Evaluating Sensitivity of Five Aquatic Plants to a Novel Arylpicolinate Herbicide Utilizing an Organization for Economic Cooperation and Development Protocol

Weed Science ◽  
2016 ◽  
Vol 64 (1) ◽  
pp. 181-190
Author(s):  
Michael D. Netherland ◽  
Robert J. Richardson

New arylpicolinate herbicide chemistry under development for rice, aquatic weed management, and other uses was evaluated using five aquatic plants. The herbicide 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)-5-fluoro-pyridine-2-benzyl ester—also identified as XDE-848 BE or SX-1552 (proposed International Organization for Standardization common name in review; active tradename RinskorTM)—and its acid form (XDE-848 acid or SX-1552A) were evaluated on three dicots: (1) Eurasian watermilfoil (EWM), (2) megalodonta, and (3) crested floating heart (CFH), and two monocots: (1) hydrilla and (2) elodea. A small-scale Organization for Economic Cooperation and Development (OECD) protocol developed using EWM for registration studies was utilized. EWM and megalodonta were also evaluated in larger-scale mesocosms for comparison. In-water concentrations between 0.01 and 243 μg ai L−1as SX-1552 or SX-1552A were applied under static conditions for 14 (growth chamber) or 28 d (mesocosm). EWM was susceptible to both SX-1552 and SX-1552A, with dry-weight 50% effective concentration (EC50) values of 0.11 and 0.23 μg ai L−1under growth chamber conditions. Megalodonta had EC50values of 11.3 and 14.5 μg ai L−1for the SX-1552 and SX-1552A. CFH was more sensitive to SX-1552 (EC50= 5.6 μg ai L−1) than to SX-1552A (EC50= 23.9 μg ai L−1). Hydrilla had EC50values of 1.4 and 2.5 μg ai L−1, whereas elodea was more tolerant, with EC50values of 6.9 and 13.1 μg ai L−1for SX-1552 and SX-1552A, respectively. For EWM mesocosm trials, EC50values for SX-1552 and 1552A were 0.12 μg ai L−1and 0.58 μg ai L−1, whereas the megalodonta EC50was 6.1 μg ai L−1. Activity of SX-1552 on EWM, hydrilla, and CFH merits continued investigation for selective aquatic weed control properties. Results suggest that the OECD protocol can be used to screen activity of herbicides for multiple aquatic plant species.

2021 ◽  
Author(s):  
Christopher Mudge ◽  
Kurt Getsinger

Herbicide selection is key to efficiently managing nuisance vegetation in our nation’s waterways. After selecting the active ingredient, there still remains multiple proprietary and generic products to choose from. Recent small-scale research has been conducted to compare the efficacy of these herbicides against floating and emergent species. Therefore, a series of mesocosm and growth chamber trials were conducted to evaluate subsurface applications of the following herbicides against submersed plants: diquat versus coontail (Ceratophyllum demersum L.), hydrilla (Hydrilla verticillata L.f. Royle), southern naiad (Najas guadalupensis (Sprengel) Magnus), and Eurasian watermilfoil (Myriophyllum spicatum L.); flumioxazin versus coontail, hydrilla, and Eurasian watermilfoil; and triclopyr against Eurasian watermilfoil. All active ingredients were applied at concentrations commonly used to manage these species in public waters. Visually, all herbicides within a particular active ingredient performed similarly with regard to the onset and severity of injury symptoms throughout the trials. All trials, except diquat versus Eurasian watermilfoil, resulted in no differences in efficacy among the 14 proprietary and generic herbicides tested, and all herbicides provided 43%–100% control, regardless of active ingredient and trial. Under mesocosm and growth chamber conditions, the majority of the generic and proprietary herbicides evaluated against submersed plants provided similar control.


