Modified backcross breeding method for rapid conversion of field corn line to shrunken2 (sh2) gene-based sweet corn line

The non-availability of superior and diverse inbred parents is one of the major bottlenecks to develop high yielding sweet corn hybrids. The sh2, one of the promising recessive mutant alleles, has been used in sweet corn development however its transfer to superior field corn lines may require extra inbreeding to identify heterozygous carrier plants. The use of molecular markers linked with sh2 requires a well-equipped laboratory and skilled person to carry the marker assisted backcross breeding (MABB). Considering the above constraints, a modified backcross breeding method was used taking advantage of shrunken kernel of sweet corn for foreground selection coupled with phenotypic comparison with recurrent parent (RP). The BC1F1 plants were grown and plants having high phenotypic similarity with RP were selfed as well as backcrossed as pollen parent. The BC2F1 kernels of BC1F1 plants having high similarity with RP and segregation in BC1F2 kernels were harvested. The BC2F1 plants phenotypically most similar to recomment parameter (RP) were selfed and the shrunken kernels were selected from the segregating BC2F2 .The shrunken kernels were homozygous (sh2sh2) at Sh2 locus, which were validated upon inbreeding based on nonsegregating kernels in BC2F3 . The modified backcross method used is rapid, cost effective and can be used by maize breeder with limited resources for conversion as well diversification of sweet corn germplasm.

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Recovery of Recurrent Parent Genome in a Marker-Assisted Backcrossing Against Rice Blast and Blight Infections Using Functional Markers and SSRs

Plants ◽

10.3390/plants9111411 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1411

Author(s):

Samuel Chibuike Chukwu ◽

Mohd Y. Rafii ◽

Shairul Izan Ramlee ◽

Siti Izera Ismail ◽

Yusuff Oladosu ◽

...

Keyword(s):

Resistance Genes ◽

Blast Resistance ◽

Leaf Blight ◽

Bacterial Leaf Blight ◽

Functional Markers ◽

Recurrent Parent ◽

Selected Lines ◽

Recurrent Parent Genome ◽

Backcross Breeding ◽

Marker Assisted Backcross Breeding

The most vital aspect of marker-assisted backcross breeding is the recurrent parent genome recovery. This enables the selection of only parents with recovered recipient/recurrent parent genome in addition to the targeted genes. The recurrent parent genome recovery (RPGR) ensures that non-desirable genomic segments are removed while the gene of interest is sustained in the recombined progenies without further segregations. This work was aimed at quantifying the RPGR of backcross populations with introgression of bacterial leaf blight resistance genes. Putra-1, a Malaysian elite variety, high yielding with inherent resistance to blast but susceptible to bacterial leaf blight (BLB), was crossed with IRBB60 which is resistant to BLB disease. The IRBB60 has four Xoo resistance genes—Xa4, xa5, xa13 and Xa21. Tightly linked polymorphic functional and SSR markers were used for foreground selection at every stage of backcrossing to select progenies with introgressed target genes. Background selection was done to quantify the percentage of RPGR in the selected lines using 79 confirmed polymorphic microsatellites. Result obtained showed that the percentage of RPGR was 80.11% at BC1F1, 95.30% at BC2F1 and 95.9% at BC2F2. The introgression of Xa4, xa5, xa13 and Xa21 Xoo resistance genes were faster through the adopted marker-assisted backcross breeding compared to what could be obtained through conventional breeding. All the 16 selected lines displayed resistance to BLB with three lines showing high resistance to the disease. The blast resistance contained in the genetic background of Putra-1 was also sustained in all the selected lines. The newly developed lines were recommended as new rice varieties for commercial cultivation.

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Introgression of drought tolerance QTLs through marker assisted backcross breeding in wheat (Triticum aestivum L.)

Indian Journal of Genetics and Plant Breeding (The) ◽

10.31742/ijgpb.80.2.12 ◽

2020 ◽

Vol 80 (02) ◽

Author(s):

Leena Todkar ◽

Harikrishna . ◽

G. P. Singh ◽

Neelu Jain ◽

P. K. Singh ◽

...

