Herbicide Performance in Rice (Oryza sativa) under Three Flooding Conditions

Weed Science ◽  
1984 ◽  
Vol 32 (2) ◽  
pp. 157-162 ◽  
Author(s):  
Edward P. Richard ◽  
Joe E. Street
Keyword(s):  
Oryza Sativa ◽  
Drought Stress ◽  
Weed Control ◽  
Weed Competition ◽  
Yield Losses ◽  
Early Season ◽  
Rice Yields ◽  
Weed Emergence ◽  
Principal Advantage

A 3-yr study was conducted to compare the performance of several herbicides applied alone and in mixtures under three flooding conditions in dry-seeded rice (Oryza sativaL. ‘Labelle’). When the soil remained moist during the 2-week unflooded periods (1979 and 1981), weed emergence was slowed and no advantage with respect to enhanced weed control and increased rice yields could be demonstrated over that of the standard sequential propanil (3′,4′-dichloropropionanilide) application. However, in 1980 when drought stress may have reduced initial postemergence activity and weeds emerged during the 14-day unflooded periods, differences in weed control between herbicides were obtained. Results of this study also indicate that yield losses from weed competition resulted primarily from early season competition, and that the principal advantage of the residual herbicides in dry-seeded rice may be to eliminate the need for retreatment with propanil when flooding is delayed or fields are drained.

Effects of Simulated MSMA Drift on Rice (Oryza sativa) Growth and Yield

Weed Science ◽  
1981 ◽  
Vol 29 (3) ◽  
pp. 303-308 ◽  
Author(s):  
E. P. Richard ◽  
H. R. Hurst ◽  
R. D. Wauchope
Keyword(s):  
Oryza Sativa ◽  
Gossypium Hirsutum ◽  
Plant Height ◽  
Weed Control ◽  
Developmental Stages ◽  
Growth And Yield ◽  
Stages Of Development ◽  
Early Season ◽  
Application Timing ◽  
Over The Top

Levels of MSMA (monosodium methanearsonate) that simulated drift (0.2, 0.39, and 0.78 kg/ha) were applied over-the-top to rice (Oryza sativaL. ‘Vista’, ‘Starbonnet’, or ‘Labelle’) after flooding at four developmental stages between early tillering and late jointing. The MSMA rates used were equivalent to, or lower than, the 0.78-kg/ha rate that would be applied as an over-the-top application to cotton (Gossypium hirsutumL.) for early season weed control. Over-the-top applications of MSMA did not affect heading and maturity dates of filled grains regardless of the rate or application timing. Reductions occurred, however, in plant height, number of panicles, and yield. In addition, the percentage of erect panicles showing typical “straighthead” symptoms increased. Rice sensitivity to MSMA depended on MSMA rate and stage of growth with injury being most severe as rice approached the reproductive stages of development. Because aerial applications of MSMA to cotton are normally made before rice reaches the reproductive stage, injury resulting from MSMA drift should be minimal.

Weed Competition in Rice

Weed Science ◽  
1968 ◽  
Vol 16 (2) ◽  
pp. 252-255 ◽  
Author(s):  
Roy J. Smith
Keyword(s):  
Oryza Sativa ◽  
Weed Competition ◽  
Early Season ◽  
Echinochloa Crusgalli ◽  
Late Season ◽  
Sesbania Exaltata ◽  
Hemp Sesbania

Barnyardgrass [Echinochloa crusgalli (L.) Beauv.], duck-salad [Heteranthera limosa (Sw.) Willd.], hemp sesbania [Sesbania exaltata (Raf.) Cory], and northern jointvetch [Aeschynomene virginica (L.) B.S.P.] significantly reduced rice [Oryza sativa L.] yields. Damage to rice increased as populations of barnyardgrass, hemp sesbania, and northern jointvetch increased. Barnyardgrass and duck-salad lowered yields during early season, but hemp sesbania and northern jointvetch decreased yields in late season.

