fundamental Theorem ◽  
Apical Meristem ◽  
Leaf Primordia ◽  
Leaf Primordium ◽  
Divergence Angle ◽  
Euterpe Oleracea ◽  
The Mean ◽  
The Relationship ◽  
Euterpe Oleracea Mart

Previous studies on palm phyllotaxis deal mainly with the mature trunk. The goals of this study are (i) to determine the relationship between the number of parastichies, the divergence angle, and the plastochrone ratio at the level of the shoot apical meristem; (ii) to examine whether there are fluctuations in the divergence angle; (iii) to interpret the significance of phyllotactic parameters with respect to the mode of growth of the apex. The tubular base of the leaf primordium is more or less asymmetrical, and completely surrounds the shoot apical meristem. The phyllotactic system corresponds to a (2, 3) conspicuous parastichy pair. The mean divergence angle per apex varies between 126.9° ± 9.3° (mean ± SD) and 135. 8° ± 8.0°. Divergence angles for all apices fluctuate within a range of 115.89° to 157.33°. The mean plastochrone ratios between apices varies from 1.35 ± 0.18 to 1.58 ± 0.12. The plastochrone ratio at each plastochrone for all apices ranges from 1.09 to 2.00. There is no correlation between the angle of divergence and the plastochrone ratio. There is a fluctuation in the value of the divergence angle that falls within the range predicted by the fundamental theorem of phyllotaxis. The high value of the ratio of the diameter of leaf primordia over the diameter of the apex, and the long plastochrone might explain the lack of correlation between certain phyllotactic parameters.

scholarly journals Relations among Valencia orange yields with soil and leaf nutrients in Northwestern Paraná, Brazil

2000 ◽  
Vol 43 (4) ◽  
pp. 387-391 ◽  
Author(s):  
Jonez Fidalski ◽  
Pedro Antonio Martins Auler ◽  
Valdomiro Tormem
Keyword(s):  
Growing Season ◽  
Fruit Weight ◽  
Soil Samples ◽  
Low Fertility ◽  
High Productivity ◽  
Leaf Nutrients ◽  
Valencia Orange ◽  
Northwest Region ◽  
The Relationship ◽  
K Fertilization

The Valencia orange orchards established on soils of low fertility in the Northwest region of Paraná State, Brazil, have showed symptoms of Mg deficiency and reduced fruit yields. The objective of this study was to verify the relationship between yield with soil and leaf nutrients during 1996/97 growing season. Two sites of low and high productivity were selected in seven orchards. Leaf and soil samples (fertilized rows and interrows) were collected in 1996. The results showed that the citrus yields were negatively related with soil Mg/K and Ca+Mg/K ratios in the fertilized rows, and fruit weight positively correlated with leaf Zn in the low productivity orchards. The fruit weight was positively related with leaf Ca and soil Ca in the fertilized rows of the high productivity orchards. The results suggested an adequate lime and K fertilization managements in the fertilized rows, as well as an adequate Zn supply.

scholarly journals Peculiarly pleasant weather for US maize

2018 ◽  
Vol 115 (47) ◽  
pp. 11935-11940 ◽  
Author(s):  
Ethan E. Butler ◽  
Nathaniel D. Mueller ◽  
Peter Huybers
Keyword(s):  
Climate Change ◽  
Growing Season ◽  
Crop Model ◽  
World Population ◽  
Growth Phases ◽  
Climate Trends ◽  
Historical Trends ◽  
Yield Trends ◽  
The Relationship ◽  
Temperature Responses

Continuation of historical trends in crop yield are critical to meeting the demands of a growing and more affluent world population. Climate change may compromise our ability to meet these demands, but estimates vary widely, highlighting the importance of understanding historical interactions between yield and climate trends. The relationship between temperature and yield is nuanced, involving differential yield outcomes to warm (9−29 °C) and hot (>29 °C) temperatures and differing sensitivity across growth phases. Here, we use a crop model that resolves temperature responses according to magnitude and growth phase to show that US maize has benefited from weather shifts since 1981. Improvements are related to lengthening of the growing season and cooling of the hottest temperatures. Furthermore, current farmer cropping schedules are more beneficial in the climate of the last decade than they would have been in earlier decades, indicating statistically significant adaptation to a changing climate of 13 kg·ha−1· decade−1. All together, the better weather experienced by US maize accounts for 28% of the yield trends since 1981. Sustaining positive trends in yield depends on whether improvements in agricultural climate continue and the degree to which farmers adapt to future climates.

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