scholarly journals Developmental differences in rice plants in relation to photoperiodism.

1953 ◽  
Vol 1 (3) ◽  
pp. 202-216
Author(s):  
C. Coolhaas ◽  
Th.M. Wormer
Keyword(s):  
Subsequent Development ◽  
Morphological Characters ◽  
Developmental Differences ◽  
Reproductive Stage ◽  
Main Stem ◽  
Axillary Buds ◽  
Direct Influence ◽  
Rice Plants ◽  
Growing Period ◽  
Stages Of Growth

Two varieties of rice sensitive to the length of photoperiod, Nero di Vialone and Kameji, and 2 insensitive varieties, Fortuna and Karang Serang, were subjected to daily photoperiods of 12 and 18 hr. applied either throughout the growing period or at various stages of the growing period. Earlier formation of panicles was induced by 12 hr. than by 18 hr. photoperiods in the case of Nero di Vialone and Kameji, but not in the case of Fortuna and Karang Serang. Where early flowering was induced by the use of 12 hr. photoperiods the panicles on the main stem were smaller than corresponding panicles on plants grown with 18 hr. photoperiods. The length of photoperiod had no direct influence on the growth of leaves. In the case of the sensitive variety Nero di Vialone, all tillers subjected to 12 hr. photoperiods from the beginning of growth entered the reproductive stage, after which a proportion of them ceased development, whereas a proportion of the tillers subjected to 18 hr. photoperiods from the beginning of growth ceased development before they had formed an inflorescence. A change from 12 hr. to 18 hr. photoperiods in sensitive varieties at the time of initiation of inflorescences caused a delay, and a change from 18 hr. to 12 hr. photoperiods, a hastening, of the subsequent development of flowers. The morphological characters of the axillary buds of rice plants at various stages of growth are described.-W.J.B. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Desempenho morfofisiológico de cultivares de soja de ciclo médio em condições de alagamento do solo

2017 ◽  
Vol 12 (3) ◽  
pp. 385
Author(s):  
Marcos Paulo Ludwig ◽  
Sandro De Oliveira ◽  
Luis Osmar Braga Schuch ◽  
Francisco Jesus Vernetti Junior ◽  
Rogério Seus ◽  
...  
Keyword(s):  
Plant Height ◽  
Reproductive Stage ◽  
Main Stem ◽  
Vegetative Stage ◽  
Cultivation Condition ◽  
Soil Flooding ◽  
Soybean Cultivars ◽  
Content Index ◽  
Crop Cycle ◽  
Stem Chlorophyll

<p>O aumento no cultivo de soja no Brasil têm atingido áreas antes utilizadas para outros fins, como em regiões de solos de várzea, estando assim, sujeita a eventuais alagamentos do solo. Este trabalho objetivou avaliar alterações morfofisiológicas em cultivares de soja de ciclo médio, em condições de alagamento do solo, nos estádios fenológicos vegetativo e reprodutivo para recomendação de cultivares. Os experimentos foram conduzidos na Estação Experimental de Terras Baixas, da Embrapa Clima Temperado em Capão do Leão, RS. Foram aplicados três sistemas de manejo da água: condição normal de cultivo (sem alagamento), alagamento no período vegetativo (V3/V4) e alagamento no período reprodutivo (R2/R3). As avaliações realizadas durante o ciclo da cultura foram: altura de plantas, diâmetro da haste principal, índice do teor de clorofila, fenologia e número de nós nas hastes por planta. O alagamento do solo reduz o número de nós na haste principal, reduzindo a estatura das plantas, sendo os efeitos mais acentuados quando o alagamento ocorre no estádio vegetativo. Além disso, o alagamento do solo no período reprodutivo promove aumento do diâmetro da haste principal. O alagamento do solo causa retardamento de ocorrência dos estádios fenológicos, bem como do ciclo total das cultivares de soja.</p><p align="center"><strong><em>Morphophysiological performance of medium cycle soybean cultivars under flooding</em></strong><strong><em></em></strong></p><pre><strong>Abstract: </strong>The increase in soybean cultivation in Brazil has reached areas previously used for other purposes, such as in regions of lowland soils, thus being subject to possible soil flooding. This study aimed to evaluate morphophysiological changes in medium cycle soybean cultivars, under soil flooding conditions, in the vegetative and reproductive stages to recommend cultivars.<strong> </strong>The experiments were conducted at the Estação Experimental de Terras Baixas, EMBRAPA Clima Temperado in the Capão do Leão city, RS. Three water management systems were applied: normal cultivation condition (without flooding), flooding in the vegetative stage (V3 / V4) and flooding during the reproductive stage (R2 / R3). During the crop cycle, plant height, diameter of the main stem, chlorophyll content index, phenology and number of nodes in the stem per plant were collected. On the basis of the results this study, it can be concluded that he flooding reduces the number of nodes on the main stem, reducing plant height, with the most pronounced effects when flooding occurs in the vegetative stage. Furthermore, flooding the reproductive stage promotes increased diameter of the main stem. Flooding causes delay of occurrence of phenological stages and the total cycle of soybean cultivars.</pre>

