Identification of Goosegrass (Eleusine indica) Biotypes Resistant to Preemergence-Applied Oxadiazon

Goosegrass biotypes from golf courses in Richmond, VA (CCV) and New Bern, NC (RB) historically treated with oxadiazon were identified as resistant compared to susceptible standard (PBU) based on comparisons of oxadiazon applied preemergence at increasing rates (0.03 to 2.24 kg ha-1). Oxadiazon at rates ≤ 2.24 kg ha-1rate did not prevent emergence of suspected resistant CCV and RB seedlings. PBU emergence was completely prevented at 0.14 kg ha-1. Based on percent seedling emergence relative to non-treated and percent above-ground biomass reduction relative to non-treated, the oxadiazon rate at which emergence would be reduced 50% (I50) or 90% (I90) ranged from 0.12 to 0.18 kg ha-1or 10.83 to 85.57 kg ha-1, respectively for suspected resistant CCV and RB, compared to 0.03 to 0.4 kg ha-1or 0.12 to 0.19 kg ha-1, respectively for susceptible standard PBU. Seedling emergence data predicted 7.9 and 3.0 times greater I90values for CCV and RB, respectively compared to biomass data. All three biotypes were completely controlled by preemergence applied labeled rates of prodiamine and indaziflam. This is the first peer-reviewed report of evolved weed resistance to oxadiazon.

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The effect of simulated winter warming spells on Canada fleabane [Conyza canadensis (L.) Cronq. var. canadensis] seeds and plants

Canadian Journal of Plant Science ◽

10.4141/cjps2013-302 ◽

2014 ◽

Vol 94 (5) ◽

pp. 963-969 ◽

Cited By ~ 3

Author(s):

E. Tozzi ◽

E. M. Lyons ◽

R. C. Van Acker

Keyword(s):

Seedling Emergence ◽

Great Majority ◽

Early Spring ◽

Winter Survival ◽

Conyza Canadensis ◽

Above Ground Biomass ◽

Southern Ontario ◽

Winter Warming ◽

Ground Biomass ◽

Winter Annual

Tozzi, E., Lyons, E. M. and Van Acker, R. C. 2014. The effect of simulated winter warming spells on Canada fleabane [Conyza canadensis (L.) Cronq. var. canadensis] seeds and plants. Can. J. Plant Sci. 94: 963–969. Experiments were establish at three sites in southern Ontario, Canada in 2009 and 2010 to determine the possible effect of winter warming spells applied in either January, February or March on seed, seedlings, or rosettes of Canada fleabane including effects on winter survival, fecundity, above-ground biomass, and flowering timing. Warming spells reduced survival of fall-established rosettes and fall established seedlings. Warming spells occurring late in winter (March) had a greater effect where March warming spells reduced the survival of rosettes and seedlings on average by 53% and 80%, respectively. In addition, overwintering Canada fleabane plants (rosettes or seedlings) exposed to warming spells flowered earlier (between 29 and 71 days earlier). This study also confirms that Canada fleabane seed has little or no dormancy and that the great majority of seed recruits (either in fall or spring) within a given season (between 84% and 93%). We also determined that timing of seed shed in the fall significantly affects the proportion of seedlings emerging either in the spring or fall with late shed favoring seed overwintering and spring seedling emergence. The results of this study suggest that winter warming spells, especially later in the winter (into early spring), may limit the success of Canada fleabane and in particular its success as a winter annual.

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Influence of Soil Arsenic Levels on Biomass Production and Relationship the Concentration of Arsenic between Rice Straw and Grain

Asian Journal of Soil Science and Plant Nutrition ◽

10.9734/ajsspn/2019/v5i230061 ◽

2019 ◽

pp. 1-10

Author(s):

Mosud Iqbal ◽

G. K. M. Mustafizur Rahman ◽

G. M. Panaullah ◽

Humayun Kabir ◽

Jatish Chandra Biswas

Keyword(s):

Rice Straw ◽

Soil Science ◽

Rice Grain ◽

Above Ground Biomass ◽

Ground Biomass ◽

Soil Arsenic ◽

Rice Genotypes ◽

Relationship Of ◽

The Relationship ◽

Biomass Reduction

Arsenic (As) contamination is widespread in Bangladesh. It can cause health hazards depending on consumption of foods grown on As contaminated soil. Two pot experiments were conducted at net house, Department of Soil Science, Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur to study the effect of As on above ground biomass of different rice genotypes and to determine the relationship of As concentration between rice grains and straw. Sixteen rice genotypes were grown in pots soils having 0, 20, 40 and 60 mg/kg As both in winter and wet seasons. Soil As levels reduced above ground biomass of rice by 8-65%. Above ground biomass reduction was the least in BRRI dhan47 with variable soil As levels. Total As concentrations in straw and grains increased with increasing soil As levels. Moreover, the concentration of As in rice grain was also increased with greater As concentration in straw. Grain to straw ratio of As concentration was lower at higher As concentration in straw. It is indicated that reduced movement of As from rice straw to grain take place when straw As concentration was high.

