Periodicity of leaf growth and leaf dry mass changes in the evergreen and deciduous species of Southern Assam, India

2013 ◽  
Vol 29 (2) ◽  
pp. 153-165 ◽  
Author(s):  
Florida Devi Athokpam ◽  
S. C. Garkoti ◽  
N. Borah
Keyword(s):  
Leaf Growth ◽  
Dry Mass ◽  
Deciduous Species ◽  
Leaf Dry Mass

scholarly journals Growth, nutrient accumulation and yield of onion as a function of micronutrient fertilization

2022 ◽  
Vol 26 (2) ◽  
pp. 126-134
Author(s):  
Nubia M. F. Bertino ◽  
Leilson C. Grangeiro ◽  
João P. N. da Costa ◽  
Romualdo M. C. Costa ◽  
Rodolfo R. de A. Lacerda ◽  
...  
Keyword(s):  
Cell Function ◽  
Leaf Growth ◽  
Dry Mass ◽  
Growth And Yield ◽  
Leaf Dry Mass ◽  
Class 1 ◽  
Zn And Cu In ◽  
Number Of Leaves ◽  
Commercial Yield ◽  
Cu And Zn

ABSTRACT Micronutrients structurally constitute several enzymes and act as a cofactor of essential proteins to maintain cell function, thereby contributing to crop growth and yield. The objective of this study was to evaluate the leaf content, growth, accumulation of micronutrients, classification and yield of onion as a function of fertilization with boron, cooper and zinc in two years of cultivation. The experiments were carried out from June to November in 2018 and 2019, in a soil classified as Ultisol, both at the Rafael Fernandes Experimental Farm, belonging to the Universidade Federal Rural do Semiárido, in the municipality of Mossoró, Rio Grande do Norte, Brazil. The experimental design was in randomized blocks with 15 treatments and four replicates. The treatments consisted of application of doses of B, Cu and Zn, in two experiments. Contents of B, Cu and Zn in the diagnostic leaf, growth, accumulation of B, Cu and Zn in the leaf, bulb and total, classification and commercial, non-commercial and total yields were evaluated. Application of B, Cu and Zn did not influence the number of leaves, relation of bulb shape, leaf, bulb, and total dry mass and yield of onion. Application of B, Cu and Zn, respectively at doses of 1-2-1 kg ha-1 favored a greater accumulation of B, Zn and Cu in the bulb. Higher number of leaves, leaf dry mass, bulb dry mass, total dry mass, class 1 bulbs and non-commercial yield were produced in Experiment 1.

scholarly journals Physiological responses of two tropical weeds to shade: I. Growth and biomass allocation

1999 ◽  
Vol 34 (6) ◽  
pp. 944-952 ◽  
Author(s):  
Moacyr Bernardino Dias-Filho
Keyword(s):  
Leaf Area ◽  
Weed Management ◽  
Dry Mass ◽  
High Light ◽  
Low Light ◽  
Light Regimes ◽  
Leaf Dry Mass ◽  
Lower Ability ◽  
Total Plant ◽  
Plant Dry Mass

Ipomoea asarifolia (Desr.) Roem. & Schultz (Convolvulaceae) and Stachytarpheta cayennensis (Rich) Vahl. (Verbenaceae), two weeds found in pastures and crop areas in Brazilian Amazonia, were grown in controlled environment cabinets under high (800-1000 µmol m-² s-¹) and low (200-350 µmol m-² s-¹) light regimes during a 40-day period. For both species leaf dry mass and leaf area per total plant dry mass, and leaf area per leaf dry mass were higher for low-light plants, whereas root mass per total plant dry mass was higher for high-light plants. High-light S. cayennensis allocated significantly more biomass to reproductive tissue than low-light plants, suggesting a probably lower ability of this species to maintain itself under shaded conditions. Relative growth rate (RGR) in I. asarifolia was initially higher for high-light grown plants and after 20 days started decreasing, becoming similar to low-light plants at the last two harvests (at 30 and 40 days). In S. cayennensis, RGR was also higher for high-light plants; however, this trend was not significant at the first and last harvest dates (10 and 40 days). These results are discussed in relation to their ecological and weed management implications.