Keyword(s):

Drought Tolerance ◽

Agronomic Traits ◽

Wheat Variety ◽

Triticum Aestivum L ◽

Recurrent Parent ◽

Background Selection ◽

Drought Tolerant ◽

Backcross Breeding ◽

Genomic Regions ◽

Marker Assisted Backcross Breeding

The present study reports the introgression of the genomic regions linked with drought tolerance traits viz., NDVI, staygreen, chlorophyll content/chlorophyll fluorescence and yield from a drought tolerant parent HI1500 in to a popular high yielding but drought susceptible wheat variety GW322 following the marker assisted backcross breeding. Background selection with 109 polymorphic SSR markers accelerated genome recovery of recurrent parent which ranged from 72.14 to 86.9% in BC1F1, 90.33 to 92.02% in BC2F1 and 91.6 to 94.95% with an average of 93.5% in BC2F2 generation. Eighteen homozygous BC2F3 progenies were found to be phenotypically superior for morpho-physiological and agronomic traits over the recurrent parent GW322.

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Tolerance of Eight Sweet Corn (Zea mays L.) Hybrids to Pyroxasulfone

HortScience ◽

10.21273/hortsci.43.1.170 ◽

2008 ◽

Vol 43 (1) ◽

pp. 170-172 ◽

Cited By ~ 4

Author(s):

Sarah R. Sikkema ◽

Nader Soltani ◽

Peter H. Sikkema ◽

Darren E. Robinson

Keyword(s):

Zea Mays ◽

Plant Height ◽

Weed Management ◽

Zea Mays L ◽

Sweet Corn ◽

Corn Hybrids ◽

Field Corn

Pyroxasulfone is an experimental herbicide for use in field corn (Zea mays L.) and soybean that may have potential for weed management in sweet corn. Tolerance of eight sweet corn hybrids to pyroxasulfone applied preemergence (PRE) at rates of 0, 209, and 418 g·ha−1 a.i. were studied at two Ontario locations in 2005 and 2006. Pyroxasulfone applied PRE at 209 and 418 g·ha−1 caused minimal (less than 3%) injury in Harvest Gold, GH2041, GH9589, GSS9299, GG214, GG446, GG763, and GG447 sweet corn hybrids at 7, 14, and 28 days after emergence. Pyroxasulfone applied PRE did not reduce plant height, cob size, or yield of any of the sweet corn hybrids tested in this study. Based on these results, pyroxasulfone applied PRE at the rates evaluated can be safely used for weed management in Harvest Gold, GH2041, GH9589, GSS9299, GG214, GG446, GG763, and GG447 sweet corn.

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Marker-Assisted Pyramiding of Downy Mildew-Resistant Gene Ppa3 and Black Rot-Resistant Gene Xca1bo in Popular Early Cauliflower Variety Pusa Meghna

Frontiers in Plant Science ◽

10.3389/fpls.2021.603600 ◽

2021 ◽

Vol 12 ◽

Author(s):

Partha Saha ◽

Chandrika Ghoshal ◽

Namita Das Saha ◽

Aakriti Verma ◽

Mohita Srivastava ◽

...

Keyword(s):

Downy Mildew ◽

Black Rot ◽

Breeding Method ◽

Resistant Gene ◽

Yield And Quality ◽

Resistant Genes ◽

Backcross Breeding ◽

Hybridization Programme ◽

Marker Assisted Backcross Breeding

Cauliflower is an important extensively grown cool season vegetable in India. Black rot and downy mildew are major devastating diseases reducing yield and quality of the crop. To tackle these through host plant resistance, a marker-assisted backcross breeding method was followed to pyramid a black rot-resistant gene (Xca1bo) and a downy mildew-resistant gene (Ppa3) from donors BR-161 and BR-2, respectively, into the background of Pusa Meghna cauliflower cultivar. Marker-assisted backcross breeding was followed up to BC2 generation using SCAR marker ScOPO-04833 and SSR marker BoGMS0624 for black rot and downy mildew resistance genes in foreground selection, respectively. In background selection, at each stage of backcrossing, 47 parental polymorphic SSR markers were used. The graphical genotyping of the five two-gene (Xca1boXca1boPpa3Ppa3) homozygous BC2F2 plants showed an average recovery of 85.44% of the Pusa Meghna genome with highest genome recovery of 91.7%. The genome contribution of donor parents (BR-161 and BR-2) was 8.26 with 6.34% of residual heterozygousity. The backcross derived pyramided lines BC2F2:3-7-16 and BC2F2:3-7-33 showed high resistance to both the diseases and exhibited higher yield and vitamin C content as compared with recipient parent Pusa Meghna. It is, therefore, evident from this study that resistant genes can be introgressed successfully into a Pusa Meghna cultivar without any yield penalty, benefitting farmers with reduced input cost and consumers with chemical residue free produce. Besides, the pyramided lines carrying dominant resistant genes can be exploited in a hybridization programme to develop hybrid(s) in cauliflower.

