scholarly journals Activity of the Recommended and Optimized Rates of Pyridate on Chickpea - Mesorhizobium mediterraneum Symbiosis

2014 ◽  
Vol 6 (1) ◽  
pp. 92-98 ◽  
Author(s):  
Mehdi PARSA ◽  
Akbar ALIVERDI ◽  
Hossein HAMMAMI

Crop-rhizobium symbiosis can be influenced by leaching of herbicides which is unavoidable after their application. Due to an adjuvant which might help to develop the low-use-rate of herbicide, an experiment was carried out to compare the impact of the recommended rate (1200 g active ingredient ha-1) and the optimized rate (282.15 g active ingredient ha-1) of pyridate on the biological properties of eight chickpea cultivars inoculated with Mesorhizobium mediterraneum, grown in pots. Based on the required rate of herbicide to give 95% control of common lambsquarters (Chenopodium album L.) value, the efficacy of pyridate improved up to 3.87-fold by adding methylated rapeseed oil to spray solution. The ‘Desi’ cultivar had significantly higher nodulation than ‘Kabuli’ cultivar. In general, toxicity of the recommended rate was higher than the optimized rate. With the exception of root dry weight, all of the measured parameters were significantly affected by the recommended rate of pyridate in varying degrees. The symbiotic properties of chickpea cultivars were affected more than 10% at the recommended dose. The reduced nodulation ranged from 29% to 73% among cultivars exposed to pyridate at the recommended dose. The ‘Desi’ cultivar was more sensitive than the ‘Kabuli’ to the recommended rate of pyridate. We may conclude that effective low-use-rate of pyridate via applying of activator adjuvants should be noted.

Weed Science ◽  
1996 ◽  
Vol 44 (1) ◽  
pp. 1-6 ◽  
Author(s):  
David H. Ketel

Common lambsquarters was treated with metamitron (M) and glyphosate (G) to investigate chlorophyll content as a single, biological parameter for indicating sub-lethal-treated weeds. In three different greenhouse experiments the herbicides were applied at dose rates of 1/8, 1/4 and 1/2 times the M-recommended dose rate (= 0.7 kg ai ha−1), and 1/16, 1/8, and 1/4 times the G-recommended dose rate (= 1.44 kg ai ha−1), respectively. Three weeks after herbicide application the chlorophyll content in leaves of plants treated with 1/2 M was lower than the control. At the same time the chlorophyll content in leaves of plants treated with 1/8 and 1/4 M was higher than the control. The chlorophyll content in the leaves of plants treated with 1/16 and 1/8 G was also higher than the control, but the chlorophyll content in the leaves of plants treated with 1/4 G was equal to the control. A dose of 1/2 M killed 30% of available plants within 29 d, but most of the plants were still alive after 29 d when 1/4 M, 1/8 M, 1/4 G, 1/8 G and 1/16 G had been used. The fresh weight of the biomass reflected the fitness of the plants observed with time and was related to chlorophyll content. The dry weight of the biomass, however, was probably related to the typical action of metamitron and glyphosate. Measurements with a remote sensing technique supported the measurement of chlorophyll with a spectrophotometer confirming a significant discrepancy with time between a herbicide's affect on chlorophyll content and on plant growth. Because differences in chlorophyll content may have caused differences in the progress of plant degradation in sub-lethal- and lethal-treated plants, it is concluded that the chlorophyll content can be used as a single, biological parameter for indicating sub-lethal dose rates of metamitron and glyphosate.


Weed Science ◽  
1990 ◽  
Vol 38 (2) ◽  
pp. 113-118 ◽  
Author(s):  
S. Kent Harrison

Multiple regression and response surface plots were used to analyze the effects of common lambsquarters population density and interference duration on weed growth and soybean seed yield. Under favorable growing conditions in 1986, weed biomass production at all population densities and interference durations was four to five times that produced in 1987, under less favorable conditions. However, there was no significant treatment by year interaction for soybean seed yield reduction by common lambsquarters, and production of each kg/ha weed biomass resulted in an average soybean yield reduction of 0.26 kg/ha. Utilizing 5% yield loss as an arbitrary threshold level, the regression equation predicted a common lambsquarters density threshold of 2 plants/m of row for 5 weeks of interference after crop emergence and 1 plant/m of row for 7 weeks. Seed production by individual common lambsquarters plants was highly correlated (r=0.92) with weed dry weight, and seed production ranged from 30 000 to 176 000 seeds/plant.


