Facilitation at early growth stages results in spatial associations and stable coexistence in late growth stages of two long‐lived, dominant shrubs

Experiments were conducted to study the effect of application rate, growth stage, and tank-mixing azimsulfuron or bentazon on the activity of cyhalofop, clefoxydim, and penoxsulam against two morphologically distinctEchinochloaspecies from rice fields in Greece. Mixtures of penoxsulam with MCPA were also evaluated. Cyhalofop (300 to 600 g ai/ha) applied at the three- to four-leaf growth stage provided 62 to 85% control of early watergrass but 41 to 83% control of late watergrass averaged over mixture treatments. Control ranged from 37 to 80% for early watergrass and from 35 to 78% for late watergrass when cyhalofop was applied at the five- to six-leaf growth stage averaged over mixture treatments. Mixtures of cyhalofop with azimsulfuron or bentazon reduced efficacy on both species irrespective of growth stage or cyhalofop application rate compared with cyhalofop alone. Clefoxydim (100 to 250 g ai/ha) applied alone at the three- to four-leaf growth stage provided 98 to 100% control of early watergrass and 91 to 100% control of late watergrass; when clefoxydim was applied alone at the five- to six-leaf growth stage the control obtained was 91 to 100% for early watergrass and 79 to 100% for late watergrass. Mixtures of clefoxydim with azimsulfuron or bentazon reduced efficacy on late watergrass at the early growth stage and on both species at the late growth stage. Penoxsulam (20 to 40 g ai/ha) applied alone provided 94 to 100% control of both species at both growth stages. Mixtures of MCPA with penoxsulam reduced efficacy on late watergrass at the early growth stage and on both species at the late growth stage. Mixtures of penoxsulam with azimsulfuron or bentazon reduced efficacy only on late watergrass at the late growth stage.

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Effect of Application Timing on Rhizome Johnsongrass (Sorghum halepense) Control with DPX-V9360

Weed Science ◽

10.1017/s0043174500056095 ◽

1990 ◽

Vol 38 (1) ◽

pp. 45-49 ◽

Cited By ~ 50

Author(s):

Timothy T. Obrigawitch ◽

William H. Kenyon ◽

Henry Kuratle

Keyword(s):

Growth Stage ◽

Field Studies ◽

Early Growth ◽

Effective Control ◽

Growth Stages ◽

Application Timing ◽

Leaf Surfaces ◽

Treated Leaf ◽

Plant Emergence ◽

Late Growth

Field, greenhouse, and laboratory studies were conducted to examine the effect of application timing on the activity of DPX-V9360 on rhizome johnsongrass. Field and greenhouse studies indicated that johnsongrass treated with postemergence applications of DPX-V9360 at late growth stages (>5 leaves) was controlled more effectively than when treated in early growth stages (<5 leaves). Johnsongrass control was optimized with split-postemergence applications (treatments applied at early and late growth stages) in field studies compared to a single postemergence application at either early or late growth stages. The pattern of translocation of 2-14C (pyrimidine)-labeled DPX-V9360 applied to a fully expanded johnsongrass leaf did not differ significantly between three different growth stages of 10-, 30-, and 60-cm height. Over 60% of the absorbed14C remained in the treated leaf. Most of the translocated14C moved out of the treated leaf within 3 days after application and distributed to the shoot in greater quantities than to the rhizomes. About 40% of14C-DPX-V9360 applied to the leaf surfaces of a tolerant species (corn) or susceptible species (johnsongrass) was absorbed into the leaf. Corn metabolized over 90% of absorbed DPX-V9360 within 20 h, while there was no perceptible metabolism of DPX-V9360 in johnsongrass leaves after 24 h. Late growth stage and split-postemergence applications appear to provide more effective control than early growth stage applications because of better control of regrowth (new shoot emergence from rhizomes after application) and because tillering and plant emergence are more nearly complete at application time.

