scholarly journals Hormesis with glyphosate depends on coffee growth stage

2013 ◽  
Vol 85 (2) ◽  
pp. 813-822 ◽  
Author(s):  
LEONARDO B. DE CARVALHO ◽  
PEDRO L.C.A. ALVES ◽  
STEPHEN O. DUKE
Keyword(s):  
Plant Growth ◽  
Weed Management ◽  
Growth Stage ◽  
Growth Stages ◽  
Coffee Plant ◽  
Herbicide Application ◽  
Coffee Plantations ◽  
Plant Growth Stages ◽  
Coffee Plants ◽  
Almost All

Weed management systems in almost all Brazilian coffee plantations allow herbicide spray to drift on crop plants. In order to evaluate if there is any effect of the most commonly used herbicide in coffee production, glyphosate, on coffee plants, a range of glyphosate doses were applied directly on coffee plants at two distinct plant growth stages. Although growth of both young and old plants was reduced at higher glyphosate doses, low doses caused no effects on growth characteristics of young plants and stimulated growth of older plants. Therefore, hormesis with glyphosate is dependent on coffee plant growth stage at the time of herbicide application.

scholarly journals Dosage of 2,6-Bis (1.1-Dimethylethyl)-4-Methylphenol (BHT) in the Plant ExtractMesembryanthemum crystallinum

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Bouftira Ibtissem ◽  
Mgaidi Imen ◽  
Sfar Souad
Keyword(s):  
Antioxidant Activity ◽  
Plant Growth ◽  
Plant Extract ◽  
Growth Stage ◽  
Mesembryanthemum Crystallinum ◽  
Growth Stages ◽  
Naturally Occurring ◽  
Plant Growth Stages

A naturally occurring BHT was identified in the leaves of the halophyte plantMesembryanthemum crystallinum. This phenol was extracted in this study by two methods at the different plant growth stages. One of the methods was better for BHT extraction; the concentration of this phenol is plant growth stage dependent. In this study, the floraison stage has the highest BHT concentration. The antioxidant activity of the plant extract was not related to BHT concentration. The higher antioxidant activity is obtained at seedlings stage.

Dinitrogen fixation in Phaseolus vulgaris at low temperatures: interaction of temperature, growth stage, and time of inoculation

1982 ◽  
Vol 60 (8) ◽  
pp. 1423-1427 ◽  
Author(s):  
R. J. Rennie ◽  
G. A. Kemp
Keyword(s):  
Phaseolus Vulgaris ◽  
Plant Growth ◽  
Root Growth ◽  
Low Temperatures ◽  
Growth Stage ◽  
Growth Stages ◽  
Trifoliate Leaf ◽  
Temperature Growth ◽  
Southern Alberta ◽  
Plant Growth Stages

Nodulation and N2 fixation have not been reported in beans (Phaseolus vulgaris L.) below a temperature of 13 °C but, in southern Alberta, temperatures at planting may be as low as 10 °C. Two varieties of pea beans, 'Aurora' and 'Kentwood,' were inoculated at three growth stages (seeding, primary leaf horizontal, or first trifoliate leaf open) and grown at 10, 12, 14, or 16 °C. Nodulation and acetylene (C2H2) reduction occurred in both varieties at temperatures as low as 10 °C. At the lower temperatures, cold adaptability of the plant for early root growth determined the ability for nodulation and N2 fixation. At higher temperatures, plant-growth stage was a determining factor. 'Aurora' was superior to 'Kentwood' at 10 °C in nodulation, dry matter (DM), N yield, and N2 fixation because of its tolerance to low temperatures during early root growth. Inoculation with Rhizobium phaseoli at more advanced plant-growth stages decreased the time for nodulation at all four temperatures but resulted in higher yield and more N2 fixation in 'Aurora' only at 14 and 16 °C. At 10 °C, inoculation at seeding was more effective than at the other two growth stages for both varieties. Thus plant growth stages and growth temperature both determined the ability of a bean variety to support N2 fixation at various low temperatures.

