Record Details

MAPPING OF GENE(S) FOR RESISTANCE TO POST FLOWERING STALK ROT IN MAIZE (Zea mays L.) CAUSED BY Macrophomina phaseolina (Tassi) Goid.

KrishiKosh

View Archive Info
 
 
Field Value
 
Title MAPPING OF GENE(S) FOR RESISTANCE TO POST FLOWERING STALK ROT IN MAIZE (Zea mays L.) CAUSED BY Macrophomina phaseolina (Tassi) Goid.
 
Creator SUNEETHA, P
 
Contributor ANURADHA, G
 
Subject vegetables, plant oils, pesticides, sampling, confectionery, maize, pesticide residues, monocrotophos, markets, fruits
 
Description Among major cereal crops in production, maize (Zea mays L.) is the world’s third leading crop after wheat and rice grown in different agro-ecologies of the world. It has highest genetic yield potential amongst the cereal crops. 67% of maize is used for live stock feed and 25% of maize for human consumption, industrial purposes and the balance is used as seed. Diseases are one of the major constraints in realizing the potential yield of this crop. It suffers from number of diseases on a global basis.
In India there are four downy mildews, four stalk rots, three foliar diseases, root rots and other diseases affecting kernel and other aerial parts. Disease spectrum varies in different agro climatic zones. More serious diseases are leaf blight, stalk rots, downy mildews and rusts. Post flowering stalk rot complex is one of the most serious, destructive and widespread group of diseases in maize and yield losses range from 10 to 42% and can be as high as 100% in some areas. Stalk rots take a heavy toll, among which stalk rots caused by Macrophomina phaseolina (Tassi) Goid. and Fusarium moniliforme results in 30-40% losses. Post flowering stalk rot (PFSR) is the complex disease caused by three fungi,viz., Cephalosporium acremonium, Macrophomina phaseolina (Tassi) Goid., Fusarium moniliforme and one bacterium Erwinia carotovora var zeae. Out of these, post flowering stalk rot caused by Macrophomina phaseolina (Tassi) Goid is the important disease of maize in the state of Andhra Pradesh.
The most promising and cheapest way to control stalk rot disease might be through growing resistant lines. Application of molecular markers play an important role in identifying pest/disease resistant cultivar through already available designed marker (MAS). Though mapping of genes for resistance to PFSR caused by M.phaseolina was carried out, very small attempt was made to identify markers linked to resistance to PFSR caused by M.phaseolina (Tassi) Goid. through BSA in F2 population developed from cross involving BPPTI66 and BPPTI34.The present investigation was to confirm the marker identified involving different set of parents and
further to map the gene for resistance to PFSR caused by M.phaseolina and also to validate the marker identified in different genetic backgrounds.
. Selection of parents was the first step in present investigation. A PFSR resistant line JCY3-7-1-2-1-b-1 identified as resistant to PFSR caused by M.phaseolina at New Delhi and Ludhiana conditions was selected as resistant parent. This inbred was screened at Hyderabad during kharif, 2011 under artificial inoculation with M.phaseolina culture. It expressed a disease score of 1 under Hyderabad conditions.
In order to study the genetics of resistance to post flowering stalk rot resistant maize inbred JCY3-7-1-2-1-b-1(resistant) and an inbred 5238 (Susceptible) were crossed to produce F1. F1s were selfed as well as back crossed to the susceptible parent to derive F2 and BC1F1 populations, respectively. Parents (P1 and P2), F1 and individuals in two mapping populations F2 (295) and BC1F1 (113) were artificially inoculated with the tooth pick dipped in M. phaseolina culture. F1s inoculated with the culture showed resistant reaction revealing resistance for post flowering stalk rot is governed by dominant gene. F2 population (295 individuals) segregated in 3:1 ratio i.e 214 resistant: 81 susceptible and BC1F1 population (113 individuals) segregated in the ratio of 1:1 i.e. 62 resistant: 51 susceptible confirming that resistance to post flowering stalk rot is governed by a single dominant gene
For mapping of gene resistant to PFSR, a total of 413 microsatellite markers distributed over entire genome (10 chromosomes) were used to screen the parents. Of these, 84 SSR markers from ten chromosomes were found polymorphic in the parents. These eighty four markers were used to screen the bulk DNAs prepared from eight resistant plants and eight susceptible plants from F2 mapping population to find the markers linked to the resistance gene. The markers umc1269 and bnlg439 clearly distinguished resistant and susceptible bulks. Three additional markers umc2012, umc1977 and umc1071 present around umc1269 and bnlg439 were used for screening 295 F2 individual plants. Linkage analysis was carried with the marker data of umc1269, umc2012, umc1977, umc1071 and bnlg439. Linkage analysis revealed that umc1269, umc2012 and umc1977 were linked at a distance of 1.1 cM and 23cM. Single marker analysis was performed for umc1269, umc2012 and umc1977. Results of single marker analysis showed that umc1269 explained 61% (P < 0.0001) of the phenotypic variance of post flowering stalk rot resistance, which again confirms the hypothesis of single-gene inheritance of post flowering stalk rot resistance. umc1269 is the EST SSR of CSU454 gene (Glutathione S-transferase) which is already reported as the resistance governing gene. The marker umc1269 was validated for its association with disease resistance among eight resistant and three susceptible genotypes of maize. The primer umc1269 was able to distinguish the resistant and susceptible genotypes.
From the above investigation this marker umc1269 which was found linked to the gene for PFSR resistance can safely be utilized in future molecular breeding programmes aimed at breeding resistant variety for post flowering stalk rot caused by M.phaseolina.
 
Date 2017-01-03T10:36:45Z
2017-01-03T10:36:45Z
2016
 
Type Thesis
 
Identifier http://krishikosh.egranth.ac.in/handle/1/94078
 
Language en
 
Relation D10012;
 
Format application/pdf
 
Publisher PROFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY RAJENDRANAGAR, HYDERABAD