1993 ◽  
Vol 28 (10) ◽  
pp. 207-213 ◽  
Author(s):  
B. G. Yeoh

Water hyacinth (Eichhornia crassipes) was found to be useful in enhancing the final discharge quality of some agroindustrial wastewaters treated in lagoon systems. With a hydraulic retention time (HRT) of 5 days, the macrophyte was able to further reduce the biochemical oxygen demand (BOD) of anaerobically and aerobically treated palm oil mill effluent by 40% to 50 mgl-1, accompanied by remarkable removal of ammoniacal nitrogen (AN) and total kjeldahl nitrogen (TKN) by 53.7% and 68.8% respectively. It also assisted in the settling of suspended solids (SS) to below 20 mgl-1. In the secondary treatment of small-scale piggery effluent, the aquatic weed was found in a pilot field investigation to be 17-112% more efficient than algae in removing BOD and COD loads from a reconstituted effluent. A study at an institutional farm confirmed that >97% reduction of the major pollutional parameters was achieved. Introduction of hyacinth to a pilot plant treating sugar refinery wastewater resulted in the removal of BOD, COD and SS by 43.5%, 35.8% and 21.9% respectively with a HRT of 7 days. However, a chloride content exceeding 100 mgl-1 would inhibit its healthy growth. In the tertiary treatment of natural rubber processing effluent, removals of 85% BOD, 80% COD, 88% SS, 50% AN and 53% TKN were achieved with a HRT of 10 days. Increasing the HRT to 15 days resulted in higher removal efficiencies. Harvesting data indicated that the average biomass produced was 6-10% per day. The average growth rate of the aquatic plant could be as high as 505kg ha-1day-1 on dry weight basis.


1989 ◽  
Vol 31 (6) ◽  
pp. 479-486 ◽  
Author(s):  
Stella D. Elakovich

2015 ◽  
Vol 45 (9) ◽  
pp. 1557-1563 ◽  
Author(s):  
Guilherme Vestena Cassol ◽  
Luis Antonio de Avila ◽  
Carla Rejane Zemolin ◽  
Andrey Piveta ◽  
Dirceu Agostinetto ◽  
...  

<p>Dose-response experiments were carried out to evaluate the sensitivity of imidazolinone-resistant red rice to nonselective herbicides currently used in rice-soybean rotation in Rio Grande do Sul. Two red rice biotypes previously identified as resistant and susceptible to the imidazolinone herbicides were treated with imazapic plus imazapic, glyphosate and glufosinate under nine herbicide rates. A non-linear log-logistic analysis was used to estimate the herbicide rate that provided 50% red rice control and dry weight reduction (GR<sub>50</sub>). Imidazolinone-resistant red rice exhibited greater GR<sub>50</sub> values than imidazolinone-susceptible biotype for imazapyr plus imazapic. In contrast, both imidazolinone-resistant and susceptible red rice showed similar GR<sub>50</sub>values for glyphosate and glufosinate. These results indicate that glyphosate and glufosinate effectively control imidazolinone-resistant red rice at similar herbicide rates used to control imidazolinone-susceptible; however, integrated weed management practices must be adopted in rice-soybean rotation to delay resistance evolution of red rice populations to glyphosate and glufosinate</p>


2015 ◽  
Vol 66 (10) ◽  
pp. 857 ◽  
Author(s):  
James Prescott ◽  
Shijie Zhou ◽  
Andhika P. Prasetyo

Tropical sea cucumbers are commonly exploited by small-scale, poorly managed fisheries. A fundamental problem in managing sea cucumber fisheries is the lack of basic knowledge of important life history characteristics for most species. As a result of plastic body dimensions, biological research on this group of animals becomes exceptionally challenging. To improve our understanding of essential biological parameters, we conducted a study to investigate correlations among various body measurements. We analysed a total of 18 sea cucumber species and more than 6600 individuals collected at Scott Reef in the Timor Sea, north-west Australia. We used hierarchical Bayesian errors-in-variables models to specifically take into account measurement errors that are obviously unavoidable. The measures included three types of weights (wet weight, gutted weight and dry weight) and two body dimensions (length and width). The modelling reveals that using both body length and width as independent variables, wet weight increases approximately linearly with body length, but is a power function (~1.6) of body width, although variability exists among species. Dry weight tends to increase more slowly with body length, but has a similar power function of body width. Linear relationships are established between the three types of weights. On average, ~11% of a live specimen and ~16% of a gutted specimen is processed to the commercially traded dry body wall. Our results can be applied to sea cucumbers in other areas and can be useful for data standardisation and size-based fisheries management.