Herbicidal control of deathcamas (Zigadenus paniculatus)

2020 ◽  
pp. 1-5
Author(s):  
Clinton A. Stonecipher ◽  
Corey Ransom ◽  
Eric Thacker ◽  
Kevin Welch ◽  
Dale R. Gardner ◽  
...  
Keyword(s):  
Plant Growth ◽  
Growth Stage ◽  
Control Agent ◽  
Alkaloid Content ◽  
Western United States ◽  
Growth Stages ◽  
Herbicide Application ◽  
The Mean ◽  
Similar Density ◽  
The Impact

Abstract Foothill deathcamas is a bulbous, perennial, native forb found throughout the western United States. Deathcamas begins growth early in the spring. The lack of alternative forages at this time can result in livestock becoming poisoned from the consumption of deathcamas. Research on herbicides for deathcamas control is limited to work from the 1950s and 1960s that identified 2,4-D as a control agent. The objective of this study was to evaluate alternative herbicide options for deathcamas control that include 2,4-D, 2,4-D + triclopyr, quinclorac, aminopyralid, imazapic, and chlorsulfuron. We also investigated the impact of plant growth stage on deathcamas control by making herbicide applications at two growth stages. One set of plots was treated with herbicides when deathcamas was in the early vegetative stage and the second set was treated at flowering. There is some evidence that stress might affect alkaloid content; therefore, we monitored alkaloid content of treated and nontreated deathcamas. Plots were established at Mt. Sterling, UT, and Mt. Pleasant, UT. Deathcamas density was reduced in 2,4-D, 2,4-D + triclopyr, and imazapic treatments 1 and 2 yr after herbicide application (P < 0.0001). Compared with the pretreatment densities, deathcamas densities(± standard error of the mean) 2 yr after herbicide application were reduced 96% ± 1.4%, 100% ± 0%, and 98% ± 0.9% for 2,4-D, 2,4-D + triclopyr, and imazapic, respectively, at the Mt. Sterling site. At the Mt. Pleasant site, deathcamas density was reduced by 84% ± 2.8% with 2,4-D alone, whereas 2,4-D + triclopyr and imazapic provided similar density reductions as observed at the Mt. Sterling site. Steroidal alkaloid concentrations did not change in herbicide-treated deathcamas at either stage of plant growth. These data indicate that 2,4-D, 2,4-D + triclopyr, and imazapic can effectively control deathcamas in the vegetative and flowering growth stages.

scholarly journals Efficacy of Deep Learning Algorithm in Classifying Chilli Plant Growth Stages

2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Danial Mirza Muammar Rozilan ◽  
Marsyita Hanafi ◽  
Roslizah Ali ◽  
Mohd Adib Razak ◽  
Cui Hairu
Keyword(s):  
Deep Learning ◽  
Plant Growth ◽  
Growth Stage ◽  
Learning Algorithm ◽  
Automatic Identification ◽  
Growth Stages ◽  
Growth Monitoring ◽  
Learning Approaches ◽  
Learning Methods ◽  
Plant Growth Stages

Automatic plant growth monitoring has received considerable attention in recent years. The demand in this field has created various opportunities, especially for automatic classification using deep learning methods. In this paper, the efficiency of deep learning algorithms in classifying the growth stage of chili plants is studied. Chili is one of the high cash value crops, and automatic identification of chili plant growth stages is essential for crop productivity. Nevertheless, the study on automatic chili plant growth stage classification using deep learning approaches is not widely explored, and this is due to the unavailability of public datasets on the chili plant growth stages. Various deep learning methods, namely Inception V3, ResNet50, and VGG16, were used in the study, and the results have shown that these methods performed well in terms of accuracy and stability when tested on a dataset that consists of 2,320 images of Capsicum annum 'Bird's Eye' plants of various growth stages and imaging conditions. Nevertheless, the results have also shown that the deep learning methods have difficulty classifying images with a complex background where more than one chili plant was captured in an image.

Efficacy of insecticidal applications based on calendar intervals and plant growth stages for control of insect pests on cowpea

1995 ◽  
Vol 16 (1) ◽  
pp. 109-112 ◽  
Author(s):  
Aliyageen M. Alghali
Keyword(s):  
Plant Growth ◽  
Growth Stage ◽  
Insect Pests ◽  
Growth Stages ◽  
Grain Yields ◽  
Plant Growth Stages ◽  
Cowpea Varieties

AbstractStudies were carried out to compare the efficacy of insecticide schedules based on calendar intervals with those based on plant growth stages for the control of cowpea insect pests. Spray schedules based on calendar intervals and plant growth stage gave reasonable control of the pest complex and increased grain yields significantly. However, spray schedules based on plant growth stages alone were more efficient for two of the three cowpea varieties tested. This was attributed to differences in maturity periods which made spraying by regular calendar intervals slightly out of phase with attack by key insect pests. Thus, spray schedules based on plant growth stages are recommended for the control of insect pests of cowpea.