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Recurrent parent phenome recovery analysis in six different populations with the introgression of genetic male sterile gene ms10 from hot pepper to heat tolerant bell pepper

10.21203/rs.3.rs-643758/v1 ◽

2021 ◽

Author(s):

Menisha Rani ◽

Salesh Kumar Jindal ◽

Om Prakash Meena

Keyword(s):

Fruit Weight ◽

Bell Pepper ◽

Hot Pepper ◽

Recurrent Parent ◽

Male Sterile ◽

Breeding Method ◽

Cross Combination ◽

Successful Recovery ◽

Backcross Breeding ◽

Heat Tolerant

Abstract Backcrossing is one of the most commonly used breeding methods to transfer target trait(s) into a bell pepper inbreds. We attempted for the first time to transfer genetic male sterile (GMS) ms10 gene from the donor parent MS-12, popular GMS line in India, into the genetic background of six heat tolerant bell pepper inbreds, in restricted generations through the marker-assisted selection (MAS) and backcross breeding method, to develop new GMS lines in bell pepper. In this project, the recurrent parent phenome (RPP) recovery was analyzed in each generations of backcrossing using economic phenotypic markers. Phenotypic background analysis revealed that the extent of RPP recovery ranged from 43.59% (MSSM-1) to 66.26% (MSSM-21) and 70.89% (MSSM-17) to 92.09% (MSSM-21) for fruit weight, from 19.0% (MSSM-21) to 55.14% (MSSM-3) and 61.0% (MSSM-21) to 98.75% (MSSM-1) for number of lobes fruit− 1, from 55.77% (MSSM-17) to 94.25% (MSSM-2) and 69.83% (MSSM-17) to 98.26% (MSSM-3) for total fruit yield plant− 1 in BC1F1 and BC2F1 populations, respectively. Based on a paired 't' test analysis in BC2F1 population, out of six, the MSSM-1 and MSSM-2 generation was shown to be non-significant for all 19 studied traits followed by MSSM-3 (18), indicating a successful recovery of the recipient genome through marker-assisted backcross breeding after successful introgression of the ms10 gene. The GMS lines developed from this project will be utilized in bell pepper breeding programs aimed to identify the best cross-combination for their cultivation under north-Indian plains.

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Introgression of qDTY1.1 Governing Reproductive Stage Drought Tolerance into an Elite Basmati Rice Variety “Pusa Basmati 1” through Marker Assisted Backcross Breeding

Agronomy ◽

10.3390/agronomy11020202 ◽

2021 ◽

Vol 11 (2) ◽

pp. 202

Author(s):

Gaurav Dhawan ◽

Aruna Kumar ◽

Priyanka Dwivedi ◽

Subbaiyan Gopala Krishnan ◽

Madan Pal ◽

...

Keyword(s):