scholarly journals Environmental controls over methanol emission from leaves

2007 ◽  
Vol 4 (4) ◽  
pp. 2593-2640 ◽  
Author(s):  
P. Harley ◽  
J. Greenberg ◽  
Ü. Niinemets ◽  
A. Guenther
Keyword(s):  
Stomatal Conductance ◽  
Leaf Growth ◽  
Dry Mass ◽  
Leaf Temperature ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Emission Model ◽  
Production Term ◽  
Methanol Production ◽  
Environmental Controls

Abstract. Methanol is found throughout the troposphere, with average concentrations second only to methane among atmospheric hydrocarbons. Proposed global methanol budgets are highly uncertain, but all agree that at least 60% of the total source arises from the terrestrial biosphere and primary emissions from plants. However, the magnitude of these emissions is also highly uncertain, and the environmental factors which control them require further elucidation. Using a temperature-controlled leaf enclosure, we measured methanol emissions from leaves of six plant species by proton transfer reaction mass spectrometry, with simultaneous measurements of leaf evapotranspiration and stomatal conductance. Rates of emission at 30°C varied from 0.3 to 38 μg g (dry mass)−1 h−1, with higher rates measured on young leaves, consistent with the production of methanol via pectin demethylation in expanding foliage. On average, emissions increased by a factor of 2.4 for each 10°C increase in leaf temperature. At constant temperature, emissions were also correlated with co-varying incident photosynthetic photon flux density and rates of stomatal conductance. The data were analyzed using the emission model developed by Niinemets and Reichstein (2003a, b), with the incorporation of a methanol production term that increased exponentially with temperature. It was concluded that control of emissions, during daytime, was shared by leaf temperature and stomatal conductance, although rates of production may also vary diurnally in response to variations in leaf growth rate in expanding leaves. The model, which generally provided reasonable simulations of the measured data during the day, significantly overestimated emissions on two sets of measurements made through the night, suggesting that production rates of methanol were reduced at night, perhaps because leaf growth was reduced or possibly through a direct effect of light on production. Although the short-term dynamics of methanol emissions can be successfully modeled only if stomatal conductance and compound solubility are taken into account, emissions on longer time scales will be determined by rates of methanol production, controls over which remain to be investigated.

scholarly journals Sensitivity of Shoots and Roots of Young Watermelon Plants to End-of-day Red and Far-red Light

1997 ◽  
Vol 122 (4) ◽  
pp. 481-484
Author(s):  
Heather A. Hatt Graham ◽  
Dennis R. Decoteau
Keyword(s):  
Citrullus Lanatus ◽  
Red Light ◽  
Dry Mass ◽  
Stem Length ◽  
Hoagland Solution ◽  
Full Strength ◽  
Leaf Dry Mass ◽  
Half Strength

The sensitivity of shoots and roots to end-of-day (EOD) red (R) or far-red (FR) light on growth of `Sugar Baby' watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai] was investigated. Plants were grown in full-strength Hoagland solution and treated for 14 days to 15 minutes EOD light in trial 1 and in half-strength Hoagland solution and treated for 10 days to EOD light in trial 2. Exposing shoots to EOD FR resulted in elongated petioles of leaves 1 to 3 (as counted from the cotyledons), internodes 1 to 3, and total stem length in both trials. Exposure to EOD FR resulted in increased stem and petiole dry mass in trial 1, whereas EOD FR resulted in increased root and leaf dry mass in trial 2. EOD FR exposure of roots increased the length of petiole 4 in trial 1. In general, shoots were more responsive than roots to the growth-regulating effects of EOD FR.