Weed Science ◽  
2008 ◽  
Vol 56 (5) ◽  
pp. 685-691 ◽  
Author(s):  
Andrew M. Westhoven ◽  
Greg R. Kruger ◽  
Corey K. Gerber ◽  
Jeff M. Stachler ◽  
Mark M. Loux ◽  
...  

Biotypes of common lambsquarters with tolerance to glyphosate have been identified in a number of states, but little is known about their fitness characteristics. Field and greenhouse studies were conducted to characterize the response of selected glyphosate-tolerant common lambsquarters biotypes to glyphosate, and also their biological and reproductive characteristics. In a greenhouse dose-response study, GR50and GR90values for four tolerant biotypes ranged from 1.48 to 3.22 and 8.73 to 18.7 kg ae ha−1, respectively, compared to 0.57 and 2.39 kg ae ha−1, respectively, for a glyphosate-sensitive biotype. In a field dose-response study, the GR50and GR90values were 0.06 and 0.48 kg ae ha−1, respectively, for a tolerant biotype, compared to 0.036 and 0.19 kg ae ha−1, respectively, for the sensitive biotype. The growth rate, time until flowering, and seed production of eight tolerant and two sensitive biotypes was evaluated in a field study. The tolerant biotypes grew taller, amassed more leaf area and dry weight, and advanced through growth stages more rapidly than sensitive biotypes during the early portion of the growing season. The tolerant biotypes were taller than sensitive biotypes at 6 and 10 wk after transplanting, but had lower dry weight at maturity. Tolerant biotypes initiated flower primordia approximately 6 to 8 wk after transplanting, whereas sensitive biotypes required 12 wk. However, no apparent fitness penalties were observed in glyphosate-tolerant biotypes based on seed-production estimates.


2010 ◽  
Vol 58 (2) ◽  
pp. 123-132 ◽  
Author(s):  
G. Wágner ◽  
E. Nádasy

Based on the results of earlier greenhouse tests, a field experiment was conducted to evaluate the effects of three different herbicide combinations (clomazone, flumioxazine and pendimethaline combined with bentazone) at increasing nitrogen levels on the nitrogen uptake of green pea and common lambsquarters ( Chenopodium album L.). Nitrogen was administered to the pea plants in the form of ammonium nitrate at increasing levels: 0, 100, 200 and 300 kg/ha. The experimental soil was loamy Ramann’s brown forest soil (Eutric Cambisol). Green peas were grown to green maturity and harvested according to standard agricultural practices. Following harvest, the fresh and dry weight of the pea and weed shoots were recorded. The nitrogen, phosphorus and potassium contents were determined from dried plant samples after digestion with concentrated sulphuric acid.The main results can be summarized as followsThe addition of nitrogen to the treatments considerably altered the growing potential of pea plants, especially at the early growth stage, where an increase in dry biomass of nearly 30% was observed. Yield biomass decreased in the nitrogen treatments. The nitrogen concentration, which increased in every treatment, was directly correlated to the addition of nitrogen fertilizer. Herbicides mainly influenced the vegetative growth of the plants. Pendimethalin and flumioxazin indirectly caused an increase in the dry biomass of the shoots by killing the surrounding weeds.


2016 ◽  
Vol 30 (2) ◽  
pp. 573-586 ◽  
Author(s):  
Cody F. Creech ◽  
Jesaelen G. Moraes ◽  
Ryan S. Henry ◽  
Joe D. Luck ◽  
Greg R. Kruger

