Rice yield and quality as affected by cultivar and red rice (Oryza sativa) density

Weed Science ◽  
2005 ◽  
Vol 53 (4) ◽  
pp. 499-504 ◽  
Author(s):  
Brian V. Ottis ◽  
Kenneth L. Smith ◽  
Robert C. Scott ◽  
Ronald E. Talbert
Keyword(s):  
Rice Yield ◽  
Field Studies ◽  
Rice Cultivars ◽  
University Of Arkansas ◽  
Red Rice ◽  
Cultivated Rice ◽  
Yield And Quality ◽  
The University ◽  
Extension Center

Previous research has examined the extent to which red rice affects both yield and grain quality of cultivated rice. However, this research was conducted over 15 yr ago. Modern long-grain rice cultivars have the potential to produce yields above 10,000 kg ha−1; however, it is unknown whether modern rice cultivars sacrifice competitiveness to achieve higher yields, or if, in fact, they are more competitive. Field studies were conducted in 2002 and 2003 at the Southeast Research and Extension Center near Rohwer, AR, and at the University of Arkansas Pine Bluff Research Farm near Lonoke, AR, to investigate the effect of red rice density on interference between red rice and five rice cultivars (‘CL161’, ‘Cocodrie’, ‘LaGrue’, ‘Lemont’, and ‘XL8’). White rice yield reductions were between 100 and 755 kg ha−1for every red rice plant m−2. The hybrid rice, XL8, had higher yields than the conventional cultivars. Red rice contamination in milling samples increased linearly as a function of red rice density at Lonoke and Rohwer in 2003. Dockage for each cultivar was calculated on the basis of the relationship between red rice density and red rice contamination. Semidwarf Lemont was the most contaminated and hybrid XL8 the least contaminated by the various densities of red rice.

Red Rice (Oryza sativa) Emergence Characteristics and Influence on Rice Yield At Different Planting Dates

Weed Science ◽  
2009 ◽  
Vol 57 (1) ◽  
pp. 94-102 ◽  
Author(s):  
Vinod K. Shivrain ◽  
Nilda R. Burgos ◽  
David R. Gealy ◽  
Kenneth L. Smith ◽  
Robert C. Scott ◽  
...  
Keyword(s):  
Rice Yield ◽  
Rice Cultivar ◽  
Planting Date ◽  
Rice Cultivars ◽  
Yield Losses ◽  
Red Rice ◽  
Cultivated Rice ◽  
Planting Dates ◽  
Planting Time ◽  
Extension Center

Cultivated rice yield losses due to red rice infestation vary by cultivar, red rice density, and duration of interference. The competition effects of red rice could be influenced further by emergence characteristics, red rice biotype, and planting time of cultivated rice. We aimed to characterize the emergence of red rice biotypes at different planting dates and evaluate the effect of red rice biotype, rice cultivar, and planting date on cultivated rice yield loss. Field experiments were conducted at the Southeast Research and Extension Center, Rohwer, AR, and at the Arkansas Rice Research and Extension Center, Stuttgart, AR, in the summer of 2005 and 2006. The experimental design was a split-split plot with three or four replications. Planting time, ClearfieldTM(CL) rice cultivar, and red rice biotype were the main plot, subplot, and sub-subplot factors, respectively. There were three planting times from mid-April to mid-May at 2-wk intervals. CL rice cultivars, CL161 and hybrid CLXL8, and 12 red rice biotypes were planted. The emergence rate and coefficient of uniformity of germination differed among some red rice biotypes within a planting time. Planting date affected the emergence characteristics of red rice biotypes. The mean emergence rate of red rice was 0.043 d−1in the mid-April planting and 0.058 d−1in the late April planting. For the mid-April planting, 50% of red rice biotypes emerged in 20 ± 2 d compared with 15 ± 2 d for CL rice cultivars. Yield losses due to red rice biotypes generally increased in later planting dates, up to 49%. Yield losses due to interference from red rice biotypes ranged from 14 to 45% and 6 to 35% in CL161 and CLXL8, respectively. Cultivated rice became less competitive with red rice in later plantings, resulting in higher yield losses.

scholarly journals Initial development of red and cultivated rice in response to light and air temperature