scholarly journals FLAME RETARDANTS EFFECTS ON THE INITIAL GROWTH OF Schizolobium amazonicum HUBER EX DUCKE

2021 ◽  
Vol 45 ◽  
Author(s):  
Elen Silma Oliveira Cruz Ximenes ◽  
Andréa Carvalho da Silva ◽  
Adilson Pacheco de Souza ◽  
Josiane Fernandes Keffer ◽  
Alison Martins dos Anjos ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Leaf Area ◽  
Flame Retardants ◽  
Biomass Accumulation ◽  
Dry Mass ◽  
Initial Growth ◽  
Environmental Implications ◽  
Leaf Dry Mass ◽  
Height Increase ◽  
Positive Effect

ABSTRACT Flame retardants are efficient in fighting wildfire; however, their environmental implications, especially regarding the vegetation, need to be clarified. This work aimed at assessing the effects of flame retardant on the initial growth of Schizolobium amazonicum. Treatments consisted in applying different flame retardant concentrations via substrate and leaf: Phos-Chek WD-881® (0, 3.00, 6.00, 8.00 and 10.00 mL L-1), Hold Fire® (0, 7.00, 9.00, 12.00 and 15.00 mL L-1) and water-retaining polymer Nutrigel® used as alternative retardant (0, 0.25, 0.50, 0.75 and 1.00 g L-1). Growth analyses were carried out to assess the effects of these substances (10 repetitions per treatment). The aliquot of 10.00 mL L-1 of Phos-Chek WD881 applied on the leaves led to an increase of 70% in leaf area and 15% in seedling height. The same Phos-Chek concentration favored height increase (32%) and total dry mass accumulation (33%) throughout time. The concentration of 15 mL L-1 of Hold Fire® applied on leaves, compromised 45% the accumulation of dry biomass in the seedling. Initially, 1.00 g L-1 of Nutrigel® applied via substrate led to an increase of 70% in leaf area, 29% in plant height, and 89% in leaf dry mass. Therefore, Phos-Chek applied on leaves favored shoot growth in S. amazonicum. Hold Fire® applied on leaves impaired biomass accumulation in seedlings. Nutrigel® applied on substrate does not cause long-lasting damage to the initial growth of S. amazonicum. The aliquot of 0.50 g L-1 administered via polymer leave had positive effect on seedling shoot.

scholarly journals Effect of dose and application site on quinclorac absorption by barnyardgrass biotypes

2009 ◽  
Vol 27 (3) ◽  
pp. 541-548 ◽  
Author(s):  
G. Concenço ◽  
A.F. Silva ◽  
E.A. Ferreira ◽  
L. Galon ◽  
J.A. Noldin ◽  
...  
Keyword(s):  
Logistic Model ◽  
Dry Matter ◽  
Leaf Growth ◽  
Linear Regression Analysis ◽  
Resistance Index ◽  
Dry Mass ◽  
Application Site ◽  
Recommended Dosage ◽  
Plant Parts ◽  
Nutritive Solution

This work aimed to evaluate the uptake and translocation of quinclorac in function of application sites (shoot or roots) by Echinochloa crusgalli biotypes resistant and susceptible to this herbicide. The treatments consisted of quinclorac doses (0; 0.5; 1; 2; 4; 16 and 64 ppm), applied on the shoot or roots of seedlings of barnyardgrass biotypes. The experimental units consisted of plastic cups containing 250 cm³ of sand. The treatments were applied 10 days after emergence, when barnyardgrass plants reached a 2- to 3- leaf growth stage. The barnyardgrass biotypes were irrigated with nutritive solution weekly and maintained for 40 days after emergence, when length, fresh and dry matter of shoot and roots were evaluated. Variance analysis was carried out using the F test at 5% probability, and in case of significance, a non-linear regression analysis was also carried out using a three-parameter logistic model. In the susceptible biotype, quinclorac was more absorbed by the roots than by the shoot. Comparing dry mass production of the different plant parts of the susceptible biotype per application site, it was verified that quinclorac action is higher when applied to the plant roots. However, for the resistant biotype, it was not possible to determine the dose causing 50% reduction in dry mass accumulation (GR50) and in the resistance index (RI) between both biotypes, due to its high resistance to quinclorac (128 times the recommended dosage). The results showed that quinclorac resistance by the evaluated biotype is not due to differences in the absorption site, strongly suggesting that the resistance acquired by the biotype may result from alteration in the target site.

