Transport and redistribution of nitrogen at late growth stages in different oilseed rape cultivars

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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RNAi efficacy is enhanced by chronic dsRNA feeding in pollen beetle

Communications Biology ◽

10.1038/s42003-021-01975-9 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Jonathan Willow ◽

Liina Soonvald ◽

Silva Sulg ◽

Riina Kaasik ◽

Ana Isabel Silva ◽

...

Keyword(s):

Rna Interference ◽

Pest Management ◽

Oilseed Rape ◽

Growth Stages ◽

Short Term ◽

Pollen Beetle ◽

Brassicogethes Aeneus ◽

Crop Growth Stages ◽

Insecticidal Compounds ◽

Significant Mortality

AbstractDouble-stranded RNAs (dsRNAs) represent a promising class of biosafe insecticidal compounds. We examined the ability to induce RNA interference (RNAi) in the pollen beetle Brassicogethes aeneus via anther feeding, and compared short-term (3 d) to chronic (17 d) feeding of various concentrations of dsRNA targeting αCOP (dsαCOP). In short-term dsαCOP feeding, only the highest concentration resulted in significant reductions in B. aeneus survival; whereas in chronic dsαCOP feeding, all three concentrations resulted in significant mortality. Chronic dsαCOP feeding also resulted in significantly greater mortality compared to short-term feeding of equivalent dsαCOP concentrations. Our results have implications for the economics and development of dsRNA spray approaches for managing crop pests, in that multiple lower-concentration dsRNA spray treatments across crop growth stages may result in greater pest management efficacy, compared to single treatments using higher dsRNA concentrations. Furthermore, our results highlight the need for research into the development of RNAi cultivars for oilseed rape protection, given the enhanced RNAi efficacy resulting from chronic, compared to short-term, dsRNA feeding in B. aeneus.

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

Oikos ◽

10.1111/oik.08603 ◽

2021 ◽

Author(s):

Benjamin Schlau ◽

Travis Huxman ◽

Kailen Mooney ◽

Jessica Pratt

Keyword(s):

Early Growth ◽

Growth Stages ◽

Spatial Associations ◽

Stable Coexistence ◽

Late Growth

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Physiological and Biochemical Characteristics in Flag Leaves of the C Liangyou Series of Hybrid Rice Combinations at Late Growth Stages

Rice Science ◽

10.1016/s1672-6308(09)60033-0 ◽

2010 ◽

Vol 17 (4) ◽

pp. 319-325 ◽

Cited By ~ 3

Author(s):

Wen-bang TANG ◽

Gui-lian ZHANG ◽

Ying-hui XIAO ◽

Hua-bing DENG ◽

Ke FAN ◽

...

Keyword(s):

Hybrid Rice ◽

Growth Stages ◽

Biochemical Characteristics ◽

Flag Leaves ◽

Physiological And Biochemical Characteristics ◽

Physiological And Biochemical ◽

Late Growth

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Growth Regulator Herbicides Prevent Invasive Annual Grass Seed Production

Invasive Plant Science and Management ◽

10.1614/ipsm-d-09-00007.1 ◽

2010 ◽

Vol 3 (1) ◽

pp. 12-16 ◽

Cited By ~ 18

Author(s):

Matthew J. Rinella ◽

Marshall R. Haferkamp ◽

Robert A. Masters ◽

Jennifer M. Muscha ◽

Susan E. Bellows ◽

...

Keyword(s):

Plant Growth ◽

Seed Production ◽

Growth Regulators ◽

Growth Regulator ◽

Cereal Crops ◽

Growth Stages ◽

Internode Elongation ◽

Annual Grass ◽

Stages Of Growth ◽

Late Growth

AbstractAuxinic herbicides, such as 2,4-D and dicamba, that act as plant growth regulators are commonly used for broadleaf weed control in cereal crops (e.g., wheat, barley), grasslands, and noncroplands. If applied at late growth stages, while cereals are developing reproductive parts, the herbicides can reduce seed production. We tested whether growth regulators have this same effect on the invasive annual grass Japanese brome. The herbicides 2,4-D, dicamba, and picloram were applied at typical field use rates to Japanese brome at various growth stages in a greenhouse. Picloram reduced seed production nearly 100% when applied at the internode elongation, boot, or heading stages of growth, whereas dicamba appeared to be slightly less effective and 2,4-D was much less effective. Our results indicate it may be possible to control Japanese brome by using growth regulator herbicides to reduce its seed production, thereby depleting its short-lived seed bank.

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In-Field Observation of Root Growth and Nitrogen Uptake Efficiency of Winter Oilseed Rape

Agronomy ◽

10.3390/agronomy10010105 ◽

2020 ◽

Vol 10 (1) ◽

pp. 105

Author(s):

Julien Louvieaux ◽

Antoine Leclercq ◽

Loïc Haelterman ◽

Christian Hermans

Keyword(s):

Root Growth ◽

Oilseed Rape ◽

Root Development ◽

Nitrogen Uptake ◽

Root Morphology ◽

Growth Stages ◽

Winter Oilseed Rape ◽

Nitrogen Uptake Efficiency ◽

Uptake Efficiency ◽

N Concentration

Field trials were conducted with two nitrogen applications (0 or 240 kg N ha−1) and three modern cultivars of winter oilseed rape (Brassica napus L.) previously selected from a root morphology screen at a young developmental stage. The purpose is to examine the relationship between root morphology and Nitrogen Uptake Efficiency (NUpE) and to test the predictiveness of some canopy optical indices for seed quality and yield. A tube-rhizotron system was used to incorporate below-ground root growth information. Practically, clear tubes of one meter in length were installed in soil at an angle of 45°. The root development was followed with a camera at key growth stages in autumn (leaf development) and spring (stem elongation and flowering). Autumn was a critical time window to observe the root development, and exploration in deeper horizons (36–48 cm) was faster without any fertilization treatment. Analysis of the rhizotron images was challenging and it was not possible to clearly discriminate between cultivars. Canopy reflectance and leaf optical indices were measured with proximal sensors. The Normalized Difference Vegetation Index (NDVI) was a positive indicator of biomass and seed yield while the Nitrogen Balance Index (NBI) was a positive indicator of above-ground biomass N concentration at flowering and seed N concentration at harvest.

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Photosynthetic Mechanisms of Metaxenia Responsible for Enlargement of Carya cathayensis Fruits at Late Growth Stages

Frontiers in Plant Science ◽

10.3389/fpls.2020.00084 ◽

2020 ◽

Vol 11 ◽

Author(s):

Ren Huang ◽

Yun Zhang ◽

Qixiang Zhang ◽

Jianqin Huang ◽

Heikki Hänninen ◽

...

Keyword(s):

Growth Stages ◽

Carya Cathayensis ◽

Late Growth

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Control of Early Watergrass (Echinochloa Oryzoides) and Late Watergrass (Echinochloa Phyllopogon) with Cyhalofop, Clefoxydim, and Penoxsulam Applied Alone and in Mixture with Broadleaf Herbicides

Weed Technology ◽

10.1614/wt-05-140.1 ◽

2006 ◽

Vol 20 (4) ◽

pp. 992-998 ◽

Cited By ~ 9

Author(s):

Christos A. Damalas ◽

Kico V. Dhima ◽

Ilias G. Eleftherohorinos

Keyword(s):

Growth Stage ◽

Leaf Growth ◽

Application Rate ◽

Early Growth ◽

Rice Fields ◽

Growth Stages ◽

Early Growth Stage ◽

Late Growth ◽

Echinochloa Phyllopogon

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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