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

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 < 0.05) and had a strong significant negative correlation with Serratia, Passalora, unclassified_Trichosphaeriales, and antioxidant enzymes (R > 0.5, p < 0.05), and significant positive correlation with the fungal genera Xylaria, Gibberella, and Penicillium (R > 0.5, p < 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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Yield prediction and nitrogen recommendation in maize using normalized difference vegetation index

Agronomy Journal of Nepal ◽

10.3126/ajn.v3i0.9009 ◽

2013 ◽

Vol 3 ◽

pp. 82-88 ◽

Cited By ~ 1

Author(s):

TB Karki

Keyword(s):

Grain Yield ◽

Growth Stage ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Correlation Coefficients ◽

Growth Stages ◽

Strong Positive Correlation ◽

Positive Correlation ◽

Nutrient Levels ◽

Seed Sowing

A study was carried out using three maize genotypes with three levels of nitrogen (30 kg, 60 kg and 120 kg per hectare) during the summer season of 2010 and 2011with the aim of predicting maize (Zea mays L.) yield through the Normalized difference vegetation index (NDVI). The NDVI was recorded at different times throughout the growing season using a Greenseeker™ handheld sensor. Significant effect of genotypes and nutrient levels on the NDVI was observed at different growth stages of maize. There was positive correlation between the NDVI and grain yield. In the first season, the correlation coefficients were 0.90, 0.92, 0.76 and 0.73, respectively at 15, 45, 75 and 110 days after seeding. In the second season, the correlation coefficients were 0.80, 0.92, 0.77 and 0.75 respectively at 15, 45, 75 and 110 days after seeding. The NDVI based N calculator showed that irrespective of genotypes, yield potentials under farmers' levels of nutrient management were almost half of the recommended doses of nitrogen. The amount of N to be top dressed decreased with increased crop duration. Grain yield varied significantly due to season, genotypes and nutrient levels. NDVI was affected due to season, stages of the crop (DAS), genotypes and nutrient levels. Interaction effects were significant for season x genotype, growth stage x genotype, growth stage x nutrient levels, genotype x nutrient levels and genotype x growth stage x nutrient levels. There was a strong positive correlation between NDVI and grain yields of hybrid maize at 15 and 45 DAS, but this correlation declined thereafter. This means that N top-dressed at or after 75 days of seed sowing will not increase grain yield as significantly as N applied earlier in the season. In contrast, topdressed N was producing significant effects on the open pollinated Rampur Composite even after 75 days of seed sowing. Further confirmation of the finding could be useful for top dressing N in the maize crop. Agronomy Journal of Nepal (Agron JN) Vol. 3. 2013, Page 82-88 DOI: http://dx.doi.org/10.3126/ajn.v3i0.9009

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Hormesis with glyphosate depends on coffee growth stage

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652013005000027 ◽

2013 ◽

Vol 85 (2) ◽

pp. 813-822 ◽

Cited By ~ 25

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.

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Efficacy ofColletotrichum coccodesand Thidiazuron for Velvetleaf (Abutilon theophrasti) Control in Soybean (Glycine max)

Weed Technology ◽

10.1017/s0890037x00032292 ◽

1988 ◽

Vol 2 (4) ◽

pp. 473-480 ◽

Cited By ~ 25

Author(s):

Richard H. Hodgson ◽

Lee A. Wymore ◽

Alan K. Watson ◽

Robert H. Snyder ◽

Anne Collette

Keyword(s):

Glycine Max ◽

Plant Growth ◽

Growth Regulator ◽

Plant Growth Regulator ◽

Growth Stage ◽

Pathogenic Fungus ◽

Abutilon Theophrasti ◽

Colletotrichum Coccodes ◽

Growth Stages ◽

Wet Weather

The plant pathogenic fungusColletotrichum coccodes(Cc) and the plant growth regulator thidiazuron (TDZ) were evaluated in Maryland and Quebec for velvetleaf control in ‘Williams' and ‘Maple Arrow’ soybean. TDZ was applied at 0, 0.1, 0.2, 0.3, and 0.4 kg ai/ha alone or was combined with Cc at 109spores/m2when velvetleaf was at the 1- to 2-leaf (Trial 1) or 4- to 6-leaf (Trial 2) growth stages. Velvetleaf control increased with TDZ rate, and TDZ combined with Cc further increased control. TDZ reduced velvetleaf biomass and height, and Cc increased velvetleaf mortality. In Quebec, Cc also reduced the biomass of velvetleaf treated in Trial 1 and interacted positively with TDZ at this growth stage. Cc nearly halved the rates of TDZ required for 90 and 75% mortality of velvetleaf treated at the 1- to 2-leaf and 4- to 6-leaf stages to 0.09 and 0.12 kg/ha, respectively, in Quebec. Cc similarly lowered the rate of TDZ required for 75% stand reduction of velvetleaf in Trial 1 to 0.17 kg/ha in Maryland. Cool wet weather in Quebec contrasted with warm, dry weather in Maryland. Soybean biomass and yield were increased significantly by treatment with TDZ plus Cc in Trial 1 at both locations.