Herbicide applications often do not reach their full potential because only a small amount of the active ingredients reaches the intended targets. Selecting the appropriate application parameters and equipment can allow for improved efficacy. The objective of this research was to evaluate the effect of droplet size on efficacy of six commonly used herbicides. Atrazine (1.12 kg ai ha−1), cloransulam-methyl (0.18 g ai ha−1), dicamba (0.14 kg ae ha−1), glufosinate (0.59 kg ai ha−1), saflufenacil (12.48 g ai ha−1), and 2,4-D (0.20 kg ae ha−1) were applied to seven plant species using an XR11003 nozzle at 138, 276, and 414 kPa and a AI11003 nozzle at 207, 345, and 483 kPa. Each herbicide, nozzle, and pressure combination was evaluated for droplet size spectra. Treatments were applied at 131 L ha−1to common lambsquarters, common sunflower, shattercane, soybean, tomato, velvetleaf, and volunteer corn. Control from 2,4-D was observed to increase approximately 12% on average for all species except common lambsquarters as droplet size increased from medium to very coarse (Dv0.5303 to 462 μm;Dv0.5is droplet size such that 50% of spray volume is contained in droplets of equal or smaller size). Control with atrazine was near 95% for common lambsquarters, common sunflower, and soybean. Atrazine provided the greatest shattercane control using a medium (Dv0.5325 μm) droplet, whereas the same droplet size provided the lowest tomato control. Control of common lambsquarters, shattercane, and tomato with cloransulam-methyl increased 79% when decreasing droplet size from extremely coarse to fine (Dv0.5637 to 228 μm). Dicamba control of common lambsquarters increased 17% using a medium droplet compared with a fine droplet (Dv0.5279 to 204 μm). Dry weight of common sunflower and soybean was reduced 21% using dicamba when using a very coarse spray compared with a fine spray classification (Dv0.5491 to 204 μm). Common lambsquarters control using glufosinate increased 18% using a fine spray classification (Dv0.5186 μm) compared with medium (Dv0.5250 μm) and both very coarse droplet sizes (Dv0.5470 and 516 μm). Conversely, tomato and velvetleaf control with glufosinate was maximized using a very coarse (Dv0.5470 and 516 μm) or extremely coarse droplet (Dv0.5628 μm) with increases of 11 and 25% compared with a fine spray (Dv0.5186 μm). Saflufenacil control of volunteer corn was 38% greater using extremely coarse droplets (Dv0.5622 μm) than fine, medium, and very coarse spray classifications (Dv0.5257 to 514 μm). Overall, spray classifications for the herbicides evaluated play an important role in herbicide efficacy and should be tailored to the herbicide being used and the targeted weed species.


Weed Science ◽  
1984 ◽  
Vol 32 (1) ◽  
pp. 76-83 ◽  
Author(s):  
Edward E. Schweizer ◽  
Robert L. Zimdahl

The impact of two weed management systems on the weed seed reserves of the soil, on the yearly weed problem, and on corn (Zea maysL.) production was assessed where corn was grown under furrow irrigation for 6 consecutive years. In one system, 2.2 kg/ha of atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine] was applied annually to the same plots as a preemergence treatment. In the other system, a mixture of 1.7 kg/ha of atrazine plus 2.2 kg/ha of alachlor [2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide] was applied preemergence, followed by a postemergence application of 0.6 kg/ha of the alkanolamine salts of 2,4-D [(2,4-dichlorophenoxy)acetic acid]. The response of weeds and corn is presented only where atrazine was applied annually because the results were similar between both weed management systems. Weed seeds from eight annual species were identified, with redroot pigweed (Amaranthus retroflexusL. ♯ AMARE) and common lambsquarters (Chenopodium album♯ CHEAL) comprising 82 and 12%, respectively, of the initial 1.3 billion weed seeds/ha that were present in the upper 25 cm of the soil profile. After the sixth cropping year, the overall decline in the total number of redroot pigweed and common lambsquarters seeds was 99 and 94%, respectively. Very few weeds produced seeds during the first 5 yr, and no weed seeds were produced during the sixth year where atrazine was applied annually. When the use of atrazine was discontinued on one-half of each plot at the beginning of the fourth year, the weed seed reserve in soil began to increase due to an increase in the weed population. After 3 yr of not using atrazine, the weed seed reserve in soil had built up to over 648 million seeds/ha, and was then within 50% of the initial weed seed population. In the fifth and sixth years, grain yields were reduced 39 and 14%, respectively, where atrazine had been discontinued after 3 yr.


1999 ◽  
Vol 13 (3) ◽  
pp. 504-509 ◽  
Author(s):  
Prasanta C. Bhowmik ◽  
Sanjay Kushwaha ◽  
Sowmya Mitra