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Multiplex conidium morphology in species of the Ulocladium atrum group

Canadian Journal of Botany ◽

10.1139/b98-091 ◽

1998 ◽

Vol 76 (9) ◽

pp. 1533-1539 ◽

Cited By ~ 1

Author(s):

Emory G Simmons

Keyword(s):

Key Words ◽

Daucus Carota ◽

Early Growth ◽

Species Group ◽

Growth Stages ◽

Daucus Carota L ◽

Late Growth

Cultures of many isolates of Ulocladium Preuss mature with conidium populations dominated by dark, obovoid to spherical, densely ornamented spores similar to those of typical Ulocladium atrum Preuss. Early-growth conidia of such isolates frequently are quite different morphologically from those of U. atrum and are considered to be useful in defining species within a U. atrum species group. Four species are compared from this viewpoint in both early-growth and late-growth stages: U. atrum, Ulocladium cucurbitae (Letendre & Roumeguère) Simmons, Ulocladium multiforme Simmons sp.nov. (from soil), and Ulocladium dauci Simmons sp.nov. (from seed of Daucus carota L.).Key words: Ulocladium, classification, conidium variability.

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Effects of simulated hail damage, and foliar-applied recovery treatments, on growth and grain yield of wheat, field pea and dry bean crops

Canadian Journal of Plant Science ◽

10.1139/cjps-2020-0231 ◽

2021 ◽

Author(s):

Gurbir Singh Dhillon ◽

Mike Gretzinger ◽

Lewis Baarda ◽

Ralph Lange ◽

Kabal Singh Gill ◽

...

Keyword(s):

Grain Yield ◽

Early Growth ◽

Kernel Weight ◽

Field Pea ◽

Crop Damage ◽

Yield Reduction ◽

Growth Stages ◽

Dry Bean ◽

Hail Damage ◽

Late Growth

Hailstorms can be responsible for significant economic loss to the agricultural sector in Alberta, Canada. Foliar applications of certain fungicides and nutrient blends have been advocated to promote recovery and yield of hail-damaged crops. Proper understanding of different crop and hail-related factors is required for an accurate assessment of hail damage to crops, and for evaluations of hail-recovery product claims. This study was undertaken at three locations in Alberta during three growing seasons (2016-18) to determine the effects of two levels of simulated hail severity at three different crop developmental stages including early growth (BBCH 30 for wheat; BBCH 14-16 for pulses), mid-growth (BBCH 39 for wheat; BBCH 60 for pulses) and late growth (BBCH 60 for wheat; BBCH 71 for pulses) stages. Plant growth, and yield parameters of wheat (Triticum aestivum L.), field pea (Pisum sativum L.) and dry bean (Phaseolus vulgaris L.) crops were measured. Simulated hail damage led to reductions in height, biomass, NDVI, grain yield and kernel weight of all three crops. Average yield decreased by 24 and 35% for wheat, 17 and 35% for dry beans, and 37 and 45% for field peas for light and heavy hail severity, respectively. Hail timing was a critical factor influencing the extent of crop damage, with hail damage during early growth stage leading to lesser yield reduction compared to hail damage at mid-growth and late growth stages. Fungicides and nutrient blends applications did not significantly improve crop recovery, grain yield or kernel weight for any of the crops in this study.

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Effect of Herbicides on the Management of the Invasive Weed Solanum rostratum Dunal (Solanaceae)

Plants ◽

10.3390/plants10020284 ◽

2021 ◽

Vol 10 (2) ◽

pp. 284

Author(s):

Jackline Abu-Nassar ◽

Maor Matzrafi

Keyword(s):

Growth Stage ◽

Late Summer ◽

Early Spring ◽

Growth Stages ◽

Weed Species ◽

Invasive Weed ◽

Solanum Rostratum ◽

Stage 4 ◽

Chemical Solutions ◽

Late Growth

Solanum rostratum Dunal is an invasive weed species that invaded Israel in the 1950s. The weed appears in several germination flashes, from early spring until late summer. Recently, an increase in its distribution range was observed, alongside the identification of new populations in the northern part of Israel. This study aimed to investigate the efficacy of herbicide application for the control of S. rostratum using two field populations originated from the Golan Heights and the Jezreel Valley. While minor differences in herbicide efficacy were recorded between populations, plant growth stage had a significant effect on herbicide response. Carfentrazone-ethyl was found to be highly effective in controlling plants at both early and late growth stages. Metribuzin, oxadiazon, oxyfluorfen and tembutrione showed reduced efficacy when applied at later growth stage (8–9 cm height), as compared to the application at an early growth stage (4–5 cm height). Tank mixes of oxadiazon and oxyfluorfen with different concentrations of surfactant improved later growth stage plant control. Taken together, our study highlights several herbicides that can improve weed control and may be used as chemical solutions alongside diversified crop rotation options. Thus, they may aid in preventing the spread and further buildup of S. rostratum field populations.

