Development of herbicide-tolerant irrigated rice cultivars

The objective of this work was to develop new irrigated rice lines tolerant to imidazolinone herbicides. The backcross breeding procedure was used to transfer the imidazolinone tolerance allele from mutant 93AS3510 to the recurrent parents 'BRS 7 Taim' and 'BRS Pelota'. Individual herbicide-tolerant plants were selected in each generation, for three backcrossings (RC1 to RC3), followed by three selfing generations (RC3F1 to RC3F3). The best four RC3F3 lines for agronomic traits were genotyped with 44 microsatellite markers. The observed conversion index of the new imidazolinone-tolerant lines varied from 91.86 to 97.67%. Pairwise genetic distance analysis between these lines and 22 accessions from the Embrapa's Rice Germplasm Bank clustered the new lines with their respective recurrent parents, but not with 'IRGA 417', which was originally used as recurrent parent to derive IRGA 422 CL, the only imidazolinone-tolerant irrigated rice cultivar recommended for cultivation in Brazil. Therefore, these lines represent new options of genetically diverse imidazolinone-tolerant rice accessions. Lines CNA10756 ('BRS Sinuelo CL') and CNA10757 will be released for cultivation in the Clearfield irrigated rice production system in Rio Grande do Sul, Brazil.

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Marker-Assisted Introgression of Saltol QTL Enhances Seedling Stage Salt Tolerance in the Rice Variety “Pusa Basmati 1”

International Journal of Genomics ◽

10.1155/2018/8319879 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 18

Author(s):

Vivek Kumar Singh ◽

Brahma Deo Singh ◽

Amit Kumar ◽

Sadhna Maurya ◽

Subbaiyan Gopala Krishnan ◽

...

Keyword(s):

Salt Tolerance ◽

Ssr Markers ◽

Agronomic Traits ◽

Rice Variety ◽

Crop Improvement ◽

Rice Cultivar ◽

Seedling Stage ◽

Basmati Rice ◽

Recurrent Parent ◽

Foreground Selection

Marker-assisted selection is an unequivocal translational research tool for crop improvement in the genomics era. Pusa Basmati 1 (PB1) is an elite Indian Basmati rice cultivar sensitive to salinity. Here, we report enhanced seedling stage salt tolerance in improved PB1 genotypes developed through marker-assisted transfer of a major QTL, Saltol. A highly salt tolerant line, FL478, was used as the Saltol donor. Parental polymorphism survey using 456 microsatellite (SSR)/QTL-linked markers revealed 14.3% polymorphism between PB1 and FL478. Foreground selection was carried out using three Saltol-linked polymorphic SSR markers RM8094, RM493, and RM10793 and background selection by 62 genome-wide polymorphic SSR markers. In every backcross generation, foreground selection was restricted to the triple heterozygotes of foreground markers, which was followed by phenotypic and background selections. Twenty-four near isogenic lines (NILs), with recurrent parent genome recovery of 96.0–98.4%, were selected after two backcrosses followed by three selfing generations. NILs exhibited agronomic traits similar to those of PB1 and additional improvement in the seedling stage salt tolerance. They are being tested for per se performance under salt-affected locations for release as commercial varieties. These NILs appear promising for enhancing rice production in salinity-affected pockets of Basmati Geographical Indication (GI) areas of India.

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Interaction between saflufenacil and imazapyr+imazapic in the management of barnyardgrass and weedy rice and selectivity for irrigated rice

Ciência Rural ◽

10.1590/0103-8478cr20190821 ◽

2020 ◽

Vol 50 (7) ◽

Author(s):

Ânderson da Rosa Feijó ◽

Marcus Vinicius Fipke ◽

Luiza Piccinini Silveira ◽

Edinalvo Rabaioli Camargo ◽

Nelson Diehl Kruse ◽

...

