Studies on resistance mechanisms and identification of molecular marker(s) linked to Chilo partellus (Lepidoptera: Pyralidae) resistance in maize
| dc.contributor.advisor | Subhash Chander | |
| dc.contributor.author | ANIL KUMAR CHOLLA | |
| dc.date.accessioned | 2017-11-01T06:11:47Z | |
| dc.date.available | 2017-11-01T06:11:47Z | |
| dc.date.issued | 2016 | |
| dc.description | T-9456 | en_US |
| dc.description.abstract | Maize (Zea mays L.) is an important cereal crop grown in largest number of countries (about 170) covering different agro-climatic conditions. It has the highest production and productivity among the cereals. The area, production and productivity of maize in India is around 9.4 m ha, 24.4 m t and over 2.5 t/ha, respectively (Economic Survey, GOI 2014-15). Yield losses due to Chilo partellus (Swinhoe) range from 26.7 to 80.4% in different agro climatic regions (Panwar, 2005). Thirty diverse maize genotypes were evaluated for ovipositional antixenosis to identify genotypes with high level of resistance to spotted stem borer, C. partellus. In both multi and nochoice tests, oviposition was observed on all genotypes, which significantly differed among the genotypes. Genotypes, WNZPBTL 2, CM-500, PFSR 51016/1, WNZPBTL 6, AEB (Y) C5 F 38-1, HK I-PC-5 and CM-202 recorded significantly lower mean number of egg masses per plant. On the other hand genotypes, HKI-1378, HKI-1352, HK I-PC-5 and HKI-163 had higher mean number of eggs per plant and were on par with each other and close to the susceptible check, Basilocal selection. Principal component analysis (PCA) identified the stem tunnelling (ST, %), dead hearts (DH, %) and leaf injury rating (LIR) as most important traits with regard to genotypic response to stem borer resistance. Correlation studies between multi and no-choice experiments revealed significant positive correlation with egg masses laid on maize genotypes (r=0.36, df=28), and number of eggs laid (r=0.5, df=28). Correlation between morphological traits and damage parameters revealed negative association of seedling vigour with LIR and DH, plant height with LIR, and photosynthetic area (leaf width) with DH. Morphological traits seedling vigour, plant height and photosynthetic area thus can serve as easily visible traits for resistance screening against stem borer. Based on screening, maize genotypes, WNZPBTL 2 and HKI 1352 were selected as resistant and susceptible parents respectively. Individuals of mapping population (F2) developed from WNZPBTL 2 and HKI 1352 were phenotyped for the LIR and classified on 1 to 9 scale. F2 distribution of LIR indicated monogenic control of spotted stem borer resistance in maize with dominance of resistance over susceptibility. Screening of parents with 200 simple sequence repeat (SSR) markers, identified 37 polymorphic markers across the genome. Chromosomes 1, 5 and 6 revealed to carry most distinct genome, whereas chromosome 1 was more similar between parents. Only one marker (bnlg1057) at map location bin1.06 showed polymorphism between parents as well as bulks with distinct frequency of resistant and susceptible alleles. Strength of linkage between marker and trait in F2 was assessed by binary logistic regression, which was significant with regression coefficient of 1.453. Additional twelve markers from bin1.06, flanking bnlg1057 were selected to identify closer marker to the gene of interest but absence of polymorphism between parents suggested use of different population to find closely linked markers. Based on present study it can thus be concluded that screening of 28 inbreds of Indian origin for leaf injury rating (LIR) helped to identify two contrasting resistant and susceptible plants. Complete phenotyping of F2 individuals in present investigation established that C. partellus resistance was under monogenic control with dominance of resistance over susceptibility. One potential simple sequence repeat marker (bnlg 1057) linked with the gene of interest was identified using bulk segregant analysis. | en_US |
| dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/5810034326 | |
| dc.keywords | Studies on resistance mechanisms and identification of molecular marker(s) linked to Chilo partellus (Lepidoptera: Pyralidae) resistance in maize | en_US |
| dc.language.iso | en | en_US |
| dc.publisher | Division of Entomology ICAR-Indian Agricultural Research Institute New Delhi | en_US |
| dc.sub | Entomology | en_US |
| dc.subject | null | en_US |
| dc.theme | Studies on resistance mechanisms and identification of molecular marker(s) linked to Chilo partellus (Lepidoptera: Pyralidae) resistance in maize | en_US |
| dc.these.type | Ph.D | en_US |
| dc.title | Studies on resistance mechanisms and identification of molecular marker(s) linked to Chilo partellus (Lepidoptera: Pyralidae) resistance in maize | en_US |
| dc.type | Thesis | en_US |