Gene flow from single and stacked herbicide-resistant rice (Oryza sativa): modeling occurrence of multiple herbicide-resistant weedy rice

Abstract Weedy rice (Oryza sativa f. spontanea or O. sativa complex) has become a severe threat to Malaysian rice (Oryza sativa L.) granaries after the direct-seeding method of rice cultivation was introduced in the late 1980s. Since then, researchers have studied the biology and ecology of weedy rice, and espoused the evolutionary theory of the origin of Malaysian weedy rice. This review paper aimed to synthesize the body of knowledge about weedy rice and the evolution of herbicide-resistant weedy rice in Malaysia. The imidazolinone (IMI) herbicide component of the Clearfield® Production System (CPS) rice package has become among the most effective tools for weedy rice control. However, the sole dependence on this technology and farmers’ ignorance about the appropriate use of IMI herbicides with the CPS rice package have resulted in the evolution of IMI-resistant (IMI-R) weedy rice. This has reduced the efficacy of IMI herbicides on weedy rice, ultimately nullifying the benefit of CPS rice in affected fields. At present, it is assumed that IMI-R weedy rice populations are widely distributed across the rice granaries in Malaysia. Therefore, it is important that integrated management measures be adopted comprehensively by Malaysian rice growers to curb the spread of IMI-R weedy rice problem in Malaysia, especially in the fields planted with CPS rice. This review focuses on the biology of Malaysian weedy rice, history of establishment of weedy rice in Malaysian rice fields, impact of herbicide-resistant rice technology on the evolution of IMI-R weedy rice in Malaysia, the distribution of resistant weedy rice populations across Peninsular Malaysian rice granaries, the weedy rice resistance mechanisms, and weedy rice management. The synthesis of all this information is helpful to researchers, policy makers, the private agricultural industry, advisors to farmers, and proactive farmers themselves with the goal of working toward sustainable rice production.

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Gene flow from herbicide resistant genetically modified rice to conventional rice (Oryza sativa L.) cultivars

Journal of Ecology and Environment ◽

10.5141/ecoenv.2015.042 ◽

2015 ◽

Vol 38 (4) ◽

pp. 397-403 ◽

Cited By ~ 5

Author(s):

Sung Min Han ◽

Bumkyu Lee ◽

Ok Jae Won ◽

Ki Seon Hwang ◽

Su Jeoung Suh ◽

...

Keyword(s):

Oryza Sativa ◽

Gene Flow ◽

Oryza Sativa L ◽

Genetically Modified ◽

Genetically Modified Rice ◽

Herbicide Resistant

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Gene Flow from Transgenic PPO-inhibiting Herbicide-resistant Rice to Weedy Rice, and Agronomic Performance by Their Hybrids

Journal of Plant Biology ◽

10.1007/s12374-019-0013-6 ◽

2019 ◽

Vol 62 (4) ◽

pp. 286-296 ◽

Cited By ~ 1

Author(s):

Kyong-Hee Nam ◽

Do Young Kim ◽

Ye Seul Moon ◽

In Soon Pack ◽

Soon-Chun Jeong ◽

...

Keyword(s):

Gene Flow ◽

Weedy Rice ◽

Agronomic Performance ◽

Herbicide Resistant

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Status of Weedy Rice (Oryza sativa L.) Infestation and Management Practices in Southern Brazil

Weed Science ◽

10.1017/wsc.2021.24 ◽

2021 ◽

pp. 1-35

Author(s):

Luis A. Avila ◽

José A. Noldin ◽

Carlos H. P. Mariot ◽

Paulo F.S. Massoni ◽

Marcus V. Fipke ◽

...