Drought Stress ◽

Reproductive Stage ◽

Chromosome 1 ◽

Basmati Rice ◽

Yield Potential ◽

Yield Reduction ◽

Recurrent Parent ◽

Backcross Breeding ◽

Selection For ◽

Marker Assisted Backcross Breeding

Drought stress at the reproductive stage in rice is one of the most important cause for yield reduction, affecting both productivity and quality. All Basmati rice varieties, including the popular cultivar “Pusa Basmati 1 (PB1)” is highly sensitive to reproductive stage drought stress (RSDS). We report for the first time, improvement of a Basmati cultivar for RSDS tolerance, with the introgression of a major quantitative trait locus (QTL), “qDTY1.1” into PB1. The QTL was sourced from an aus variety, Nagina 22 (N22). A microsatellite (simple sequence repeat (SSR)) marker “RM 431” located at telomeric end (38.89 mb) of chromosome 1, and located within a 1.04 mb QTL region was employed for foreground selection for qDTY1.1 in the marker assisted backcross breeding process. A set of 113 SSR markers polymorphic between N22 and PB1 were utilized for background selection to ensure higher recurrent parent genome recovery. After three backcrosses followed by five generations of selfing, eighteen near isogenic lines (NILs) were developed, through combinatory selection for agro-morphological, grain and cooking quality traits. The NILs were evaluated for three consecutive Kharif seasons, 2017, 2018 and 2019 under well-watered and drought stress conditions. RSDS tolerance and yield stability indicated that P1882-12-111-3, P1882-12-111-5, P1882-12-111-6, P1882-12-111-7, P1882-12-111-12, P1882-12-111-15 and P1882-12-111-17 were best in terms of overall agronomic and grain quality under RSDS. Additionally, NILs exhibited high yield potential under normal condition as well. The RSDS tolerant Basmati NILs with high resilience to water stress, is a valuable resource for sustaining Basmati rice production under water limiting production environments.

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Response of Eight Sweet Corn (Zea mays L.) Hybrids to Topramezone

HortScience ◽

10.21273/hortsci.42.1.110 ◽

2007 ◽

Vol 42 (1) ◽

pp. 110-112 ◽

Cited By ~ 9

Author(s):

Nader Soltani ◽

Peter H. Sikkema ◽

John Zandstra ◽

John O'Sullivan ◽

Darren E. Robinson

Keyword(s):

Zea Mays ◽

Plant Height ◽

Weed Management ◽

Zea Mays L ◽

Sweet Corn ◽

Marketable Yield ◽

Corn Hybrids ◽

Field Corn ◽

Initial Sensitivity

Topramezone is a newly introduced herbicide for use in field corn (Zea mays L.) that may have potential for weed management in sweet corn. Tolerance of eight sweet corn hybrids to topramezone applied postemergence (POST) at 0, 50, 75, 100, 150, and 300 g a.i. ha− 1 were studied at one Ontario location in 2000 and two locations in 2001 and 2002. Topramezone applied POST at 50, 75, 100, and 150 g·ha− 1 did not cause any visual injury in Calico Belle, CNS 710, Delmonte 2038, FTF 222, FTF 246, GH 2684, Reveille, and Rival sweet corn hybrids at 7 days after treatment (DAT) and caused minimal injury (less than 5%) at 300 g·ha− 1 in all hybrids. The initial sensitivity observed in these hybrids was minimal and transient with no effect on visual injury at 14 and 28 DAT. Topramezone applied POST did not reduce plant height, cob size, or marketable yield of the sweet corn hybrids included in this study. Based on these results, topramezone applied POST at the rates evaluated can be safely applied to Calico Belle, CNS 710, Delmonte 2038, FTF 222, FTF 246, GH 2684, Reveille, and Rival sweet corn.

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072 Backcross Breeding with RAPD Molecular Markers to Enhance Resistance to Common Bacterial Blight in Pinto Beans

HortScience ◽

10.21273/hortsci.34.3.453e ◽

1999 ◽

Vol 34 (3) ◽

pp. 453E-453

Author(s):

N. Mutlu ◽

D.P. Coyne ◽

S.O. Park ◽

J.R. Steadman

Keyword(s):

Molecular Markers ◽

Bacterial Blight ◽

Xanthomonas Campestris ◽

Coat Color ◽

Flower Color ◽

Recurrent Parent ◽

Common Bacterial Blight ◽

Breeding Method ◽

Backcross Breeding ◽

Moderate Resistance

Common bacterial blight (CBB) in common bean (Phaseolus vulgaris L.), caused by Xanthomonas campestris pv. phaseoli (Xcp), reduces bean yields and quality throughout the world. Pinto `Chase' is a high-yielding variety with moderate resistance to Xcp derived from great northern Nebraska #1 selection 27, whose resistance is derived from an unknown tepary (P. acutifolius) bean source. XAN-159 is a black mottled small seeded breeding line with different genes for high resistance to Xcp derived from a different tepary source (PI 319443). Our objective was to pyramid different genes for Xcp resistance from the donor parent XAN-159 into the rust-resistant recurrent parent Pinto `Chase' using the classical back-cross breeding method with confirmation of resistance using RAPD molecular markers. Resistance was confirmed in some BC2F2 generation plants. Seven RAPD markers and the V locus (flower color) previously identified were confirmed in the BC1 and BC2 populations. Smaller seed size, purple flower color, and black mottled seed coat color were coinherited with resistance to Xcp. However, a recombinant plant with enhanced CBB resistance and moderate-sized pinto seed was identified. Backcross breeding is being continued.