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Mitotic-Inhibiting Herbicide Response Variation in Goosegrass (Eleusine indica) with a Leu136-Phe Substitution in α-Tubulin

Weed Science ◽

10.1017/wsc.2021.65 ◽

2021 ◽

pp. 1-16

Author(s):

Eli C. Russell ◽

John M. Peppers ◽

Claudia Ann Rutland ◽

Jinesh Patel ◽

Nathan D. Hall ◽

...

Keyword(s):

Seedling Emergence ◽

Population Based ◽

Target Site ◽

Susceptible Population ◽

Eleusine Indica ◽

First Report ◽

Putting Green ◽

Response Variation ◽

Emergence Response ◽

Biomass Reduction

Abstract Dithiopyr and dinitroanilines are preemergence-applied, mitotic-inhibiting herbicides used to control goosegrass [Eleusine indica (L.) Gaertn.]) in turfgrass. A suspected resistant E. indica population was collected from a golf course putting green and was evaluated for possible resistance to dithiopyr and prodiamine. After dose-response evaluation, the α-tubulin gene was sequenced for known target-site mutations that have been reported to confer resistance to mitotic-inhibiting herbicides. A mutation was discovered that resulted in an amino acid substitution at position 136 from leucine to phenylalanine (Leu136-Phe). Previous research has indicated that Leu136-Phe does confer resistance to dinitroaniline herbicides. The level of resistance indicated by regression models and I50 values indicates that there is a 54.1-, 4.7-, >100-, and >100-fold resistance to dithiopyr, prodiamine, pendimethalin, and oryzalin, respectively when compared to the susceptible population based on seedling emergence response and 88.4-, 7.8-, >100-, and >100-fold resistance to dithiopyr, prodiamine, pendimethalin, and oryzalin, respectively when compared to the susceptible population based on biomass reduction response. This is the first report of less resistance to prodiamine compared to pendimethalin or oryzalin due to a target-site α-tubulin mutation and the first report of a target-site α-tubulin mutation associated with dithiopyr resistance.

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ESTIMATION OF ABOVE GROUND BIOMASS OF THE THREE SITES (GRAZED SITE, PROTECTED SITE AND SEED SOWN SITE) FOR COMPARING THEIR PRODUCTIVITY IN KASHMIR VALLEY

FLORA AND FAUNA ◽

10.33451/florafauna.v23i2pp259-262 ◽

2017 ◽

Vol 23 (2) ◽

Author(s):

AFSHAN ANJUM BABA ◽

SYED NASEEM UL-ZAFAR GEELANI ◽

ISHRAT SALEEM ◽

MOHIT HUSAIN ◽

PERVEZ AHMAD KHAN ◽

...

Keyword(s):

Protected Areas ◽

Aboveground Biomass ◽

Plant Biomass ◽

Summer Season ◽

Above Ground Biomass ◽

Spring Season ◽

Kashmir Valley ◽

Ground Biomass ◽

Maximum Value ◽

Protected Site

The plant biomass for protected areas was maximum in summer (1221.56 g/m2) and minimum in winter (290.62 g/m2) as against grazed areas having maximum value 590.81 g/m2 in autumn and minimum 183.75 g/m2 in winter. Study revealed that at Protected site (Kanidajan) the above ground biomass ranged was from a minimum (1.11 t ha-1) in the spring season to a maximum (4.58 t ha-1) in the summer season while at Grazed site (Yousmarag), the aboveground biomass varied from a minimum (0.54 t ha-1) in the spring season to a maximum of 1.48 t ha-1 in summer seasonandat Seed sown site (Badipora), the lowest value of aboveground biomass obtained was 4.46 t ha-1 in spring while as the highest (7.98 t ha-1) was obtained in summer.

