ANURADHA, GSUNEETHA, P2016-08-102016-08-102010http://krishikosh.egranth.ac.in/handle/1/71968Maize is one of the most important economic cereal crops and an ideal forage crop. It occupies a prominent position in global agriculture. 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.The productivity of maize is influenced by both biotic and abiotic factors. Maize suffers from about 110 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. Stalk rots take a heavy toll, among which stalk rots caused by Macrophomina phaseolina (Tassi) Goid and Fusarium moniliformae results in 30-40% losses. Post flowering stalk rot (PFSR) is the complex disease caused by three fungi,viz., Cephalosporium acremonium, Macrophomina phaseolina, Fusarium moniliformae and one bacterium Erwinia carotovora var zeae. Out of these, post flowering stalk rot caused by Macrophomina phaseolina is the important disease of maize in the state of Andhra Pradesh. Author : P.SUNEETHA Title of the thesis : “TAGGING OF GENE FOR RESISTANCE TO POST FLOWERING STALK ROT IN MAIZE(Zea mays) CAUSED BY Macrophomina phaseolina” Degree to which it is submitted : MASTER OF SCIENCE IN AGRICULTURE Faculty : AGRICULTURE Department : AGRICULTURAL BIOTECHNOLOGY Major Advisor : Dr. G.ANURADHA Principal Scientist (Breeding) Biotechnology Unit Agricultural Research Institute Rajendranagar, Hyderabad – 30. University : ACHARYA N. G. RANGA AGRICULTURAL UNIVERSITY Year of submission : 2010 In order to tag the post flowering stalk rot resistant gene maize inbred lines BPPTI-34 (resistant) and BPPTI -66(Susceptible), were crossed to produce F1. F1’s were selfed as well as back crossed to the susceptible parent to derive F2 and BC1F1 populations respectively. Parents P1 and P2, F1 and two mapping populations F2 and BC1F1 were artificially inoculated with the Macrophomina phaseolina culture. F1s inoculated with the culture showed resistant reaction revealing for that resistance for post flowering stalk rot is governed by dominant gene. F2 population segregated in 3:1 ratio i.e 87 resistant: 27 susceptible and BC1F1 population segregated in the ratio of 1:1 i.e 26 resistant: 24 susceptible showing that resistance to post flowering stalk rot is governed by single dominant gene. A total of 150 microsatellite markers distributed on entire genome were used to screen the parents. Of these, 54 SSR markers from ten chromosomes were found polymorphic in the parents. These fifty four markers were used to screen the bulk DNAs prepared from 10 plants each of resistant and susceptible plants from F2 and BC1F1 populations to find the markers linked to the resistance gene. By bulked segregant analysis (BSA) the marker umc 1269 clearly distinguished resistant and susceptible bulks as that of resistant and susceptible parents indicating that this marker is tightly linked to the gene for resistance to post flowering stalk rot.enTAGGING, GENE,RESISTANCE, POST, FLOWERING ,STALK, ROT, MAIZE, CAUSED, Macrophomina, phaseolinaThesis