2017 ◽  
Vol 70 (3) ◽  
Author(s):  
Ichsan Nurul Bari ◽  
Hisashi Kato-Noguchi

Exploration of allelochemicals with phytotoxic effects is intended to minimize a current dependency on synthetic herbicides in weed management. Several allelochemicals from the tropical tree <em>Cerbera manghas</em> (sea mango) have been reported as termiticides and bactericides. The present study investigated possible phytotoxic effects of <em>C. manghas</em> leaf extracts under laboratory conditions. Four monocots: barnyard grass (<em>Echinochloa crus-galli</em>), foxtail fescue (<em>Vulpia myuros</em>), Italian ryegrass (<em>Lolium multiflorum</em>), and timothy (<em>Phleum pratense</em>) and four dicots: alfalfa (<em>Medicago sativa</em>), garden cress (<em>Lepidium sativum</em>), lettuce (<em>Lactuca sativa</em>), and rapeseed (<em>Brassica napus</em>) were used as test species. Elongation of both shoots and roots of seedlings was measured to assess any phytotoxic effects. The results showed that the sensitivities of shoots and roots were different between the test species, and the inhibition of seedling elongation significantly increased with increasing concentration of leaf extracts of <em>C. manghas</em> for all the test species. The IC<sub>50</sub> (50% inhibitory concentration) values showed that 8.50–32.30 and 4.26–34.67 mg dry weight equivalent extract mL<sup>−1</sup> of <em>C. manghas</em> inhibited seedling elongation by 50%, for shoots and roots respectively. Isolation and identification of the phytotoxic substances from <em>C. manghas</em> are suggested for future investigation.


2015 ◽  
Vol 6 ◽  
pp. 129-138
Author(s):  
A O Edeoja ◽  
A O Owolabi

Water hyacinth is the world's worst water weed that is responsible for many environmental and economical problems. Nigerian fresh waters have been infested with this aquatic weed. In this work, a Natural Convection Mixed Mode Solar Dryer for drying water hyacinth to about 10% of its moisture content was constructed and tested as a component of controlling its infestation of the River Benue. The performance of the dryer was compared with the traditional open–air sun drying as the control for drying water hyacinth in Makurdi, Benue State Nigeria. The water hyacinth was dried for 8 hours each day for 4 days. 500g of water hyacinth on wet basis was dehydrated by about 437g on dry basis in 20 hours in the dryer while the control required 32 hours. The dryer was found to be technically more suitable for drying water hyacinth both in terms of the drying rate and quality of the dried product.


2021 ◽  
Vol 23 (2) ◽  
pp. 121-128
Author(s):  
Advent F. Sitanggang ◽  
Marulak Simarmata ◽  
Bilman Wilman Simanihuruk ◽  
Uswatun Nurjanah

[ALLELOCHEMICAL POTENTIAL OF AQUEOUS EXTRACT AND MULCH OF PLANT BIOMASS OF SORGHUM (Sorgum bicolor L. Moench)]. This study was aimed to examine the allelopathic potential of sorghum through aqueous extract and mulch from biomass on seed germination and early growth of three tested plants, namely rice, mustard and cucumber. The results showed that the aqueous extract of the sorghum biomass significantly inhibited the germination of mustard and cucumber seeds, reduced the vigor-index of the germination of rice, mustard and cucumber seeds, and suppressed the growth of radicle length of mustard sprouts. The same thing was seen when sorghum biomass was tested as mulch which also suppressed the early growth of the tested plants on the variables of stem height, fresh and dry weight of biomass of rice, mustard and cucumber. The higher the concentration of allelochemicals extract or sorghum mulch, the stronger the inhibition on germination and early growth of the three test plants. At a concentration of 10% allelochemicals suppressed the germination of mustard and cucumber to 76 and 79%, respectively, while a dose of 10% mulch suppressed early growth in the height of rice, mustard, and cucumber to 56, 55, and 68%; and dry weight to 53, 30 and 60%. The results of this study are important information about the allelochemical potential of sorghum as a natural herbicide in integrated weed management


Author(s):  
B. Sandhya Rani ◽  
V. Chandrika ◽  
G. Prabhakara Reddy ◽  
P. Sudhakar ◽  
K.V. Nagamadhuri ◽  
...  

Background: Maize followed by summer pulses is the emerging cropping system in many places in India. Herbicides are the efficient tools for checking weed infestation and their usage is increasing throughout the globe due to increased labour cost and quick weed control. Some herbicides do not degrade quickly and may remain in the soil for weeks, months or years after application and may inhibit the growth of succeeding crops. Methods: Field experiment was conducted in a randomized block design (RBD) during rabi and summer seasons of 2017-18 and 2018-19 to know the residual effect of different herbicides applied in maize on succeeding greengram. Result: The present study revealed that lower density and dry weight of total weeds and higher yield attributes and yield was recorded with the practice of adopting two hand weedings at 15 and 30 DAS, which was however, at par with atrazine 1.0 kg ha-1 as PE fb one HW at 30 DAS, atrazine 1.0 kg ha-1 as PE fb topramezone 30 g ha-1 as PoE and atrazine 1.0 kg ha-1 as PE fb tembotrione 120 g ha-1 as PoE, without any significant disparity among them. Herbicides applied in maize did not alter statistically the enzyme activity and microbial count in the soil at harvest of succeeding greeengram. 


Sign in / Sign up

Export Citation Format

Share Document