Keyword(s):

Oryza Sativa ◽

Management Practices ◽

Oryza Sativa L ◽

Conventional Tillage ◽

Weedy Rice ◽

Extension Agents ◽

Southern Brazil ◽

Herbicide Resistant ◽

Rice Area ◽

Infestation Status

Abstract Weedy rice (WR) (Oryza sativa L.) is the most troublesome weed infesting rice paddies in Brazil. Several changes have occurred in this region regarding crop management, especially WR control based on the Clearfield™ (CL) Rice Production System launched in 2003. This survey’s objective was to evaluate the WR infestation status by assessing the producers’ perception and the management practices used in southern Brazil after eighteen years of CL use in Brazil. Rice consultants and extension agents distributed a questionnaire with 213 producers in the Rio Grande do Sul (RS) and Santa Catarina (SC) state in the 2018/19 growing season. In RS, most farms are larger than 150 ha, farmers use minimal or conventional tillage, permanent flooding, adopted the CL system for more than two years, use clomazone PRE tank-mixed with glyphosate at the rice spiking stage, and use crop rotation with soybean [Glycine max (L.) Merr.] or pasture. In SC, rice farms are small, averaging from 20 to 30 ha, farmers predominantly plant pre-germinated rice and do not rotate rice with other crops and roguing is practiced. Comparing both states, the CL System is used in 99.5, and 69.3% of the total surveyed rice area in RS and SC, respectively. Imidazolinone-resistant WR is present in 68.4 and 26.6% of rice farms in RS and SC, respectively. Rice cultivation in Brazil is currently coexisting with WR with minimal integration of control methods. However, integrated practices can control this weed and are fundamental to the sustainability of systems based on herbicide-resistant rice cultivars.

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Mutations in the red rice ALS gene associated with resistance to imazethapyr

Weed Science ◽

10.1614/ws-04-111r1.1 ◽

2005 ◽

Vol 53 (5) ◽

pp. 567-577 ◽

Cited By ~ 42

Author(s):

Satyendra N. Rajguru ◽

Nilda R. Burgos ◽

Vinod K. Shivrain ◽

James McD. Stewart

Keyword(s):

Gene Flow ◽

Ssr Markers ◽

Point Mutations ◽

Acetolactate Synthase ◽

Weedy Rice ◽

Rice Cultivars ◽

Red Rice ◽

Coding Region ◽

Gene Sequences ◽

Herbicide Resistant

The introduction of Clearfield (CL) rice cultivars resistant to imidazolinone herbicides, acetolactate synthase (ALS) inhibitors, has raised concerns of gene flow to weedy rice genotypes collectively called “red rice” that infest rice-growing areas in the southern United States. This experiment was conducted to study hybridization between CL rice and red rice using simple sequence repeats (SSR) markers, identify mutations in the ALS gene of imazethapyr-resistant red rice, and to detect the introgression of the ALS-resistant gene from CL rice into red rice. Natural outcrossing experiments between CL rice and strawhull (SH) red rice were set up in Stuttgart, AR, in 2002 and 2003. Putative red rice hybrids were detected among volunteer plants in the following year. Hybridization was confirmed using SSR markers, and introgression of the resistant ALS gene from CL rice to red rice was detected by ALS gene sequencing. The ALS gene sequences of U.S. rice cultivars ‘Bengal’ and ‘Cypress’, SH red rice, CL rice (CL161), and imazethapyr-resistant red rice/CL rice hybrids were compared. Nucleotide sequences of the ALS gene from the rice cultivars were identical. Three point mutations were present in the SH red rice ALS gene coding region relative to Bengal/Cypress. One of these resulted in the substitution of Asp630for Glu630. The ALS gene sequences of confirmed hybrids were identical to that of the herbicide-resistant pollen source, CL161. We identified four ALS gene mutations in the herbicide-resistant red rice hybrids relative to the susceptible rice cultivars. One point mutation, resulting in a substitution of Ser653with Asn, was linked to ALS resistance in callus tissue derived from a Kinmaze rice line from Japan. The other three mutations (Ser186—Pro, Lys416—Glu, and Leu662—Pro) are novel. This experiment confirmed that gene flow from imidazolinone-resistant rice resulted in herbicide-resistant red rice plants.