The behaviour of plants in various gas mixtures

1971 ◽  
Vol 179 (1056) ◽  
pp. 177-188
Keyword(s):  
Carbon Dioxide ◽  
Gas Exchange ◽  
Partial Pressure ◽  
Higher Plants ◽  
Dry Mass ◽  
Carbon Dioxide Partial Pressure ◽  
Ambient Oxygen ◽  
Leaf Dry Mass ◽  
Rate Of Photosynthesis ◽  
Effect Of Oxygen

The effects of the composition and pressure of the ambient gas mixture on the diffusive gas exchange of leaves, and the effects of carbon dioxide and oxygen on respiration and photosynthesis are described. When photosynthesis is limited by the rate at which carbon dioxide reaches the chloroplasts, the net rate of photosynthesis of many (but not all) plant species depends on the ambient oxygen partial pressure. The effect of oxygen may be principally to stimulate a respiratory process rather than to inhibit carboxylation. However, when photosynthesis is not limited by the carbon dioxide supply, this respiratory process seems to be suppressed. The gas exchange of plant communities responds to the aerial environment in the way expected from measurements on single leaves, but the growth response to a given difference in gas composition is smaller than expected because of adaptation, notably in the ratio of leaf dry mass to leaf area. It is concluded that the growth rate of higher plants in given illumination will be independent of the partial pressure of oxygen and of other gases likely to be used to dilute it, provided that the carbon dioxide partial pressure is so adjusted (probably to not more than 2 mbar (200 Pa)) that the rate of photosynthesis is not limited by the rate of diffusion to the chloroplasts.

The response of vacuolar phenolic content of common bean (Phaseolus vulgaris cv. Bergamo) to a chronic ozone exposure: questions and hypotheses

2002 ◽  
Vol 29 (1) ◽  
pp. 1 ◽  
Author(s):  
Jean-Philippe Biolley ◽  
Myriam Kanoun ◽  
Philippe Goulas
Keyword(s):  
Phaseolus Vulgaris ◽  
Common Bean ◽  
Exposure Time ◽  
Ozone Concentration ◽  
Leaf Growth ◽  
Total Content ◽  
Dry Mass ◽  
Ozone Exposure ◽  
Ozone Stress ◽  
Atmospheric Concentrations

Using open-top chamber technology, we investigated the foliar phenolic response of common bean (Phaseolus vulgaris L. cv. Bergamo) to a chronic, moderate ozone stress. Three atmospheric concentrations of ozone were tested: non-filtered air (NF) prevailing at the experimental site, and non-filtered air supplied with 40 (NF+40) and 60 nL L–1 ozone (NF+60), respectively. Both constitutive and ozone-induced non-polymerized phenolics were considered with regards to pollutant concentration, exposure time, leaf type (primary or trifoliate), and leaf growth. The biomass of primary leaves was unaffected by the tested ozone concentrations, whereas dry mass of first and second trifoliate leaves significantly decreased as atmospheric ozone increased. Characteristic symptoms were observed on the upper surface of leaves from the two ozone-supplied treatments. Their severity reflected both leaf exposure time and ozone concentration. As a whole, the total content of foliar soluble constitutive phenolics remained unchanged as the ozone increased, even for leaves almost totally covered with dark-brown discolourations. Nonetheless, among the three main detected phenolics, the accumulation of the kaempferol derivative could be significantly stimulated by ozone. Also, six ozone-induced phenolics could be synthesized by leaves exposed to the two pollutant-enriched atmospheres, and their elicitation and amount were closely connected with both exposure time and ozone concentration.