Imazethapyr is Safe and Effective for Imidazolinone-Tolerant Rice Grown on Coarse-Textured Soils

2004 ◽  
Vol 18 (4) ◽  
pp. 1096-1100 ◽  
Author(s):  
Brian V. Ottis ◽  
John H. O'Barr ◽  
Garry N. McCauley ◽  
James M. Chandler
Keyword(s):  
Sand Content ◽  
Yield Losses ◽  
Red Rice ◽  
Surface Irrigation ◽  
Crop Response ◽  
Early Season ◽  
Rice Yields

A study was conducted in 2001 and 2002 in Texas to evaluate red rice control and crop response of imidazolinone-tolerant rice with imazethapyr on coarse-textured soils. Because imazethapyr was not registered for use on imidazolinone-tolerant rice on coarse-textured soils in Texas, crop response was evaluated to determine whether imidazolinone-tolerant rice yields would be reduced with sequential applications of imazethapyr on soils having greater than 50% sand content. The treatment factors consisted of preemergence (PRE) applications of imazethapyr at 50, 70, or 87 g ai/ ha followed by (fb) preflood (PREFLD) applications of 35 or 50 g/ha. Imazethapyr at 70 g/ha PRE fb 70 g/ha PREFLD was added as a seventh treatment. PRE applications were activated by rainfall or surface irrigation after application, and PREFLD applications were sprayed 1 to 2 d before application of the permanent flood. In both years, 100% red rice control was achieved with all rate combinations. Early-season visual rice injury ranged from 5 to 21% and did not result in yield losses, indicating that imazethapyr is safe on coarse-textured soils.

Maize/Weed Competition Experiments: Implications for Tropical Small-Farm Weed Control Research

1983 ◽  
Vol 19 (4) ◽  
pp. 341-347 ◽  
Author(s):  
R. Vernon ◽  
J. M. H. Parker
Keyword(s):  
Weed Control ◽  
Critical Period ◽  
Maize Yield ◽  
Weed Competition ◽  
Labour Demand ◽  
Small Farms ◽  
Yield Losses ◽  
Small Farm ◽  
Control Research ◽  
Maize Yields

SUMMARYTwo sets of experiments examined the effects of weeds on maize yields using weeding methods typical of small farms in Zambia where oxen are used for cultivation. Maize yield losses of 30% due to weeds were evident with common weeding practices. A critical period of competition, during which the crop should be kept clean, was demonstrated from 10 to 30 days after emergence. This is a period of peak labour demand and the prospect of using chemical weed control to ease the situation is considered. The value of weed competition data, given its variability between sites, is discussed.

Evaluation of Herbicides for Weed Control in Chicory (Cichorium intybus)

2004 ◽  
Vol 18 (3) ◽  
pp. 540-544 ◽  
Author(s):  
Robert G. Wilson ◽  
John A. Smith ◽  
C. Dean Yonts
Keyword(s):  
Weed Control ◽  
Field Trials ◽  
Cichorium Intybus ◽  
Weed Competition ◽  
Root Yield ◽  
Early Season ◽  
Chicory Root

Field trials were conducted in 1995 through 2002 to expand the development of chicory by determining the potential for tank mixtures of benefin, trifluralin, or pronamide applied preplant incorporated (PPI) and triflusulfuron methyl or imazamox postemergence (POST) for selective weed control in chicory. Lack of early-season weed control resulted in an 88% reduction in chicory root yield in 1995 to 1996 and an 85% reduction in 2001 to 2002 and demonstrated the susceptibility of chicory plants to early-season weed competition. In the first experiment, pronamide at 1.1 kg ai/ha PPI plus benefin at 1.3 kg ai/ha or trifluralin at 0.56 kg/ha were selective for chicory and controlled weed populations 90% on average with root yields that were 89% of the hand-weeded treatment. Triflusulfuron methyl POST at 17 g/ha caused early-season chicory injury. In the second experiment, trifluralin PPI at 0.56 kg/ha followed by imazamox POST at 36 g/ha controlled weeds 95% on average with a chicory root yield of 74 t/ha, which was 109% of the yield of the hand-weeded treatment.