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

Journal of Biomedicine and Biotechnology ◽

10.1155/2010/142486 ◽

2010 ◽

Vol 2010 ◽

pp. 1-5 ◽

Cited By ~ 1

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.

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

Canadian Journal of Botany ◽

10.1139/b82-181 ◽

1982 ◽

Vol 60 (8) ◽

pp. 1423-1427 ◽

Cited By ~ 2

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.

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Morphometric Characteristics, Polyphenols and Ascorbic Acid Variation in Brassica oleracea L. Novel Foods: Sprouts, Microgreens and Baby Leaves

Agronomy ◽

10.3390/agronomy10060782 ◽

2020 ◽

Vol 10 (6) ◽

pp. 782 ◽

Cited By ~ 2

Author(s):

Maria Concetta Di Bella ◽

Agnieszka Niklas ◽

Stefania Toscano ◽

Valentina Picchi ◽

Daniela Romano ◽

...

Keyword(s):

Antioxidant Activity ◽

Ascorbic Acid ◽

Plant Growth ◽

Growth Stage ◽

Added Value ◽

Growth Stages ◽

Novel Food ◽

Main Compound ◽

Novel Foods ◽

Freeze Dried

In the present study, we investigated the content and profile of polyphenols (PPH), ascorbic acid (AA), the Folin–Ciocalteu index (FCI), and antioxidant activity (1,1-diphenyl-2-picrylhydrazyl (DPPH) and peroxyl radical (ROO)) variation during three different plant growth stages (sprouts, microgreens and baby leaves) of two broccoli types, the traditional Sicilian sprouting broccoli landrace (‘Broccolo Nero’) and the broccoli standard (‘Cavolo broccolo Ramoso Calabrese’), and the standard commercial cultivar of kale (‘Cavolo Lacinato Nero di Toscana’). All biomasses collected were freeze-dried for PPH, AA, FCI, DPPH and ROO analysis. The highest polyphenol content was observed for ‘Broccolo Nero’ (BN) and ‘Cavolo Broccolo Ramoso Calabrese’ (CR), and generally sprouts showed significantly higher values compared to the microgreens and the baby leaves. The AA, FCI, DDPH and ROO significantly vary with regards to the cultivar and the plant growth stage, showing interaction between the two experimental factors analyzed. The interaction detected showed higher values for the antioxidant traits of the proposed novel food, especially for the two broccoli cultivars in the sprout growth stage in comparison to the microgreens and baby leaves. Our results suggest that the antioxidant activity is partially dependent on kaempferol and apigenin. The PPH compounds showed the highest values of kaempferol and apigenin for ‘Broccolo nero’, whereas for the other two cultivars studied, only kaempferol was the main compound represented. The data acquired are of interest for increasing the healthy traits of the novel food proposed showing the contribution offered by the neglected LRs until now underutilized and at risk of extinction. The germplasm conserved in several world genebanks could support and diversify the organic vegetable items, providing us with added-value products for organic food supply chains.

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Developing Rainfall- and Temperature-Based Models to Describe Infection of Canola Under Field Conditions Caused by Pycnidiospores of Leptosphaeria maculans

Phytopathology ◽

10.1094/phyto-99-7-0879 ◽

2009 ◽

Vol 99 (7) ◽

pp. 879-886 ◽

Cited By ~ 15

Author(s):

Kaveh Ghanbarnia ◽

W. G. Dilantha Fernando ◽

Gary Crow

Keyword(s):