Keyword(s):

Weed Control ◽

Field Experiments ◽

Rice Cultivar ◽

Weedy Rice ◽

Rice Cultivars ◽

Irrigated Rice ◽

Growing Seasons ◽

Herbicide Treatments ◽

Imidazolinone Herbicides ◽

Chemical Groups

ABSTRACT: The use of imidazolinone-tolerant rice cultivars allows selective control of weedy rice and barnyardgrass. However, in many situations, there is a need to add herbicides from other chemical groups to increase the spectrum of weed control. In this sense, saflufenacil has the potential to be used in mixture with imidazolinone herbicides. This study aimed to evaluate the interaction effects of the imazapyr+imazapic and saflufenacil herbicides in weedy rice and barnyardgrass and to investigate their impacts on the yield of the irrigated rice cultivar Puitá INTA CL. To reach these aims, greenhouse and field experiments were carried out during two growing seasons, with herbicide treatments sprayed separately and in mixtures of saflufenacil with imazapyr+imazapic. Results showed that saflufenacil did not interfere with control of weedy rice and barnyardgrass obtained with imazapyr+imazapic. The D50 values of imazapyr+imazapic for weedy rice control were 14.5+5, 9.1+3 and 12.5+4.2 g ha-1of imazapyr+imazapic for combinations with 0, 3.06 and 6.12 g ha-1of saflufenacil, respectively. In the field experiments, all doses of imazapyr+imazapic applied isolated or in mixture with saflufenacil provided control levels barnyardgrass above 90% at 28 days after herbicides application. Furthermore, saflufenacil did not cause damage or loss in the yield of the rice crop when mixed with imazapyr+imazapic. The Puitá INTA CL rice cultivar was tolerant of the tested herbicides, whether applied alone or in mixture, reaching grain yield of 9.987 kg ha-1 when applied 42 g ha-1 of saflufenacil plus 147+49 g ha-1 of imazapyr+imazapic.

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Genetic distance analysis among nine endogamous population groups of Maharashtra, India

Journal of Human Evolution ◽

10.1016/0047-2484(79)90107-6 ◽

1979 ◽

Vol 8 (6) ◽

pp. 567-570 ◽

Cited By ~ 10

Author(s):

B.N. Mukherjee ◽

P.P. Majumder ◽

K.C. Malhotra ◽

S.K. Das ◽

S.L. Kate ◽

...

Keyword(s):

Genetic Distance ◽

Population Groups ◽

Distance Analysis ◽

Endogamous Population ◽

Genetic Distance Analysis

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Leaching and residual activity of imidazolinone herbicides in lowland soils

Ciência Rural ◽

10.1590/0103-8478cr20160705 ◽

2017 ◽

Vol 47 (5) ◽

Cited By ~ 5

Author(s):

João Paulo Refatti ◽

Luis Antonio de Avila ◽

José Alberto Noldin ◽

Igor Pacheco ◽

Rodrigo Ribeiro Pestana

Keyword(s):

Oryza Sativa L ◽

Residual Activity ◽

Underground Water ◽

Soil Samples ◽

Treatment Control ◽

Irrigated Rice ◽

Leaching Potential ◽

Phytotoxic Activity ◽

Lowland Area ◽

Imidazolinone Herbicides

ABSTRACT: Herbicides used in the Clearfield® rice (Oryza sativa L.) production system have a potential for leaching. This can result in contamination of underground water resources and cause injury to not tolerant crops that are sown in a succession and/or crop rotation. The objective of this study was to determine the leaching potential and the residual activity of the herbicides used in the Clearfield® rice system. The experiment was conducted over a period of two years and consisted of conducting a field test to be followed by two bioassays with a year of difference between their implementation. Initially an experiment was conducted in lowland area where it was planted the cultivar of rice ‘PUITA INTA CL’. Approximately one and two years thereafter, soil samples from each plot were collected at intervals of 5cm to a depth of 30cm (B factor) for the bioassay to evaluate persistence of herbicides. Factor A was composed of mixtures formulated of imazethapyr + imazapic (75 + 25g a.i. L-1), imazapyr + imazapic (525 + 175g a.i. kg-1) in two doses, imazethapyr (100g a.i. L-1) and treatment control without application. Basing on results, it was concluded that the mixtures imazethapyr + imazapic, imazapyr + imazapic and imazethapyr leached into the soil, reaching depths of up to 25cm in lowland soil. Imidazolinone herbicides used today in the irrigated rice Clearfield® system are persistent in soil, and their phytotoxic activity can be observed up to two years after application.