scholarly journals IBA Formulation, Concentration, and Stock Plant Growth Stage Affect Rooting of Stem Cuttings of Viburnum rufidulum

2008 ◽  
Vol 26 (1) ◽  
pp. 1-3
Author(s):  
Jason J. Griffin
Keyword(s):  
Plant Growth ◽  
Growth Stage ◽  
Adventitious Rooting ◽  
Growth Stages ◽  
Stem Cuttings ◽  
Stock Plant ◽  
Indolebutyric Acid ◽  
Rooted Cutting ◽  
Landscape Plant ◽  
Plant Growth Stages

Abstract Viburnum rufidulum Raf. (southern or rusty blackhaw) has potential to be a popular landscape plant as it is an attractive large shrub tolerant of many common landscape stresses. However, propagation difficulties have thus far limited wide scale use. Therefore, the influence of IBA formulation and concentration on adventitious rooting of stem cuttings of southern blackhaw taken at different stock plant growth stages throughout the year were investigated. Liquid formulations of the potassium salt (K-salt) of indolebutyric acid (K-IBA) at 0, 3000, 6000, or 9000 ppm (0, 0.3, 0.6, or 0.9%) as well as talc formulations of IBA at 1000, 3000, or 8000 ppm (0.1, 0.3 or 0.8%) were utilized. Talc formulations failed to stimulate rooting regardless of concentration or growth stage. A quick-dip of K-IBA increased rooting percentage at all growth stages. Softwood and hardwood cuttings had the highest rooting percentages. Hardwood cuttings treated with 6000 ppm (0.6%) or 9000 ppm (0.9%) rooted 90 and 100%, respectively. Softwood cuttings treated with 6000 ppm (0.6%) rooted 87%. K-IBA improved root number per rooted cutting for softwood cuttings, whereas root length was unaffected by K-IBA at any growth stage.

scholarly journals Stand Reduction and Foliage Damage Reduce Yield of Dehydrating Onion

HortScience ◽  
2004 ◽  
Vol 39 (5) ◽  
pp. 1005-1007 ◽  
Author(s):  
George H. Clough
Keyword(s):  
Plant Growth ◽  
Growth Stage ◽  
Leaf Growth ◽  
Field Trials ◽  
Growth Stages ◽  
Leaf Stage ◽  
Plant Growth Stages ◽  
The Impact ◽  
Stage Yield ◽  
Different Growth Stages

Field trials were conducted at Hermiston, Ore., from 1995 through 1998, to determine impact of stand loss and plant damage at different growth stages on yield of onions (Allium cepa) grown for dehydration. Stand reduction (0%, 20%, 40%, 60%, 80%) and foliage damage (0%, 25%, 50%, 75%, 100%) treatments were applied at three-, six-, nine-, and twelve-leaf onion growth stages. Although average bulb weight increased as stand was reduced, marketable, cull, and total yields decreased as stand reduction increased (plant population decreased) at all plant growth stages. Bulb weight was not changed by up to 100% foliage removal at the three-leaf stage. At the six- and twelve-leaf stages, weight was reduced when ≥50% of the foliage was removed. The most severe response occurred at the nine-leaf stage. At the three-leaf stage, yield was not affected by foliage damage. At the six-leaf growth stage, yield was reduced by 75% or more foliage loss, but at the nine- and twelve-leaf stages, ≥50% foliage removal reduced expected yields. As with bulb weight, the impact of foliage removal on yield was most severe at the nine-leaf growth stage.

Developmental stability, canalization and phenotypic plasticity in annual herbaceous species under different biotic and abiotic conditions

2021 ◽  
Author(s):  
Shu Wang ◽  
Dao-Wei Zhou
Keyword(s):  
Phenotypic Plasticity ◽  
Plant Growth ◽  
Mean Value ◽  
Developmental Stability ◽  
Soil Conditions ◽  
Growth Stages ◽  
Herbaceous Species ◽  
Fertile Soil ◽  
Plant Growth Stages ◽  
Positive Correlations