Early-Season Weed Control Using Herbicides with Adjuvants in Direct-Seeded Onion

2013 ◽  
Vol 27 (2) ◽  
pp. 369-372 ◽  
Author(s):  
James R. Loken ◽  
Harlene M. Hatterman-Valenti
Keyword(s):  
Weed Control ◽  
Seed Oil ◽  
Field Trials ◽  
Yield Losses ◽  
Fresh Weight ◽  
Early Season ◽  
Common Lambsquarters ◽  
Redroot Pigweed ◽  
Direct Seeded ◽  
Petroleum Oil

Early-season weed competition may cause substantial yield losses in onion. Oxyfluorfen and bromoxynil are POST herbicide options for weed control once onion has developed two leaves, which often takes 4 to 6 wk. Multiple applications of oxyfluorfen at 35 and 18 g ai ha−1and bromoxynil at 35 and 18 g ae ha−1with adjuvants were evaluated for onion safety and weed control under controlled greenhouse conditions. Oxyfluorfen at 35 g ha−1plus organosilicone surfactant caused 42% onion injury at 12 d after three sequential applications. Onion treated with bromoxynil at 18 g ha−1plus high surfactant oil concentrate had lower fresh weight (0.7 g) compared to methylated seed oil (MSO) (1.2 g) or petroleum oil concentrate (POC) (1.3 g) at the same bromoxynil rate. The addition of nonionic surfactant to bromoxynil, averaged across bromoxynil rates, provided 17 and 39% control of redroot pigweed and common lambsquarters, respectively. Redroot pigweed control with oxyfluorfen at 35 or 18 g ha−1plus any tested adjuvant was excellent (≥ 93%). Results suggested the use of POC or MSO with either oxyfluorfen or bromoxynil for subsequent field trials because of similar common lambsquarters and redroot pigweed control and onion safety.

Multiple Applications of Reduced-Rate Herbicides for Weed Control in Onion

2010 ◽  
Vol 24 (2) ◽  
pp. 153-159 ◽  
Author(s):  
James R. Loken ◽  
Harlene M. Hatterman-Valenti
Keyword(s):  
Weed Control ◽  
Field Experiments ◽  
Total Yield ◽  
Weed Competition ◽  
Early Season ◽  
Common Lambsquarters ◽  
Redroot Pigweed ◽  
Application Rates ◽  
Herbicide Treatments ◽  
Reduced Rate

Field experiments were conducted at Oakes, Absaraka, and Tappen, ND, in 2006 and repeated at Oakes and Absaraka, ND, in 2007 to evaluate early season weed control of common lambsquarters and redroot pigweed in onion with POST herbicides applied at multiple reduced rates (microrates) and to determine whether microrate herbicide treatments effectively reduced early season broadleaf weed competition, caused crop injury, or affected yield. Application rates of bromoxynil, oxyfluorfen, metribuzin, and acifluorfen were reduced to 0.25, 0.13, and 0.06× of their lowest labeled rate and applied in sequential applications (every 7 d) either two or three times. The 0.25× rate of bromoxynil (70.1 g ae/ha) provided the greatest control of common lambsquarters (95%). The 0.25× rates of bromoxynil and oxyfluorfen (70.1 g ai/ha) provided the greatest control of redroot pigweed (93 and 85%, respectively). Microrate applications of metribuzin or acifluorfen did not effectively control common lambsquarters or redroot pigweed. In 2006, no onion injury was observed. However, in 2007, applications of oxyfluorfen resulted in approximately 15% injury, regardless of the herbicide rate or the number of applications. Plants outgrew symptoms by 4 wk after treatment and were similar to the untreated plants. Onion treated with oxyfluorfen had the greatest total yield, followed by onion treated with bromoxynil. Onion treated with acifluorfen had a greater total marketable bulb yield than onion treated with metribuzin, but yield was considered poor compared to the other herbicide treatments. Three microrate applications provided greater weed control and increased yield compared with two applications across herbicides and rates. Results suggest that microrate applications of bromoxynil and oxyfluorfen will provide early season broadleaf weed control in onion.

