Controlled Release Starch Granule Formulations Reduce Herbicide Leaching in Soil Columns

1992 ◽  
Vol 6 (2) ◽  
pp. 317-321 ◽  
Author(s):  
Rick A. Boydston

Experimental controlled release starch granules (CRSG) containing 5.3% a.i. (w/w) norflurazon or 6% a.i. (w/w) simazine retarded the leaching of both herbicides in loamy sand soil columns when compared to commercial formulations of norflurazon [80% (w/w) dry flowable] or simazine [90% (w/w) water dispersible granule]. Barley bioassays indicated norflurazon and simazine remained in the surface 0 to 2.5 cm of soil when applied as CRSG formulations and moved to a depth of 15 cm when applied as commercial dry formulations and leached with 6 cm of water. CRSG placed on pre-wetted soil columns began to release norflurazon by 7 d at 25 C or 14 d at 15 C, and subsequent leaching moved norflurazon beyond the top 2.5 cm of the soil column.

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 607
Author(s):  
Hesham M. Ibrahim ◽  
Abdulaziz G. Alghamdi

Limited water resources in arid and semi-arid regions require innovative management to maintain crop production while minimizing the amounts of water used for irrigation. We investigated the impact of the particle size of natural clinoptilolite zeolite (CZ) on water content (WC) and hydraulic properties of a loamy sand soil. WC was measured using 5TE sensors installed at five depths (10, 20, 30, 40, and 50 cm) in soil columns (7.4 cm ID, 56 cm length). Three sizes of macro- and nano-CZ particles (20, 2.0, and 0.2 µm) were added to the soil at an application rate of 1%. The columns were subject to 14 wetting/drying cycles from 24 February to 8 December 2020. The HYDRUS-1D model was used to simulate WC and soil water storage inside the soil columns. WC increased with the decreasing particle size of CZ, especially when columns were subject to long drying periods. The larger surface area and smaller pore size of CZ altered the pore-size distribution of the loamy sand soil and increased the amount of microporosity inside the soil system, leading to increased water retention. Available water and soil water storage were increased by 3.6–14.7% and 6.8–10.5%, respectively, with larger increases with the decrease in CZ particle size. Variations in infiltration rate and hydraulic conductivity were statistically significant only with the smallest CZ particle size, with a reduction of 25.6% and 19.3% compared to the control, respectively. The HYDRUS-1D model accurately simulated WC and soil water storage, with only slight overestimation of WC (2.4%) at depths ≤ 30 cm. The results suggest that, in light-textured soils, the application of CZ in the ultra-fine nanoparticle size would increase water-holding capacity and reduce hydraulic conductivity, which would enhance the efficiency of water use and contribute to water conservation in dry regions.


2019 ◽  
Vol 11 (12) ◽  
pp. 3460 ◽  
Author(s):  
Abdulaziz G. Alghamdi ◽  
Hesham M. Ibrahim

Applications of large amounts of biosolid to agricultural lands have raised the concern over its potential impact on co-transport of metal contaminants. In this study, bulk biosolid was fractioned into six macro- and nano-biosolid fraction sizes. We investigated variations in the physicochemical properties of the different biosolid fraction sizes, and assessed sorption affinity and transport of Pb in a loamy sand soil. Decreasing biosolid fraction size from macro to nano resulted in consistent increases in surface area, surface charge, and a decrease in pore size. Biosolid particles >1000 µm showed similar surface properties that differ from biosolid particles < 1000 µm. Sorption affinity for Pb was larger on nano-biosolid as compared to all macro-biosolid fraction sizes. This is mainly attributed to the larger surface area and zeta potential of nano-biosolid, leading to increased surface reactivity and greater stability. Total amount eluted of Pb was increased in the presence of macro- and nano-biosolid by 21.3% and 45.6%, respectively. Our findings suggest that the application of the >1000 µm biosolid fractions can help to minimize adverse effects of biosolid applied in areas susceptible to potential environmental risk of contamination by heavy metals. Further assessment of potential mobility of nano-biosolid at the field scale is needed before the recommendation of including such approach during land application of biosolid.


1986 ◽  
Vol 29 (2) ◽  
pp. 0389-0392 ◽  
Author(s):  
Jonathan Chaplin ◽  
Mike Lueders ◽  
David Rugg

2018 ◽  
Vol 10 (9) ◽  
pp. 6 ◽  
Author(s):  
Andre A. Diatta ◽  
Wade E. Thomason ◽  
Ozzie Abaye ◽  
Larry J. Vaughan ◽  
Thomas L. Thompson ◽  
...  

Mungbean [Vigna radiata (L.) Wilczek] is a short-duration and relatively drought-tolerant crop grown predominantly in the tropics. This grain legume can improve soil fertility through biological nitrogen (N) fixation. To assess the effects of Bradyrhizobium (group I) inoculation on yield and yield attributes of mungbean, a greenhouse study was conducted during Fall 2016 with two mungbean cultivars (‘Berken’ and ‘OK2000’), two inoculum treatments (inoculated and uninoculated), and two soil textures (loamy sand and silt loam). Pots were laid out in a completely randomized design and treatment combinations were replicated seven times. The main effects of cultivar and soil texture significantly (P ≤ 0.05) affected mungbean seed weight and plant residue mass. Seed yield (13%), plant residue (22%), and protein content (6%) of OK2000 were significantly higher than Berken cultivar. A 31% seed yield and 40% plant residue increase were recorded on silt loam soil compared to loamy sand soil. Significant increase in plant height (18%) and number of pods per plant (21%) were also recorded when mungbean plants were grown on silt loam compared to loamy sand soil. Bradyrhizobium inoculation significantly increased the number of pods per plant, the number of seeds per plant, and seed yield. [Cultivar × inoculation] and [cultivar × soil texture] interactions had significant (P ≤ 0.05) effects on number of seeds per pods and plant height, respectively. Understanding the agronomic practices and soil physical properties that may limit mungbean production could help in optimizing its establishment and growth in non-traditional growing areas.


1990 ◽  
Vol 4 (4) ◽  
pp. 754-758 ◽  
Author(s):  
W. Carroll Johnson ◽  
Benjamin G. Mullinix

Studies on the efficacy and economic analysis of Texas panicum management systems in corn were conducted in Georgia on a loamy sand soil in 1987, 1988, and 1989. Management systems that included butylate, EPTC, atrazine plus tridiphane, atrazine plus pendimethalin, atrazine plus trifluralin, paraquat, or ametryn acceptably control Texas panicum. Corn yields were not affected significantly by the Texas panicum management systems. Overall net returns calculated for corn production indicated that systems which included postemergence applications of atrazine, pendimethalin, trifluralin, paraquat, ametryn, or cultivation alone gave the highest net returns. Systems which included butylate, EPTC, or tridiphane frequently had significantly lower net returns.


2019 ◽  
Vol 141 ◽  
pp. 10-17 ◽  
Author(s):  
Richard Murphey Coy ◽  
David W. Held ◽  
Joseph W. Kloepper

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