scholarly journals The effect of the photoperiod on the level of endogenous growth regulators in pine (Pinus silvestris L.) seedlings

2014 ◽  
Vol 51 (1) ◽  
pp. 59-70 ◽  
Author(s):  
Krystyna Kriesel ◽  
Sławomir Ciesielska
Keyword(s):  
Abscisic Acid ◽  
Growth And Development ◽  
Morphological Characters ◽  
Axillary Buds ◽  
Pinus Silvestris ◽  
Low Intensity ◽  
Pine Seedlings ◽  
Terminal Bud ◽  
Development Processes ◽  
High Level

The investigations were performed on pine seedlings growing under 12, 16 and 20 hour photoperiods. In 4 succesive stages of seedling development i.e. after 2, 12, 18 and 30 weeks of culture morphological characters of the seedlings were measured and the levels of auxins-, gibberellins-, cytokininsand abscisic acid-like inhibitor were determined. The intensity of growth and development of juvenile leaves, needles and of the shoot was the lowest in plants growing under 12 hour photoperiod conditions. As the length of the photoperiod increased so did the intensity of these processes. Under the 12 hour photoperiod the development of scale leaves, axillary buds and the formation of the terminal bud started earliest. This process reached completion under the 12 hour photoperiod and the bud remained in a state of dormancy. Seedlings growing under the 12 hour photoperiod were characterized by a low level of stimulators, and at the same time by a high level of inhibitors. On the other hand in seedlings grown at 16 and 20 hour photoperiods the content of stimulators was higher and that of inhibitors lower. A high intensity of growth and development processes was correlated with a high level of stimulators while a high level of inhibitors was correlated with a low intensity of these processes.The obtained results suggest the participation of gibberellins and cytokinins in the processes of regulation of the initiation of scale leaves and axillary buds, and the participation of these hormones and of abscisic acid in the regulation of needle elongation.

Effects of defoliation intensity at the first grazing of forage rape (Brassica napus L.) by dairy cattle on subsequent regrowth potential, total DM consumed, nutritive characteristics and nutrient selection

2013 ◽  
Vol 53 (3) ◽  
pp. 226 ◽  
Author(s):  
G. N. Ward ◽  
J. L. Jacobs
Keyword(s):  
Brassica Napus ◽  
High Intensity ◽  
Present Experiment ◽  
Moisture Stress ◽  
Crop Growth ◽  
Water Soluble ◽  
Axillary Buds ◽  
Forage Crops ◽  
Brassica Napus L ◽  
Growing Period