Greenhouse and field experiments were conducted to determine the response of corn (Zea mays), barnyardgrass (Echinochloa crus-galli), common lambsquarters (Chenopodium album), large crabgrass (Digitaria sanguinalis), velvetleaf (Abutilon theophrasti), and yellow foxtail (Setaria lutescence) to RPA 201772. Barnyardgrass, large crabgrass, velvetleaf, and common lambsquarters were more susceptible than yellow foxtail to RPA 201772. Velvetleaf was the most susceptible species and rates above 18 g ai/ha of RPA 201772 controlled 100% of the population 4 wk after treatment (WAT). Percent control of all the weed species increased with increased RPA 201772 rates. In the field, the dry weights of yellow foxtail decreased as the rate of RPA 201772 increased from 0 to 210 g/ha. However, a 60% reduction of dry weight of yellow foxtail was recorded at 140 g/ha of RPA 201772 compared to the untreated check 6 WAT, whereas at 12 WAT the dry weight of yellow foxtail was reduced to only 15% because of intraspecific competition. Yellow foxtail was moderately susceptible to RPA 201772. Corn was tolerant to RPA 201772; the GR80 value was 435 g/ha in the greenhouse. The bleaching injury to corn in the field was less than 10%, and it was found only with the 210 g/ha rate of RPA 201772. This injury was temporary and the plants recovered within 2 to 3 wk. Based on the GR80 values, velvetleaf was the most susceptible, followed by common lambsquarters, large crabgrass, barnyardgrass, and yellow foxtail.


1988 ◽  
Vol 2 (4) ◽  
pp. 505-508 ◽  
Author(s):  
Prasanta C. Bhowmik ◽  
Krishna N. Reddy

Field studies were conducted in 1982 to 1984 to determine the effects of common lambsquarters on growth, yield, and nutrient concentration of transplanted tomato. Common lambsquarters densities ranged from 16 to 64 plants/m tomato row and fresh weight ranged from 26 360 kg/ha at 16 plants/m to 46 000 kg/ha at 64 plants/m row. Common lambsquarters did not affect tomato shoot dry weight at the vegetative stage but decreased the weight at the early fruit stage. Season-long interference of common lambsquarters reduced marketable tomato fruit number and also, marketable fruit weight ranging from 17% at 16 plants/m to 36% to 64 plants/m row. Concentrations of N in tomato leaves were unaltered at vegetative and flowering stages but decreased regardless of common lambsquarters density at early fruit and harvest stages. Weed density did not alter concentrations of P, K, and Ca in tomato leaves.


Weed Science ◽  
1990 ◽  
Vol 38 (4-5) ◽  
pp. 358-364 ◽  
Author(s):  
Teresa M. Crook ◽  
Karen A. Renner

Field studies were conducted in 1987 and 1988 to evaluate the control and competitiveness of common lambsquarters in soybeans when present at four densities and when removed at four time intervals. Common lambsquarters were removed by hand or treated with a postemergence herbicide application of bentazon plus acifluorfen. Common lambsquarters could remain 10 weeks following soybean emergence before a 20% soybean yield reduction occurred when weeds were removed by hand. When treatment was attempted with postemergence herbicides, a 20% yield reduction occurred in 1987 if application was not made prior to 5 weeks after emergence. In 1988, all postemergence herbicide applications failed to control lambsquarters due to drought conditions. The postemergence herbicide's degree of control was reflected in the number of remaining lambsquarters plants. Common lambsquarters seed production and germination was not influenced by postemergence herbicide application. There was a strong correlation between dry weight of uncontrolled common lambsquarters plants and seed produced per plant.


Weed Science ◽  
1996 ◽  
Vol 44 (3) ◽  
pp. 517-522 ◽  
Author(s):  
Robert J. Parks ◽  
William S. Curran ◽  
Gregory W. Roth ◽  
Nathan L. Hartwig ◽  
Dennis D. Calvin

Biological fitness and negative cross-resistance to other herbicides may be an important factor in managing triazine-resistant common lambsquarters. Greenhouse experiments examined the sensitivity of a resistant and a susceptible biotype to foliarly-applied bentazon, bromoxynil, dicamba, pyridate, and thifensulfuron. The noncompetitive vigor of triazine-resistant and susceptible common lambsquarters also was compared by growing plants in individual containers and harvesting them periodically throughout their vegetative period and at reproductive maturity. In the herbicide susceptibility study, 11 kg ai ha−1atrazine had no effect on the growth of the resistant biotype, while it reduced susceptible common lambsquarters’ biomass by up to 68%. Estimated I50values indicated the resistant biotype exhibited between 36 and 79% greater susceptibility to bentazon, bromoxynil, dicamba, and pyridate than did the susceptible one, while both responded similarly to thifensulfuron. In growth studies, the susceptible biotype achieved greater height, leaf area, and plant dry weight than the resistant population for the majority of harvest dates; however, values equalized between biotypes as the plants reached maturity. These experiments suggest that alternative management programs that exploit reduced fitness and increased herbicide susceptibility in triazine-resistant common lambsquarters could be developed. However, further studies are needed to determine whether these results have application for the management of triazine-resistant weeds in the field.


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