A Review of Microsatellite Markers and Their Applications in Rice Breeding Programs to Improve Blast Disease Resistance

Abstract Background: The molecular mechanism of durable and broad-spectrum resistance to rice blast disease in japonica rice variety is still very little known. Ziyu44, a local japonica rice variety in Yunnan Province of China, has shown durable broad-spectrum blast resistance for more than 30 years, and provides an opportunity for us to explore the molecular basis of broad-spectrum resistance to rice blast in japonica rice variety.Methods and Results: We conducted a comparative study of mycelium growth, aposporium formation, the accumulation of salicylate(SA), jasmonate(JA) and H2O2, the expression of SA- and JA-associated genes between Ziyu44 and susceptible variety Jiangnanxiangnuo (JNXN) upon M. oryzae infection. We found that appressorium formation and invasive hyphae extention were greatly inhibited in Ziyu 44 leaves compared with that in JNXN leaves. Both Ziyu 44 and JNXN plants maintained high levels of baseline SA and did not show increased accumulation of SA after inoculation with M. oryzae, while the levels of baseline JA in Ziyu 44 and JNXN plants were relatively low, and the accumulation of JA exhibited markedly increased in Ziyu 44 plants upon M. oryzae infection. The expression levels of key genes involving JA and SA signaling pathway OsCOI1b, OsNPR1, OsMPK6 as well as pathogenesis-related (PR) genes OsPR1a, OsPR1b and OsPBZ1, were markedly up-regulated in Ziyu44. Conclusions: The level of endogenous JA is critical for synchronous activation of SA and JA signaling pathway, up-regulating PR gene expression and enhancing disease resistance against rice blast in Ziyu44.

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Review: Genetic diversity studies using microsatellite markers and their contribution in supporting sustainable sheep breeding programs

Asian Journal of Agriculture ◽

10.13057/asianjagric/g010109 ◽

2017 ◽

Vol 1 (01) ◽

pp. 46-51

Author(s):

OUMER SHERIFF ◽

KEFYALEW ALEMAYEHU

Keyword(s):

Genetic Diversity ◽

Microsatellite Markers ◽

Polymorphic Information Content ◽

Domestic Sheep ◽

Breeding Programs ◽

Sheep Breeding ◽

Population Structures ◽

The Mean ◽

Tree Building ◽

Diversity Studies

Sheriff O, Alemayehu K. 2017. Review: Genetic diversity studies using microsatellite markers and their contribution in supporting sustainable sheep breeding programs. Asian J Agric 1: 46-51. Microsatellites have been widely accepted and employed as useful molecular markers for measuring genetic diversity and divergence within and among populations. The various parameters developed so far to measure genetic diversity within and among populations are observed and expected heterozygosities (Ho and He), the mean number of alleles per locus (MNA),polymorphic information content (PIC), genetic distance and phylogenetic or tree building approach.The objective of thisreview was therefore to quantifythe genetic diversity studies of domestic sheep populations using microsatellite markersand their contribution in supporting sustainable sheep breeding programs. From the review, it is possible to see that there was high within population genetic variations in all the studied sheep populations, poor level of population differentiations and high levels of inbreeding. On the other hand, low estimates of hetrozygosities and mean number of alleles and employing only few and weak markers were observed in some of the studies. The gaps observed in the previous genetic diversity studies of the sheep populations may demand further works to reveal more information on the population structures andto start appropriate and sustainable breeding programs.

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Prospects of breeding for blast disease resistance in the oil palm (Elaeis guineensis Jacq.)

Euphytica ◽

10.1007/bf00035685 ◽

1969 ◽

Vol 18 (2) ◽

pp. 153-156

Author(s):

G. Blaak

Keyword(s):

Disease Resistance ◽

Oil Palm ◽

Elaeis Guineensis ◽

Blast Disease ◽

Elaeis Guineensis Jacq

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Molecular Markers for Powdery Mildew in Pea (Pisum sativum L.): A Review

Legume Research - An International Journal ◽

10.18805/lr-4740 ◽

2021 ◽

Author(s):

Reginah Pheirim ◽

Noren Singh Konjengbam ◽

Mayurakshee Mahanta

Keyword(s):

Disease Resistance ◽

Powdery Mildew ◽

Powdery Mildew Resistance ◽

Genetic Resistance ◽

Disease Resistance Gene ◽

Breeding Programs ◽

Biotic Stresses ◽

Pisum Sativum L ◽

Development And Utilization ◽

Mapping Populations

Powdery mildew is caused by an obligate parasite Erysiphe pisi and considered as one of the most important constraints causing yield reductions in pea. Development and utilization of genetic resistance is acknowledged as the most effective, economic and environmental friendly method of control. Therefore, development of cultivars with improved resistance to biotic stresses is a primary goal of plant breeding programs throughout the world. Three monogenic sources er1, er2 and Er3 have been described to govern the powdery mildew disease resistance. Several markers have been reported linked to resistant genes at varying distances in different mapping populations. Genetic markers linked to the disease resistance gene make the breeding process more efficient for the use of Marker Assisted Selection (MAS) strategy to aid in obtaining a complete powdery mildew resistance in pea.

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Genetic selection for improved disease resistance in aquaculture with special reference to shrimp and tilapia breeding programs in Egypt

Journal of Applied Aquaculture ◽

10.1080/10454438.2019.1697783 ◽

2019 ◽

Vol 32 (4) ◽

pp. 291-340

Author(s):

Mohamed E. Megahed

Keyword(s):

Disease Resistance ◽

Special Reference ◽

Genetic Selection ◽

Breeding Programs ◽

Selection For

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Combining Ability Analysis of Blast Disease Resistance and Agronomic Traits in Finger Millet [Eleusine coracana (L.) Gaertn]

Journal of Agricultural Science ◽

10.5539/jas.v8n11p138 ◽

2016 ◽

Vol 8 (11) ◽

pp. 138 ◽

Cited By ~ 1

Author(s):

Lawrence Owere ◽

Pangirayi Tongoona ◽

John Derera ◽

Nelson Wanyera

Keyword(s):

Disease Resistance ◽

Combining Ability ◽

Finger Millet ◽

Gene Action ◽

Agronomic Traits ◽

The Other ◽

Blast Disease ◽

Additive Gene Action ◽

Gene Effects ◽

Additive Gene

Blast disease is the most important biotic constraint to finger millet production. Therefore disease resistant varieties are required. However, there is limited information on combining ability for resistance and indeed other agronomic traits of the germplasm in Uganda. This study was carried out to estimate the combining ability and gene effects controlling blast disease resistance and selected agronomic traits in finger millet. Thirty six crosses were generated from a 9 × 9 half diallel mating design. The seed from the 36 F1 crosses were advanced by selfing and the F2 families and their parents were evaluated in three replications. General combining ability (GCA) for head blast resistance and the other agronomic traits were all highly significant (p ≤ 0.01), whereas specific combining ability (SCA) was highly significant for all traits except grain yield and grain mass head-1. On partitioning the mean sum of squares, the GCA values ranged from 31.65% to 53.05% for head blast incidence and severity respectively, and 36.18% to 77.22% for the other agronomic traits measured. Additive gene effects were found to be predominant for head blast severity, days to 50% flowering, grain yield, number of productive tillers plant-1, grain mass head-1, plant height and panicle length. Non-additive gene action was predominant for number of fingers head-1, finger width and panicle width. The parents which contributed towards high yield were Seremi 2, Achaki, Otunduru, Bulo and Amumwari. Generally, highly significant additive gene action implied that progress would be made through selection whereas non-additive gene action could slow selection progress and indicated selection in the later generations.

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