The use of summer brassica forage crops in dryland dairy systems in southern Victoria is considered a key component of the feed base as they provide home-grown forage with high nutritive characteristics during a period where perennial ryegrass growth is limited due to high summer temperatures and low soil water content. Current knowledge on the use of single-grazing brassica crops such as turnips (Brassica rapa L.) is well defined; however, information on the management of regrowth brassica species that can provide multiple grazings is more limited. The present experiment determined the effect of different grazing regimes (high, medium and low defoliation intensity) at the first grazing on subsequent regrowth capability and nutritive characteristics of Winfred (Brassica napus L.) over the summer growing period across 2 years. We hypothesised that intensive defoliation of a summer regrowth brassica at the first grazing will result in lower total DM yields and harvested estimated metabolisable energy (ME) and crude protein per hectare for the growing season than do more lax grazing options that results in less DM removal at the first grazing. Total DM and estimated ME consumed over the growing period varied between years. In Year 1, more (P < 0.05) DM was consumed at the first grazing and less (P < 0.05) at the subsequent grazing for the high-intensity treatment. However, both total DM and estimated ME consumed were higher (P < 0.05) for the high-intensity treatment than for the low-intensity treatment, while in Year 2, there were no differences between the treatments. Nutritive characteristics and mineral concentrations were relatively unaffected by grazing regimes. The results of the present experiment indicated that the optimum grazing management to maximise total DM yields and consumption of spring-sown Winfred will vary depending on the seasonal growing conditions. In years where moisture stress will be limiting crop growth, a high defoliation-intensity first grazing that consumes a high proportion of DM on offer, including some of the main stem, will maximise the total DM grown and consumed from the crop. Care, however, should be taken not to remove all axillary buds from the remaining stems. In summers where moisture stress is not likely to seriously restrict crop growth, a medium defoliation-intensity grazing where the leaf and petiole, but little of the stem, are removed will maximise DM regrowth, leading to maximum total DM grown for the season. A high defoliation-intensity first grazing that removes at least half the stem is, under these conditions, likely to remove too many axillary buds and reduce water-soluble carbohydrate reserves required for DM regrowth, while a lax first grazing will result in a lower DM regrowth.

scholarly journals Defoliation at different vegetative stages and assessment of morphological and yield components

2016 ◽  
Vol 22 (1) ◽  
Author(s):  
Maicon Nardino ◽  
Velci Queiróz de Souza ◽  
Carlos André Bahry ◽  
Ivan Ricardo Carvalho ◽  
Braulio Otomar Caron ◽  
...  
Keyword(s):  
Experimental Design ◽  
Grain Yield ◽  
Water Availability ◽  
Yield Components ◽  
Block Design ◽  
Morphological Characters ◽  
Main Stem ◽  
Stem Height ◽  
Randomized Block Design ◽  
Pod Number

Objective was to evaluate the influence of defoliation of a soybean cultivar indeterminate growth in different vegetative stages on morphological characters and yield components. The study was conducted in the years 2010/11 and 2011/12. The experimental design was a randomized block design with seven treatments and four replications for each year. The treatments were: T1: No defoliation; T2: Defoliation in V4, T3: Defoliation in V4 and V5, T4: Defoliation in V4, V5 and V6, T5: Defoliation in V4, V5, V6 and V7, T6: Defoliation in V4, V5, V6, V7 and V8 and T7: Defoliation in V4, V5, V6, V7, V8 and V9. The variables analyzed were: main stem height, number and length of branches, first pod, number of pods per node on the main stem, and the branches per plant, number of reproductive nodes on the main stem, the branches, number of us total on the main stem, the branches, distance between us and grain yield. Grazing did not influence most of the morphological characters and increments the number of pods on the stem in years with good water availability and high levels of defoliation, and yield of soybean.