Plant Growth ◽

Growth Stage ◽

Leptosphaeria Maculans ◽

The Other ◽

Field Conditions ◽

Maximum Temperature ◽

Growth Stages ◽

Upper Limit ◽

Average Maximum ◽

Two Stages

Blackleg, also known as Phoma stem canker, caused by Leptosphaeria maculans (Phoma lingam), is one of the most serious diseases of canola worldwide. In this study, the mean disease severity (Ds) and incidence (Di) of canola cv. Westar plants infected at the cotyledon, three-leaf, and six-leaf stages by pycnidiospores of L. maculans were monitored in the greenhouse after infection of the plants under field conditions in two successive years and associated with meteorological data during infection time. Pearson's correlation coefficient showed that total rainfall per week (R) was significantly correlated to Ds on plants infected at the cotyledon, three-leaf, and six-leaf stages, and average maximum temperature per week (Tmax) only showed significant correlation with plants infected at the cotyledon and six-leaf stages. These results also indicated that there is correlation between Di and R for plants infected at all three growth stages. A nonlinear model was developed to evaluate the combined effects of R and Tmax on Ds. The best model comprised monomolecular function and β probability density function for plants infected at the above three growth stages. Parameters, including maximum potential for Ds at a given rainfall (dmax), rate of changes with respect to rainfall (k), constant of integration (B), maximum potential for Ds with respect to Tmax (e), rate of increase with increasing Tmax to optimum (n), and rate of decrease as Tmax increased and passed the optimum Tmax (p), were estimated for plants infected at the above three growth stages. The effect of plant growth stage was characterized by differences in the upper limit parameter a. This parameter was greater for the plants infected at the cotyledon stage than for plants infected at the other two stages. The estimate of parameter k was the same for the plants infected at the cotyledon and three-leaf stages. This parameter was much lower for the plants infected at the six-leaf stage compared with two other stages. The logistic model could describe the disease incidence with respect to R slightly better than the other two models in the plants infected at all three growth stages. Based on the model, upper-limit estimate (dmax) was ≈100, 94.4, and 88.8% in the plants infected at cotyledon, three-leaf, and six-leaf stages, respectively. Di increased until rainfall reached ≈18, 10, and 13 mm/week and became constant in the plants at cotyledon, three-leaf, and six-leaf stages, respectively. Effects of plant growth stage on the rate of change with respect to R (parameter k) were lower in the plants infected at cotyledon than at the other two stages. The accuracy of the nonlinear models suggests that they could be used to develop a comprehensive model to evaluate epidemics of blackleg based on pycnidiospores as sources of inoculum. However, additional years of data collection should improve model fit and evaluation of introduced models and contribute to the development of a more robust predictive model.

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Wheat Genotype, Early Plant Growth Stage and Infestation Density Effects on Russian Wheat Aphid (Homoptera: Aphididae) Population Increase and Plant Damage

Journal of Entomological Science ◽

10.18474/0749-8004-35.1.22 ◽

2000 ◽

Vol 35 (1) ◽

pp. 22-38 ◽

Cited By ~ 4

Author(s):

Nilsa A. Bosque-Pérez ◽

Dennis J. Schotzko

Keyword(s):

Plant Growth ◽

Growth Stage ◽

Initial Density ◽

Russian Wheat Aphid ◽

Reproductive Rate ◽

Diuraphis Noxia ◽

Population Increase ◽

Growth Stages ◽

Plant Damage ◽

Aphid Density

Population increase of the Russian wheat aphid, Diuraphis noxia (Mordvilko) (Homoptera: Aphididae), and its effect on early plant growth and damage were studied under laboratory conditions on two winter wheat genotypes, susceptible ‘Stephens’ and resistant 10085-5. Three early plant growth stages (one-, two-, and three-leaf stage), and three insect densities (0, 5 and 20 aphids per plant) were compared. Insect counts, plant damage assessments, plant height, leaf number and dry weight measurements were made. Diuraphis noxia population increase was greater on ‘Stephens’ than on 10085-5, but this was highly influenced by plant growth stage at time of infestation and initial aphid density. Host quality of ‘Stephens’ decreased rapidly when plants were infested at the 1 -left stage, especially with the high initial density (20 aphids), resulting in low aphid population increase. For all plant developmental stages and genotypes, D. noxia per capita population increase was lower at initial densities of 20 compared to 5 aphids per plant, probably due to a density-dependent reduction in reproductive rate associated with a reduction in host-plant quality and/or crowding. Diuraphis noxia significantly affected plant growth, but the magnitude of the effect was influenced by genotype. In general, susceptible ‘Stephens’ had significantly more damage and a greater reduction in growth than resistant 10085-5.

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Nonlinear Regressions for Analyzing Growth Stage and Quinclorac Interactions

Weed Technology ◽

10.1017/s0890037x00036447 ◽

1992 ◽

Vol 6 (4) ◽

pp. 898-903 ◽

Cited By ~ 34

Author(s):

William J. Chism ◽

Jeffrey B. Birch ◽

S. Wayne Bingham

Keyword(s):

Plant Growth ◽

Nonlinear Regression ◽

Growth Stage ◽

Dry Weight ◽

Weight Basis ◽

Growth Stages ◽

Growth Reduction ◽

True Leaf

Control of southern crabgrass by quinclorac was influenced by plant growth stage. A three-parameter nonlinear regression was used to describe the influence of quinclorac concentration on each growth stage and to compare growth stages. A SAS® program for these comparisons is described. Pseudo R2values for fit were above 0.98 for all tests. Flowering crabgrass plants had the highest GR50value (50% growth reduction on a dry weight basis) whereas preemergence, three- to five-true-leaf, and two- to four-tiller stages were lower.

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Herbicidal control of deathcamas (Zigadenus paniculatus)

Weed Technology ◽

10.1017/wet.2020.102 ◽

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.

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