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Sensitivity to salinity at the emergence and seedling stages of barnyardgrass (Echinochloa crus-galli), weedy rice (Oryza sativa), and rice with different tolerances to ALS-inhibiting herbicides

Weed Science ◽

10.1017/wsc.2020.72 ◽

2020 ◽

pp. 1-13

Author(s):

Silvia Fogliatto ◽

Lorenzo Patrucco ◽

Marco Milan ◽

Francesco Vidotto

Keyword(s):

Oryza Sativa ◽

Seedling Growth ◽

Salt Content ◽

Acetolactate Synthase ◽

The Other ◽

Carotenoid Content ◽

Weedy Rice ◽

Root Weight ◽

Rice Varieties ◽

Herbicide Resistant

Abstract Salinization is affecting many rice (Oryza sativa L.) areas worldwide and weed infestation, together with the occurrence of herbicide-resistant populations, is further limiting rice yield. This study aimed at evaluating the effect of water salinity on the emergence and seedling growth of five Italian barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.] populations (three sensitive and two resistant to acetolactate synthase–inhibiting herbicides), three Italian weedy rice (Oryza sativa L.) populations (all sensitive to imazamox), and two rice varieties (the conventional ‘Baldo’ variety and the imazamox-tolerant ‘CL80’ one). In 2017, seeds were sown in alveolar trays filled with sand, a nutrient solution, and water with the following salt concentrations: 0, 50, 100, 150, 200, and 250 mM NaCl. Plant emergence (after 15 d), plant height, shoot and root weight, chlorophyll a, chlorophyll b, and carotenoid content were measured at 40 d after sowing. Echinochloa crus-galli showed a higher tolerance to salinity than O. sativa and rice. All species were affected more at the seedling stage than at emergence. A variable behavior of the herbicide-resistant populations was shown; one resistant E. crus-galli population was affected more by salinity and showed a lower emergence rate (about 20% against 40% emergence of the other populations at the highest salt concentration) and reduced seedling growth, while the other resistant population’s response was similar to that of the sensitive populations. The chlorophyll content increased as the salt content increased in all E. crus-galli populations. The highest emergence and growth reduction in O. sativa were recorded in the imazamox-tolerant rice. Rice and O. sativa were able to grow only up to 50 mM. Echinochloa crus-galli populations are probably favored under saline conditions, while lower infestation by O. sativa can be expected.

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Weedy Rice Update in Arkansas, USA and Adjacent Locales

Weed Science ◽

10.1017/wsc.2021.45 ◽

2021 ◽

pp. 1-40

Author(s):

Nilda Roma-Burgos ◽

Thomas R. Butts ◽

Isabel S. Werle ◽

Sunny Bottoms ◽

Andy Mauromoustakos

Keyword(s):

Oryza Sativa ◽

Crop Rotation ◽

Control Strategies ◽

Weedy Rice ◽

Extension Agents ◽

County Extension Agents ◽

Herbicide Resistant ◽

Resistance Evolution ◽

Production Practices ◽

E Mail

Abstract Weedy rice (Oryza sativa L.) is among the most problematic weeds in rice (Oryza sativa L.) production. The commercialization of herbicide-resistant (HR) rice nearly two decades ago provided an effective tool to manage weedy rice; however, resistance evolution and volunteer HR hybrid rice kept weedy rice at the forefront of rice weed control needs. This research aimed to assess the prevalence and severity of weedy rice infestations, identify production practices that may have contributed to an increase in weedy rice, and identify control strategies that may still be effective on weedy rice across Arkansas and adjacent US mid-south locales. Two questionnaires, one for rice growers and consultants and one for County Extension Agents (CEAs), were distributed through e-mail and physical copies in 2020. Thirty-three respondents returned the rice grower (25) and consultant (8) survey representing 26 and seven counties in Arkansas and the Bootheel Missouri area, respectively, as well as four parishes in northeast Louisiana. Eighteen respondents returned the CEA survey. Respondents ranked weedy rice the third most problematic weed in rice, behind Echinochloa spp. and Cyperus spp. The most common infestation levels reported in 78% of fields was less than 12 m−2. Crop rotation (64% growers/consultants, 50% CEAs) and HR rice technology (27% growers/consultants, 50% CEAs) were the top-two most effective methods for weedy rice management, respectively. Tillage and crop rotation practices significantly influenced weedy rice infestation. Rice-soybean [Glycine max (L.) Merr.] rotation had the lowest weedy rice infestation compared to monoculture rice and other crop rotation practices. Crop rotation was not practiced on 26% of reported fields, primarily due to poor drainage. The imidazolinone (IMI)-resistant rice technology was still effective (>70% control) in 60% of fields, but quizalofop-resistant rice is needed to control IMI-resistant weedy rice. Overall, weedy rice remains a challenging weed in rice production.

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