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The climatic imprint of bimodal distributions in vegetation cover for western Africa

Biogeosciences ◽

10.5194/bg-13-3343-2016 ◽

2016 ◽

Vol 13 (11) ◽

pp. 3343-3357 ◽

Cited By ~ 4

Author(s):

Zun Yin ◽

Stefan C. Dekker ◽

Bart J. J. M. van den Hurk ◽

Henk A. Dijkstra

Keyword(s):

Land Cover ◽

Congo Basin ◽

Shortwave Radiation ◽

Mean Annual Precipitation ◽

Above Ground Biomass ◽

Precipitation Regime ◽

Ground Biomass ◽

Western Africa ◽

Precipitation Regimes ◽

Woody Cover

Abstract. Observed bimodal distributions of woody cover in western Africa provide evidence that alternative ecosystem states may exist under the same precipitation regimes. In this study, we show that bimodality can also be observed in mean annual shortwave radiation and above-ground biomass, which might closely relate to woody cover due to vegetation–climate interactions. Thus we expect that use of radiation and above-ground biomass enables us to distinguish the two modes of woody cover. However, through conditional histogram analysis, we find that the bimodality of woody cover still can exist under conditions of low mean annual shortwave radiation and low above-ground biomass. It suggests that this specific condition might play a key role in critical transitions between the two modes, while under other conditions no bimodality was found. Based on a land cover map in which anthropogenic land use was removed, six climatic indicators that represent water, energy, climate seasonality and water–radiation coupling are analysed to investigate the coexistence of these indicators with specific land cover types. From this analysis we find that the mean annual precipitation is not sufficient to predict potential land cover change. Indicators of climate seasonality are strongly related to the observed land cover type. However, these indicators cannot predict a stable forest state under the observed climatic conditions, in contrast to observed forest states. A new indicator (the normalized difference of precipitation) successfully expresses the stability of the precipitation regime and can improve the prediction accuracy of forest states. Next we evaluate land cover predictions based on different combinations of climatic indicators. Regions with high potential of land cover transitions are revealed. The results suggest that the tropical forest in the Congo basin may be unstable and shows the possibility of decreasing significantly. An increase in the area covered by savanna and grass is possible, which coincides with the observed regreening of the Sahara.

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Above-ground biomass estimation of Indian tropical forests using X band Pol-InSAR and Random Forest

Remote Sensing Applications Society and Environment ◽

10.1016/j.rsase.2020.100462 ◽

2021 ◽

Vol 21 ◽

pp. 100462

Author(s):

Sadhana Yadav ◽

Hitendra Padalia ◽

Sanjiv K. Sinha ◽

Ritika Srinet ◽

Prakash Chauhan

Keyword(s):

Random Forest ◽

Tropical Forests ◽

Biomass Estimation ◽

Above Ground Biomass ◽

Ground Biomass ◽

X Band

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Comparison of Capability of SAR and Optical Data in Mapping Forest above Ground Biomass Based on Machine Learning

Environmental Sciences Proceedings ◽

10.3390/iecg2020-07916 ◽

2020 ◽

Vol 5 (1) ◽

pp. 13

Author(s):

Negar Tavasoli ◽

Hossein Arefi

Keyword(s):

Machine Learning ◽

Carbon Stock ◽

Vegetation Indices ◽

Forest Biomass ◽

Principal Component ◽

Optical Data ◽

Above Ground Biomass ◽

Ground Biomass ◽

Texture Characteristics ◽

Sentinel 2

Assessment of forest above ground biomass (AGB) is critical for managing forest and understanding the role of forest as source of carbon fluxes. Recently, satellite remote sensing products offer the chance to map forest biomass and carbon stock. The present study focuses on comparing the potential use of combination of ALOSPALSAR and Sentinel-1 SAR data, with Sentinel-2 optical data to estimate above ground biomass and carbon stock using Genetic-Random forest machine learning (GA-RF) algorithm. Polarimetric decompositions, texture characteristics and backscatter coefficients of ALOSPALSAR and Sentinel-1, and vegetation indices, tasseled cap, texture parameters and principal component analysis (PCA) of Sentinel-2 based on measured AGB samples were used to estimate biomass. The overall coefficient (R2) of AGB modelling using combination of ALOSPALSAR and Sentinel-1 data, and Sentinel-2 data were respectively 0.70 and 0.62. The result showed that Combining ALOSPALSAR and Sentinel-1 data to predict AGB by using GA-RF model performed better than Sentinel-2 data.

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