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ANTAGONISM IS THE PREDOMINANT EFFECT OF HERBICIDE MIXTURES USED FOR IMIDAZOLINONE-RESISTANT BARNYARDGRASS (Echinochloa crus-galli) CONTROL

Planta Daninha ◽

10.1590/s0100-83582015000300021 ◽

2015 ◽

Vol 33 (3) ◽

pp. 587-597 ◽

Cited By ~ 6

Author(s):

F. O. MATZENBACHER ◽

A. KALSING ◽

G. DALAZEN ◽

C. MARKUS ◽

A. MEROTTO JR

Keyword(s):

Weed Control ◽

Rice Grain ◽

Irrigated Rice ◽

Antagonistic Effects ◽

Adequate Knowledge ◽

Herbicide Mixtures ◽

Als Inhibitors ◽

Imidazolinone Herbicides ◽

Predominant Effect ◽

Major Target

ABSTRACTHerbicides mixtures are used in many situations without the adequate knowledge related with the effect on major target weeds. The objective of this study was to evaluate the effects of different herbicides mixtures used in irrigated rice in order to establish the adequate combinations for the prevention and management of herbicide resistance in barnyardgrass (Echinochloa crus-galli). Three experiments were performed at field conditions with all major post-emergent herbicides used in irrigated rice in Brazil. The first experiment was performed with barnyardgrass resistant to imidazolinone herbicides and herbicides applied at label rates. The second and third experiments were performed with barnyardgrass resistant and susceptible to imidazolinone herbicides applied at doses of 50 or 75% of the label rates. The occurrence of additive, synergistic and antagonistic effects was identified at 18, 18 and 64%, respectively, among the total of 50 different associations of herbicide and rates evaluated. In general, the mixture of ACCase inhibitors with ALS inhibitors, quinclorac, clomazone + propanil or thiobencarb resulted in antagonism. Sinergic mixtures were found in clomazone with propanil + thiobencarb, profoxydim with cyhalofop-butyl or clomazone, and quinclorac with imazapyr + imazapic, bispyribac-sodium or cyhalofop-butyl. The mixtures of quinclorac with profoxydim were antagonic. Rice grain yield varied according to the efficiency of weed control. Seveveral mixtures were effective for imidazolinone resistant barnyardgrass control.

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Establishment of the irrigated rice cultivar SCSBRS Tio Taka by recurrent selection

Cropp Breeding and Applied Biotechnology ◽

10.12702/1984-7033.v07n01a17 ◽

2007 ◽

Vol 7 (1) ◽

pp. 103-110 ◽

Cited By ~ 7

Author(s):

P.H.N. Rangel ◽

C. Brondani ◽

O.P. Morais ◽

M.A. Schiocchet ◽

T.C.O. Borba ◽

...

Keyword(s):

Recurrent Selection ◽

Rice Cultivar ◽

Irrigated Rice

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Morphoagronomic characterization of sweet potato accessions from the germplasm bank of Embrapa hortaliças

Bioscience Journal ◽

10.14393/bj-v35n6a2019-42434 ◽

2019 ◽

Vol 35 (6) ◽

Author(s):

Rosa maria de Deus De Sousa ◽

José Ricardo Peixoto ◽

Geovani Bernardo Amaro ◽

Michelle Sousa Vilela ◽

Paula Andrea Osorio Carmona

Keyword(s):

Sweet Potato ◽

Ipomoea Batatas ◽

Agronomic Traits ◽

Block Design ◽

Branch Length ◽

Leaf Color ◽

Germplasm Bank ◽

Immature Leaf ◽

Productive Potential ◽

Branch Weight

Studies on the determination of genetic divergence among genotypes are important tools in breeding programs, contributing to the identification of parents with considerable productive potential. However, little is known about the combinatorial capacity of sweet potato (Ipomoea batatas) accessions and its adaptation to the different regions of Brazil. The objective of this study was to evaluate the morpho-agronomic traits from 102 sweet potato accessions from the Germplasm Bank of Embrapa Hortaliças. The experiment was laid out as an augmented block design comprised of 102 treatments. Nineteen above ground traits were measured using descriptors for the respective parts. Estimated values of broad sense heritability were high for the traits mean branch length (95.75%), immature leaf color (85.06%), and predominant branch color (90.57%). Coefficients of environmental variation were below 30.00% for all variables, except for branch weight (51.62%). The 102 clones analyzed presented broad genetic variability for the different traits evaluated, especially for branch weight, and branch length, and mature leaf color.

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Whole Genome Characterization and Genetic Evolution Analysis of a New Ostrich Parvovirus

Viruses ◽

10.3390/v12030334 ◽

2020 ◽

Vol 12 (3) ◽

pp. 334

Author(s):

Kunpeng Yuan ◽

Dongdong Wang ◽

Qingdong Luan ◽

Ju Sun ◽

Qianwen Gao ◽

...