2013 ◽  
Vol 35 (4) ◽  
pp. 510-518 ◽  
Author(s):  
Eduardo Venske ◽  
Carlos Eduardo Schaedler ◽  
Mariana Peil da Rosa ◽  
Carolina Terra Borges ◽  
Luis Antonio de Avila ◽  
...  
Keyword(s):  
Air Temperature ◽  
Root Length ◽  
Dry Weight ◽  
Rice Cultivars ◽  
Red Rice ◽  
Cultivated Rice ◽  
Initial Development ◽  
Response To Temperature ◽  
The Relationship

Light is an important factor in the cold protection process in plants. The objective of this study was to evaluate the relationship between temperatures and levels of quantity and quality of light on the initial development of rice cultivars and red rice biotypes. Two experiments were conducted, in the laboratory and in the greenhouse, from July to November 2012. The factors studied in experiment I were: temperatures (25 ºC and 18/13 ºC); cultivars/biotypes (IRGA 424 and PUITÁ INTA-CL/AV 6716 and AV 6722) and light (white, blue, green, yellow and red, 86% and 93% shading and dark). In the second experiment, the factors were seasons (August and November); cultivars/biotypes (IRGA 424 and PUITÁ INTA-CL/AV 6716 and AV 6722) and light (white with cover, white, blue, green, yellow and red, 86% and 93% shading). Were evaluated normal seedlings, shoot and root length, shoot and root dry weight and leaf area. The cultivars and biotypes studied have a similar behavior in response to temperature and light during early development. Light, especially the red wavelength, has increased cold tolerance in rice.

Broadleaf Weed Control and Potato Crop Safety with Postemergence Rimsulfuron, Metribuzin, and Adjuvant Combinations

2004 ◽  
Vol 18 (3) ◽  
pp. 750-756 ◽  
Author(s):  
Pamela J. S. Hutchinson ◽  
Charlotte V. Eberlein ◽  
Dennis J. Tonks
Keyword(s):  
Weed Control ◽  
Seed Oil ◽  
Tuber Yield ◽  
Potato Crop ◽  
Field Studies ◽  
Common Lambsquarters ◽  
Yield And Quality ◽  
The University ◽  
Extension Center ◽  
University Of Idaho

The effects of postemergence rimsulfuron, metribuzin, and adjuvant combinations on potato crop safety and weed control were evaluated in field studies conducted at the University of Idaho Aberdeen Research and Extension Center in 1999 and 2000. Rimsulfuron at 26 g ai/ha plus metribuzin at 0, 140, or 280 g ai/ha was combined with nonionic surfactant (NIS), crop oil concentrate (COC), or methylated seed oil (MSO) in a 3 by 3 factorial with two controls. Under cool, cloudy conditions in 1999, initial ‘Russet Burbank’ potato injury was greater when metribuzin was included in the tank mixture than when rimsulfuron was applied alone, regardless of adjuvant. Under warmer conditions in 2000, however, adding MSO or COC to the tank mixture caused more injury than adding NIS. Rimsulfuron did not provide acceptable season-long common lambsquarters control in 1999 (76%) or in 2000 (88%), regardless of adjuvant. Rimsulfuron combined with metribuzin at 140 or 280 g/ha provided ≥95% common lambsquarters control both years, regardless of adjuvant. Among adjuvants, using MSO (1999 and 2000) or COC (2000) in the spray mixture improved common lambsquarters control compared with using NIS. Tuber yield and quality were not reduced as a result of metribuzin rate or adjuvant treatments either year compared with the weed-free control.

Red Rice (Oryza sativa) Biology. I. Characterization of Red Rice Ecotypes

1999 ◽  
Vol 13 (1) ◽  
pp. 12-18 ◽  
Author(s):  
José A. Noldin ◽  
James M. Chandler ◽  
Garry N. McCauley
Keyword(s):  
Flag Leaf ◽  
Natural Hybridization ◽  
Rice Cultivars ◽  
Red Rice ◽  
Cultivated Rice ◽  
Seed Shattering ◽  
Seed Moisture ◽  
Biology I ◽  
Plant Characteristics

Plant characteristics of red rice ecotypes obtained from Arkansas, Louisiana, Mississippi, and Texas, including 11 strawhulled, five blackhulled, two goldhulled, and one brownhulled type, were evaluated under field conditions. Most ecotypes were uniform and stable but manifested considerable genetic variability. Red rice plants had pubescent leaves, were taller with lighter green color, and produced more tillers and panicles per plant than rice cultivars ‘Lemont,’ ‘Mars,’ and ‘Maybelle.’ Most ecotypes were highly susceptible to seed shattering starting about 14 d after anthesis when seed moisture was more than 25%. Seeds of most ecotypes were highly dormant at harvest. Rice cultivars had a larger flag leaf and more total leaf area per plant at anthesis and produced more seeds per panicle than red rice. Some red rice ecotypes had plant characteristics closely related to cultivated rice suggesting natural hybridization with rice.