Abstract The relationships among developmental stability, canalization and phenotypic plasticity have not been well understood. Inconsistent conclusions from different studies suggested the complexity of their associations, probably depending on specific traits, environmental contexts and plant growth stages. To address this issue, we conducted three experiments (EXP I ~ III) with several annual herbaceous species, to investigate the relationships among leaf (or cotyledon) developmental stability, canalization and plasticity and their variations with different biotic and abiotic environmental conditions and plant growth stages, with comparisons among different species at their early growth stage. We analyzed variations in mean trait value, lamina fluctuating asymmetry (FA), coefficient of variation (CV) and plasticity (RDPIs) and their correlations for lamina size (LS) of individual plants, for LS, petiole length (PL) and petiole angle (PA) of different plant layers in Abutilon theophrasti at three densities in infertile and fertile (or only fertile) soil conditions at three (or two) stages, and for cotyledon size (CS) of five species in contrasting light conditions and seeding depths. High vs. low density decreased LS (with negative RDPIs), FA indexes and CVs, either for individual plants or different layers, especially in fertile soil. Shading was more likely to increase CS (except for A. therophrasti) and FA and decrease CV; deep seeding increased CS of some species in full light, but decreased CS and FA of other species in shading (except for A. therophrasti). FA indexes more likely had positive correlations with mean value, CV and RDPIs of traits; correlations between CV and RDPIs can be positive, negative or insignificant. Correlations among the three variables were more likely positive or insignificant for traits of LS, CS and PL, but more likely negative or insignificant for PA. High density and infertile soil may favor more positive over negative correlations among variables. Results suggested higher levels of lamina FA more likely indicate higher growth rates of plants or modules. Developmental stability was more likely to have positive correlations with canalization, and negative correlations with plasticity, indicating certain common mechanisms associated with them. Environmental stresses can lead to greater phenotypic variations at different levels, facilitating cooperation between the three processes in dealing with environmental challenges.

scholarly journals Scale-Dependent Effects of Growth Stage and Elevational Gradient on Rice Phyllosphere Bacterial and Fungal Microbial Patterns in the Terrace Field

2022 ◽  
Vol 12 ◽  
Author(s):  
Pei Wang ◽  
Jianping Dai ◽  
Luyun Luo ◽  
Yong Liu ◽  
Decai Jin ◽  
...  
Keyword(s):  
Plant Growth ◽  
Growth Stage ◽  
Elevational Gradient ◽  
Fungal Communities ◽  
Growth Stages ◽  
Strong Positive Correlation ◽  
Elevation Gradients ◽  
Positive Correlation ◽  
Α Diversity ◽  
Phyllosphere Bacteria

The variation of phyllosphere bacterial and fungal communities along elevation gradients may provide a potential link with temperature, which corresponds to an elevation over short geographic distances. At the same time, the plant growth stage is also an important factor affecting phyllosphere microorganisms. Understanding microbiological diversity over changes in elevation and among plant growth stages is important for developing crop growth ecological theories. Thus, we investigated variations in the composition of the rice phyllosphere bacterial and fungal communities at five sites along an elevation gradient from 580 to 980 m above sea level (asl) in the Ziquejie Mountain at the seedling, heading, and mature stages, using high-throughput Illumina sequencing methods. The results revealed that the dominant bacterial phyla were Proteobacteria, Actinobacteria, and Bacteroidetes, and the dominant fungal phyla were Ascomycota and Basidiomycota, which varied significantly at different elevation sites and growth stages. Elevation had a greater effect on the α diversity of phyllosphere bacteria than on that phyllosphere fungi. Meanwhile, the growth stage had a great effect on the α diversity of both phyllosphere bacteria and fungi. Our results also showed that the composition of bacterial and fungal communities varied significantly along elevation within the different growth stages, in terms of both changes in the relative abundance of species, and that the variations in bacterial and fungal composition were well correlated with variations in the average elevation. A total of 18 bacterial and 24 fungal genera were significantly correlated with elevational gradient, displaying large differences at the various growth stages. Soluble protein (SP) shared a strong positive correlation with bacterial and fungal communities (p &lt; 0.05) and had a strong significant negative correlation with Serratia, Passalora, unclassified_Trichosphaeriales, and antioxidant enzymes (R &gt; 0.5, p &lt; 0.05), and significant positive correlation with the fungal genera Xylaria, Gibberella, and Penicillium (R &gt; 0.5, p &lt; 0.05). Therefore, it suggests that elevation and growth stage might alter both the diversity and abundance of phyllosphere bacterial and fungal populations.

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