Keyword(s):

Comprehensive Analysis ◽

Open Reading Frames ◽

Genome Characterization ◽

Distance Analysis ◽

Evolution Analysis ◽

New Information ◽

Close Relationship ◽

Goose Parvovirus ◽

Genetic Distance Analysis ◽

Reading Frames

Ostrich diseases characterized by paralysis have been breaking out in broad areas of China since 2015, causing major damage to the ostrich breeding industry in China. This report describes a parvovirus detected in ostriches from four different regions. The entire genomes of four parvovirus strains were sequenced following amplification by PCR, and we conducted comprehensive analysis of the ostrich parvovirus genome. Results showed that the length genomes of the parvovirus contained two open reading frames. Ostrich parvovirus (OsPV) is a branch of goose parvovirus (GPV). Genetic distance analysis revealed a close relationship between the parvovirus and goose parvovirus strains from China, with the closest being the 2016 goose parvovirus RC16 strain from Chongqing. This is the first report of a parvovirus in ostriches. However, whether OsPV is the pathogen of ostrich paralysis remains uncertain. This study contributes new information about the evolution and epidemiology of parvovirus in China, which provides a new way for the study of paralysis in ostriches.

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Genetic Differentiation in Moroccan Opuntia ficus-indica Cultivars Using Simple Sequence Repeat (SSR) Markers

Notulae Scientia Biologicae ◽

10.15835/nsb839864 ◽

2016 ◽

Vol 8 (3) ◽

pp. 380-385 ◽

Cited By ~ 1

Author(s):

Aissam EL FINTI ◽

Driss TALIBI ◽

Mouhamed SIDKI ◽

Abdelhamid E. MOUSADIK

Keyword(s):

Genetic Diversity ◽

Genetic Differentiation ◽

Ssr Markers ◽

Opuntia Ficus Indica ◽

Distance Analysis ◽

Reference Collection ◽

Ssr Loci ◽

Set Up ◽

Genetic Distance Analysis ◽

Simple Sequence

Estimation of genetic parameters at SSR loci can be applied for assessing the differences between cultivars or populations, either for variety distinction or the management of genetic resources. In this study, 13 Opuntia ficus-indica cultivars were analyzed using 10 SSR markers selected for studying the genetic diversity among these chosen cultivars. Over the 10 SSR markers, a total of 45 reproducible bands were scored with an average of 4.5 alleles/locus, while the observed heterozygosity (Ho) values of amplified loci ranged from 0.15 (SSR1) to 0.92 (SSR2 and SSR 11). Genetic distance analysis of the 13 cultivars showed a large genetic differentiation (GST = 0.47) and high number of different groups. Most of the accessions were not found to be clustered according to their eco-geographical origin. In addition, each cultivar was characterized by its own multiallelic combination between loci. The results revealed the usefulness of SSR in understanding of genetic diversity in Moroccans Barbary fig cultivars, thus being helpful to set up rational decisions concerning the establishment of a national reference collection.

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Effect of Furrow Irrigation on the Severity of False Smut in Susceptible Rice Varieties

Plant Disease ◽

10.1094/pdis-94-5-0570 ◽

2010 ◽

Vol 94 (5) ◽

pp. 570-574 ◽

Cited By ~ 16

Author(s):

Steven A. Brooks ◽

Merle M. Anders ◽

Kathleen M. Yeater

Keyword(s):

Agricultural Practices ◽

Rice Cultivar ◽

Effective Field ◽

Field Resistance ◽

Southern United States ◽

Rice Cultivars ◽

Rice Varieties ◽

Irrigated Rice ◽

Ustilaginoidea Virens ◽

False Smut

False smut (Ustilaginoidea virens) is an important emerging disease of rice (Oryza sativa) in the southern United States, where all major rice cultivars and hybrids are susceptible to the disease. False smut susceptibility was evaluated in traditional paddy-rice fields and under furrow-irrigated conditions to determine the effects of alternative agricultural practices on the severity of this disease. Highly effective false smut suppression was observed in furrow-irrigated rice, where the disease was nearly eliminated in susceptible rice entries. False smut suppression was observed for two hybrids and one conventional rice cultivar, demonstrating that suppression was not limited to specific germplasm sources. Kernel smut severity was also monitored, but no effect on this disease was observed from the irrigation treatments. Therefore, suppression of disease severity in nonflooded rice appears to be a phenomenon unique to the rice–false smut pathosystem, which can be exploited to achieve effective field resistance to this disease.

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