Differential Tolerance of Clearfield Rice Cultivars to Imazamox

2011 ◽  
Vol 25 (2) ◽  
pp. 192-197 ◽  
Author(s):  
Jason A. Bond ◽  
Timothy W. Walker
Keyword(s):  
Growth Stage ◽  
Rice Yield ◽  
Field Studies ◽  
First Year ◽  
Growth Stages ◽  
Rice Cultivars ◽  
Rough Rice ◽  
Rice Yields ◽  
Clearfield Rice ◽  
Two Hybrid

Field studies were conducted to compare the response of one inbred (‘CL161’) and two hybrid (‘CLXL729’ and ‘CLXL745’) Clearfield (CL) rice cultivars to imazamox. Imazamox was applied at 44 and 88 g ai ha−1to rice in the panicle initiation (PI) and PI plus 14 d (PI + 14) growth stages and at 44 g ha−1to rice in the midboot growth stage. Maturity of hybrid CL cultivars was delayed following imazamox at 44 g ha−1applied at PI + 14 and midboot. Furthermore, imazamox at 44 g ha−1, applied at midboot, delayed maturity of CLXL745 more than CLXL729. Expressed as a percentage of the weed-free control plots, rough rice yields for CLXL729 were 91% following imazamox at 44 g ha−1applied at PI + 14, 78% following imazamox at 44 g ha−1applied at midboot, and 77% for imazamox at 88 g ha−1applied at PI + 14. Rough rice yield for CLXL745 was 77 to 92% of the control following all imazamox treatments. All imazamox treatments reduced CLXL745 rough rice yield compared with CL161. Rough rice yield, pooled across CL cultivar, varied with imazamox treatment between years, and these differences may have been a consequence of lower temperatures and solar radiation in the first year. Hybrid CL cultivars CLXL729 and CLXL745 were less tolerant than was CL161 when imazamox was applied at nonlabeled rates (88 g ha−1) and/or timings (PI + 14 or midboot). Because of variability in rice growth stages and irregularities in imazamox application in commercial fields, inbred CL cultivars should be planted where an imazamox application will likely be required.

Pendimethalin Applications in Stale Seedbed Rice Production

2009 ◽  
Vol 23 (1) ◽  
pp. 167-170 ◽  
Author(s):  
Jason A. Bond ◽  
Timothy W. Walker ◽  
Clifford H. Koger
Keyword(s):  
Production System ◽  
Rice Yield ◽  
Field Studies ◽  
Rice Production ◽  
Seedling Vigor ◽  
Rice Cultivars ◽  
Seedling Density ◽  
Application Timing ◽  
Emulsifiable Concentrate ◽  
Capsule Suspension

Field studies were conducted from 2005 through 2007 to determine the response of three rice cultivars (‘Cocodrie’, ‘Wells’, and ‘Lemont’) to three application timings and two formulations of pendimethalin in a stale seedbed rice production system. Pendimethalin formulated as an emulsifiable concentrate and capsule suspension was applied to rice 0, 3, and 7 d after planting. No visual injury was detected for any cultivar. Seedling density, days to 50% heading, and rice yield were not affected by pendimethalin formulation or application timing. The practice of planting cultivars with excellent seedling vigor into nondisturbed soils with greater available moisture could provide an opportunity to use pendimethalin as a preemergence herbicide for rice production.

scholarly journals Thrips Control in Cotton with In-Furrow Insecticides in Northeast Arkansas, 1994

1995 ◽  
Vol 20 (1) ◽  
pp. 218-218
Author(s):  
Glenn Studebaker
Keyword(s):  
University Of Arkansas ◽  
Severe Damage ◽  
The University ◽  
Extension Center