Leaf growth and K+/Na+ ratio as an indication of the salt tolerance of three sorghum cultivars grown under salinity stress and IAA treatment

2004 ◽  
Vol 52 (3) ◽  
pp. 287-296 ◽  
Author(s):  
M. M. Azooz ◽  
M. A. Shaddad ◽  
A. A. Abdel-Latef
Keyword(s):  
Salt Tolerance ◽  
Water Content ◽  
Leaf Area ◽  
Salinity Stress ◽  
Relative Water Content ◽  
Leaf Growth ◽  
Dry Mass ◽  
Inhibitory Effect ◽  
Tolerance Index ◽  
Relative Water

The salt tolerance of three sorghum (Sorghum bicolor L.) cultivars (Dorado, Hagen Shandawil and Giza 113) and their responses to shoot spraying with 25 ppm IAA were studied. Salinity stress induced substantial differences between the three sorghum cultivars in the leaf area, dry mass, relative water content and tolerance index of the leaves. Dorado and Hagen Shandawil tolerated salinity up to 88 and 44 mM NaCl, respectively, but above this level, and at all salinity levels in Giza 113, a significant reduction in these parameters was recorded. The rate of reduction was lower in Dorado than in Hagen Shandawil and Giza 113, allowing the sequence Dorado ? Hagen Shandawil ? Giza 113 to be established for the tolerance of these cultivars to salinity. The differences in the tolerance of the sorghum cultivars were associated with large differences in K+ rather than in Na+, which was found to be similar in the whole plant. The youngest leaf was able to maintain a higher K+ content than the oldest leaf. Consequently the K+/Na+ ratios were higher in the most salt-tolerant cultivar Dorado than in the other sorghum cultivars, and in the youngest than in the oldest leaf. In conformity with this mechanism, the stimulatory effect of the exogenous application of IAA was mostly associated with a higher K+/Na+ ratio. Shoot spraying with IAA partially alleviated the inhibitory effect of salinity on leaf growth and on the K+ and Ca2+ contents, especially at low and moderate levels of salinity, while it markedly retarded the accumulation of Na+ in the different organs of sorghum cultivars. Abbreviations: LA: Leaf area, DM: Dry mass, I Indole acetic acid, RWC: Relative water content,TI: Tolerance index

scholarly journals Environmental Impact On Morphological and Anatomical Structure of Ricinus communis L. Leaves Growing in Kathmandu, Nepal

2019 ◽  
Vol 7 (2) ◽  
pp. 274-278
Author(s):  
Belai Meeta Singh Suwal ◽  
Ratna Silwal Gautam ◽  
Dikshya Manandhar
Keyword(s):  
Climatic Factors ◽  
Ricinus Communis ◽  
Dry Mass ◽  
Anatomical Features ◽  
Ricinus Communis L ◽  
Leaf Dry Mass ◽  
Polluted Sites ◽  
Study Sites ◽  
The Comparative Study ◽  
The Impact

The current study was done to examine the impact of environmental pollution on morphology and anatomy of leaf of Ricinus communis L. of Kathmandu. The comparative study was done between the plants of high polluted sites i.e Ringroad sides and less polluted sites i.e Raniban forest of Kathmandu. The plants from both sites showed visible morphological and anatomical changes in leaves. These both study sites were found with similar soil factors and climatic factors. Reductions in some morphological and anatomical features were observed in leaves growing in highly polluted site. Reduction in leaf area, petiole length, thickness of palisade layer and thickness of spongy parenchyma was noticed in the leaves from highly polluted sites of Kathmandu. Other morphological and anatomical features such as leaf dry mass content, stomata frequency, thickness of cuticle and size of epidermal cells were noticed to be increased in leaves from highly polluted sites. Int. J. Appl. Sci. Biotechnol. Vol 7(2): 274-278  

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