The effect of stage of growth on the copper, zinc, manganese, and molybdenum contents of Algerian oats grown of thirteen soils

1952 ◽  
Vol 3 (4) ◽  
pp. 343 ◽  
Author(s):  
CH Williams ◽  
CWE Moore
Keyword(s):  
Trace Metal ◽  
Soil Ph ◽  
Dry Matter ◽  
Growing Period ◽  
Stages Of Growth ◽  
Early Stages ◽  
Copper And Zinc ◽  
Rate Of Increase ◽  
Metal Contents ◽  
Copper Zinc

Algerian oats were grown on 13 soils in the glass-house. Plants were harvested at intervals throughout the growing period, and when large enough were divided into leaf, stem, and (in later harvests) flowers or fruits. Copper, zinc, manganese, and molybdenum were determined on the separate plant fractions. Characteristic changes in the trace metal contents of the plant with growth were found for each element. These changes were generally similar irrespective of the soil on which the plants were grown. With the exception of manganese, the availability of the element in the soil did not affect the trend of the changes as the plant matured, but only the amount present. The uptake of each of the four elements continued through the whole period of growth. The total amounts of copper and zinc in both the leaf and the stem decreased after flowering as translocation to the grain proceeded. The amount of manganese in the leaf increased throughout the period of growth, although the rate of increase was less after flowering. The amount of molybdenum in the leaf increased until flowering, after which there was little further change. The rate of uptake of manganese was approximately equal to the rate of production of dry matter, whereas that of molybdenum, copper, and zinc was relatively greater in the early stages of growth. There was no observable influence of soil pH on the availability of copper and zinc, but that of manganese decreased with increasing pH. The availability of molybdenum was affected by the combined influences of soil pH and soil iron.

Etude cinétique de quelques événements lies à une levée de dominance apicale par décapitation ou ablation de l'axe principal à différents niveaux chez la Tomate, Lycopersicum esculentum

1980 ◽  
Vol 58 (2) ◽  
pp. 281-294
Author(s):  
Kim Anh Ha Ngoc
Keyword(s):  
Apical Dominance ◽  
Main Axis ◽  
Main Stem ◽  
Axillary Buds ◽  
Axillary Bud ◽  
Lycopersicum Esculentum ◽  
Tomato Plants ◽  
Different Levels

In intact tomato plants, axillary buds are completely inhibited by the main apex. A release from apical dominance is obtained by decapitation or excision of the main axis at different levels. These excisions lead to a wave of mitotic reactivation along the main stem which progresses in the basipetal way and is followed by an activation of axillary bud in the acropetal direction, from the base to the axillary bud apex. After release from apical dominance, axillary buds don't react equally. There is a basipetal gradient of their capacity of outgrowth. In the younger subapical axillary buds, mitotic reactivation is the first step observed (after 3 h); the cellular elongation occurs after 3–6 h, and foliar organogenesis begins only after 24 h. The basal axillary buds are reactivated much later. Adult leaves don't play any role on their axiliaries: the total defoliation of the plant does not lead to the outgrowth of all the axillary or cotyledonary buds.

Forme de la plantule et architecture de quelques hêtres, chiliens (Nothofagus) et chinois (Fagus)

1997 ◽  
Vol 75 (4) ◽  
pp. 640-655 ◽  
Author(s):  
B. Thiébaut ◽  
A. Bodin ◽  
I. Sérey ◽  
J.-L. Druelle ◽  
J. Li ◽  
...  
Keyword(s):  
New Species ◽  
New Zealand ◽  
North America ◽  
Key Words ◽  
Growth Process ◽  
Morphological Characters ◽  
The Other ◽  
Main Stem ◽  
Architectural Model

Before studying the inter- and intra-specific plasticity of 13 species of beech from Chile and China, it is necessary to describe precisely their basic architectural model. All these species conform to Troll's architectural model, as the other beech species described so far in North America, Europe, Japan, and New Zealand. This study thus extends the previous observations to new species and allows to bring more precision to definitions of some complex morphological characters of the Troll model: shape of seedlings, transformation of orthotropic axis to plagiotropic axis, differentiated or undifferentiated annual shoots, and growth process of the upper part of the main stem. Key words: Fagus, Nothofagus, morphology, architecture, growth, Chile, China.

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