Abstract ‘Plots of DES 119’ cotton were planted on 20 May at the University of Arkansas Northeast Research and Extension Center. Granular compounds were applied by Gandy box on the planter. In-furrow liquids were applied with a CO2 powered system mounted on the planter directing sprays into the furrow. The sprayer was calibrated to deliver 5.5 gal/acre at 42 psi through 8002 flat fan nozzles. Plots were four 38-inch rows, 50-ft long, arranged in a RCBD with 4 replications. Damage ratings were made based on a scale of 1-10 with 10 = severe damage. Thrips counts were made by collecting 5 plants from each plot and washing the plants through a series of sieves, counting the thrips collected in the final sieve. Yields were taken by harvesting the center two rows of each plot.

scholarly journals The effects of PLA biodegradable and polypropylene nonwoven crop mulches on selected components of tomato grown in the field

2014 ◽  
Vol 26 (2) ◽  
pp. 163-167 ◽  
Author(s):  
Izabela Zawiska ◽  
Piotr Siwek
Keyword(s):  
Ascorbic Acid ◽  
Dry Matter ◽  
Soluble Sugar ◽  
Soluble Sugars ◽  
Growing Season ◽  
Field Studies ◽  
Nitrate Content ◽  
Yield And Quality ◽  
Cotyledon Stage

ABSTRACT The results of two years (2010-2011) of field studies using two types of nonwoven mulches (one biodegradable, polylactic acid PLA 54 g m-2, and traditional polypropylene PP 50 g m-2) on the yield and quality of tomato are presented. Seeds of tomato (‘Mundi’ F1) were sown in a greenhouse, in containers filled with perlite and sand, and then the plants at the cotyledon stage were replanted in multipot trays filled with substrate for vegetable plants. In the last week of May, seedlings were planted on mulches in the field at a spacing of 50 × 100 cm. The mulch was maintained throughout the growing season. A plot that remained unmulched served as the control. Tomatoes were harvested once a week. The fruits were evaluated for L-ascorbic acid, dry matter, soluble sugars and nitrate content. In 2011, the analysis of the plant material showed that the concentration of L-ascorbic acid was about 23% higher in the tomato fruits harvested from plants grown on biodegradable PLA 61 g m-2 mulch in comparison to the control. A similar effect was demonstrated for the soluble sugar concentration in 2011 for both types of nonwovens.

Response of Rice (Oryza sativa) to Low Rates of Glyphosate and Glufosinate

2011 ◽  
Vol 25 (2) ◽  
pp. 198-203 ◽  
Author(s):  
Brad Davis ◽  
Robert C. Scott ◽  
Jason K. Norsworthy ◽  
Edward Gbur
Keyword(s):  
Yield Loss ◽  
Flag Leaf ◽  
Field Studies ◽  
Leaf Length ◽  
University Of Arkansas ◽  
Yield Losses ◽  
Time Of Application ◽  
Flag Leaf Length ◽  
The University ◽  
Significant Injury

Field studies were conducted in 2007 and 2008 at the University of Arkansas at Pine Bluff farm near Lonoke to evaluate and compare the effects of low rates of glufosinate and glyphosate on rice. Two rice cultivars were seeded, and glyphosate and glufosinate were applied at 1/2, 1/4, and 1/8 of the labeled use rate of 870 g ae ha−1and 616 g ai ha−1, respectively, at the three- to four-leaf, panicle initiation (PI), and boot stages. Rice canopy height reductions, reduction in flag leaf length, prolonged maturity, and yield losses were caused by both herbicides at all evaluated application timings. Although both herbicides caused significant injury, symptoms varied greatly between the two herbicides. Glufosinate injury to rice was more rapid and visually intense than with glyphosate. Glufosinate symptoms, which consisted of rapid necrosis, were visible in 1 to 2 d, whereas glyphosate symptoms, stunting and chlorosis, became visible after 7 to 10 d or not at all depending on time of application. Glyphosate applied at the 1/2× rate to rice in the boot growth stage caused less than 10% injury at 3 wk after treatment but resulted in 80% yield loss. Glufosinate at boot caused 80% injury and 80% yield loss. Glyphosate symptoms from PI and boot timings were typically only visible at heading and included malformed panicles and shortened flag leaves. Harvested grain seed weights were reduced as much as 14% by either herbicide applied at PI and boot. Germination of harvested grain was not affected by any treatment. At the rates evaluated in this research, glufosinate-induced injury to rice can be just as detrimental as glyphosate in reducing yield.

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