CRITICAL PERIOD OF WEED INTERFERENCE IN FIELD-SEEDED TOMATOES AND ITS RELATION TO WATER STRESS AND SHADING

1987 ◽  
Vol 67 (2) ◽  
pp. 575-583 ◽  
Author(s):  
S. E. WEAVER ◽  
C. S. TAN
Keyword(s):  
Water Stress ◽  
Lycopersicon Esculentum ◽  
Weed Control ◽  
Critical Period ◽  
Weed Competition ◽  
Yield Losses ◽  
Weed Interference ◽  
Light Levels

The critical period of weed interference in field-seeded tomatoes (Lycopersicon esculentum L. ’TH 318’) was determined in 1981, 1982 and 1983. The minimum weed-free period varied among years from 7 to 9 wk after sowing, while the maximum weed-infested period varied from 5 to 6 wk after sowing. A minimum of two weed control operations during the critical period was required to prevent yield losses. Reductions in tomato yields were correlated with weed dry weights and could be attributed both to reductions in light levels due to shading and weed competition for water which resulted in stomatal closure.Key words: Competition, critical period, weed, tomato, Lycopersicon esculentum L.

Weed Control in Rice (Oryza sativa) with Quinclorac and Bensulfuron Coating of Granular Herbicides and Fertilizer

1995 ◽  
Vol 9 (3) ◽  
pp. 494-498 ◽  
Author(s):  
Michael P. Braverman
Keyword(s):  
Oryza Sativa ◽  
Weed Control ◽  
Rice Yields

Weed control with thiobencarb, molinate, or fertilizer granules coated with quinclorac or bensulfuron was evaluated in 1992 and 1993. With thiobencarb or fertilizer granules, less than 55% control of 4-leaf junglerice was obtained, regardless of additional herbicide coating. Coating thiobencarb or fertilizer granules with quinclorac at 550 g ai/ha increased junglerice control, but was not satisfactory. Molinate granules at 4.4 kg ai/ha controlled junglerice at least 81% and improved rice yields over fertilizer or thiobencarb granules. Fertilizer coated with bensulfuron at 111 g ai/ha controlled ducksalad 86 to 96%.

Competitiveness with Weeds of Soybean Cultivars with Different Maturity and Canopy Width Characteristics

2007 ◽  
Vol 21 (4) ◽  
pp. 1082-1088 ◽  
Author(s):  
Dawn E. Nordby ◽  
Dustin L. Alderks ◽  
Emerson D. Nafziger
Keyword(s):  
Weed Control ◽  
Weed Management ◽  
Growth Stage ◽  
Competitive Ability ◽  
Field Studies ◽  
Yield Potential ◽  
Weed Competition ◽  
Early Season ◽  
Soybean Cultivars ◽  
Maturity Date

Field studies were conducted in 2005 at five locations throughout Illinois to determine the effect of maturity date and canopy width characteristics of selected glyphosate-resistant soybean cultivars on competitive ability against weeds. Natural weed populations at all sites were allowed to compete with the soybean cultivars until the V1, V3, V5, or V7 growth stage and then removed with an application of glyphosate. Light-interception readings, weed control ratings, and soybean yield were all measured to compare cultivars. Cultivars of later maturities tended to withstand early season weed competition better and attained higher yields when weeds were removed at later timings than those of earlier maturity. Although canopy width differed moderately among cultivars in some cases, canopy width had no effect on the ability of soybeans to compete with weeds. Thus, choosing soybean cultivars of later maturity might provide more flexibility in weed management and might reduce losses due to weeds, but that benefit needs to be balanced with yield potential.

Sign in / Sign up

Export Citation Format

Share Document