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Marker-Assisted Backcross Breeding for Improvement of Submergence Tolerance and Grain Yield in the Popular Rice Variety ‘Maudamani’

Agronomy ◽

10.3390/agronomy11071263 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1263

Author(s):

Elssa Pandit ◽

Swapnil Pawar ◽

Saumya Ranjan Barik ◽

Shakti Prakash Mohanty ◽

Jitendriya Meher ◽

...

Keyword(s):

Grain Yield ◽

Rice Variety ◽

Yield Component ◽

Submergence Tolerance ◽

Breeding Method ◽

Submergence Stress ◽

Backcross Breeding ◽

Grain Width ◽

Marker Assisted Backcross Breeding ◽

Recipient Parent

Submergence stress due to flash floods reduces rice yield drastically in sensitive varieties. Maudamani is a high yielding popular rice variety but is highly susceptible to submergence stress. The selection of progenies carrying Sub1 and GW5 (wide-grain) enhanced the submergence stress tolerance and grain yield of theMaudamani variety by following the marker-assisted backcross breeding method. Foreground screening detected 14 BC1F1, 17 BC2F1, and 12 BC3F1 backcross progenies that carried the target QTLs for submergence tolerance and grain width. Background screening was performed in the progenies carrying the target QTL and enhanced the recovery of a recipient parent’s genome by upto 96.875% in the BC3 pyramided line. The BC3F1 plant containing the highest recipient parent genome content and the target QTLs was self-pollinated. In BC3F2 generation, the target QTLs the Sub1 and GW5 (wide-grain) alleles and recipient parent’s yield component QTL OsSPL14 were tracked for homozygous states in the progenies. Seven pyramided lines showed tolerance to submergence for 14 days and higher grain yield than both the parents. The pyramided lines were similar to the recipient parent for the majority of the studied morphological and quality traits. The pyramided lines are useful as cultivars and can serve as potential donors for transfer of Sub1, OsSPL14, Gn1a, GW5 (wide-grain), and SCM2 QTLs.

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Introgression of submergence tolerance into CO 43, a popular rice variety of India, through marker-assisted backcross breeding

Czech Journal of Genetics and Plant Breeding ◽

10.17221/149/2017-cjgpb ◽

2018 ◽

Vol 54 (No. 3) ◽

pp. 101-108 ◽

Cited By ~ 4

Author(s):

Rahman Hifzur ◽

Dakshinamurthi Vijayalakshmi ◽

Ramasamy Sasikala ◽

Manickam Sudha ◽

Kaliyaperumal Ashok Kumar ◽

...

Keyword(s):

Rice Variety ◽

Recurrent Parent ◽

South East Asia ◽

Submergence Tolerance ◽

Early Generation ◽

Rice Varieties ◽

Major Threat ◽

Backcross Breeding ◽

Marker Assisted Backcrossing ◽

Marker Assisted Backcross Breeding

Submergence is a major threat in rice growing areas of South and South-East Asia. Identification of a major QTL, Sub1 and advancements in marker-assisted backcrossing strategy enabled breeders to develop submergence tolerant versions of popular rice cultivars. In the present study, a marker-assisted backcross breeding (MABB) approach was used to introgress the Sub1 locus from the tolerant FR13A variety into CO 43, one of the popular rice varieties of southern India. Evaluation of early generation segregating progenies derived from the cross of CO 43 and FR13A revealed the introgression of Sub1, leading to increased tolerance to submergence and better revival ability after it. Genotyping and phenotyping of BC<sub>3</sub>F<sub>3</sub> generation resulted in elite NILs of CO 43 harbouring Sub1 the locus and possessing 94.37% and 95.78% of the recurrent parental CO 43 genome. Selected NILs performed equal as the recurrent parent CO 43 under normal conditions, but were more tolerant to submergence and revived better, afterwards. Under flooding NILs yielded about 25–30% higher than the recurrent parent CO 43.

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