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Osmotic Stress or Ionic Composition: Which Affects the Early Growth of Crop Species More?

Agronomy ◽

10.3390/agronomy11030435 ◽

2021 ◽

Vol 11 (3) ◽

pp. 435

Author(s):

Agnieszka Ludwiczak ◽

Monika Osiak ◽

Stefany Cárdenas-Pérez ◽

Sandra Lubińska-Mielińska ◽

Agnieszka Piernik

Keyword(s):

Osmotic Stress ◽

Stress Responses ◽

Ionic Composition ◽

Degradation Process ◽

Early Growth ◽

Cultivated Plants ◽

C3 Plants ◽

Growth Stages ◽

Crop Species ◽

Ionic Salt

Salinization is a key soil degradation process. An estimated 20% of total cultivated lands and 33% of irrigated agricultural lands worldwide are affected by high salinity. Much research has investigated the influence of salt (mainly NaCl) on plants, but very little is known about how this is related to natural salinity and osmotic stress. Therefore, our study was conducted to determine the osmotic and ionic salt stress responses of selected C3 and C4 cultivated plants. We focused on the early growth stages as those critical for plant development. We applied natural brine to simulate natural salinity and to compare its effect to NaCl solution. We assessed traits related to germination ability, seedlings and plantlet morphology, growth indexes, and biomass and water accumulation. Our results demonstrate that the effects of salinity on growth are strongest among plantlets. Salinity most affected water absorption in C3 plants (28% of total traits variation), but plant length in C4 plants (17–27%). Compensatory effect of ions from brine were suggested by the higher model plants’ growth success of ca 5–7% under brine compared to the NaCl condition. However, trait differences indicated that osmotic stress was the main stress factor affecting the studied plants.

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Coastal Mangrove Response to Marine Erosion: Evaluating the Impacts of Spatial Distribution and Vegetation Growth in Bangkok Bay from 1987 to 2017

Remote Sensing ◽

10.3390/rs12020220 ◽

2020 ◽

Vol 12 (2) ◽

pp. 220 ◽

Cited By ~ 2

Author(s):

Han Xiao ◽

Fenzhen Su ◽

Dongjie Fu ◽

Qi Wang ◽

Chong Huang

Keyword(s):

Spatial Distribution ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Mangrove Ecosystem ◽

Early Growth ◽

Growth Stages ◽

Human Disturbances ◽

Vegetation Growth ◽

Two Parameters ◽

The Impact

Long time-series monitoring of mangroves to marine erosion in the Bay of Bangkok, using Landsat data from 1987 to 2017, shows responses including landward retreat and seaward extension. Quantitative assessment of these responses with respect to spatial distribution and vegetation growth shows differing relationships depending on mangrove growth stage. Using transects perpendicular to the shoreline, we calculated the cross-shore mangrove extent (width) to represent spatial distribution, and the normalized difference vegetation index (NDVI) was used to represent vegetation growth. Correlations were then compared between mangrove seaside changes and the two parameters—mangrove width and NDVI—at yearly and 10-year scales. Both spatial distribution and vegetation growth display positive impacts on mangrove ecosystem stability: At early growth stages, mangrove stability is positively related to spatial distribution, whereas at mature growth the impact of vegetation growth is greater. Thus, we conclude that at early growth stages, planting width and area are more critical for stability, whereas for mature mangroves, management activities should focus on sustaining vegetation health and density. This study provides new rapid insights into monitoring and managing mangroves, based on analyses of parameters from historical satellite-derived information, which succinctly capture the net effect of complex environmental and human disturbances.

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