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Not AvailablePhytic acid (PA) is one of the important anti-nutritional factors which affect the bioavailability of micronutrients like iron, zinc. Maize being one of the important food and feed crop requires serious attentions to reduce its PA; majority of total phosphorous is stored in this form which makes it unavailable to monogastric animals. The phosphorus thus stored in the form of PA phosphate contributes to water pollution because it is excreted as such. PA being strong chelating agent also forms phytate salts with cation mineral elements like iron, zinc, calcium etc., thus affects the bioavailability of micronutrient mineral elements. Thus causes micronutrient mineral deficiency in humans and phosphorous deficiency in animals. In the present study efforts have been made to introgress gene (lpa2) determining lowPA has been transferred from low-phytate mutant line lpa2 into an elite inbreds LM14 and LM17 through marker-assisted backcross breeding (MABB). The BC2F2 near-isogenic lines (NILs) have been developed through introgression of lpa2 gene. Out of 118 BC2F2 plants of LM 17 × LPA2 family, 26 were homozygous positive for lpa2 gene and 65 were heterozygous; the remaining plant were negative (27 plants). Similarly, in LM 19 × LPA2 cross, out of 127 BC2F2 plants 24 were homozygous for lpa2and 70 plants were heterozygous. The remaining plants were (33) were negative for the lpa2 gene. The molecular marker, umc2230 was used as linked marker to select lpa2 gene. Whereas the sequence-tagged molecular markers (STMS), were chosen to select segregants with the highest genome recovery. The recurrent parent genome (RPG) varies between 79-89 and 82-93 per cent in BC2F2 individuals derived from LM 17 × LPA2 and LM 19 × LPA2 respectively. The agronomic performance of selected NILs of BC2F3 and the respective recurrent parents has shown that the NILs are comparable with respective recurrent parents for days to flowering and almost all the yield component traits like number of ear length, ear girth, kernel rows, kernels per row, test weight etc. and also biochemical analysis for lowPA is underway. The NILs developed would be used to reconstitute the original hybrids.Not Availabl

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Not AvailableMaize (Zea mays L.) is grown on nearly 190 million ha in about 165 countries with total production yielding approximately 39% of total grain production. In India maize is third most important cereal crop after rice and wheat and accounts for around 10% of total food grain production. Maize contributes 25 to 35 per cent of total calories of the diets in several African, Asian and Latin American countries. Thus it is a valuable source of food and feed worldwide. Further enhancement of nutritional value through micronutrients like provitamin A in maize through biofortification could play an vital role in reducing the micronutrient malnutrition, the major challenge to ensure nutritional security in developing countries. Biofortification is the process by which the nutrient density of food crops is increased through conventional plant breeding and/or improved agronomic practices and/or modern biotechnology without sacrificing any characteristic that is preferred by consumers or most importantly to farmers. In the present study, gene encoding β-carotene hydroxylase 1 (crtRB1) alleles associated with higher β-carotene concentrations was introgressed into elite inbred line LM 17 and 19 using marker-assisted backcross breeding (MABB). The donor for crtRB1 gene was CIMMYT5 inbred line. For foreground selection crtRB1 gene-based simple sequence repeat (SSR) markers were successfully used in foreground selection. Presently introgressed lines are in BC2F2 generation. In LM17 × CIMMYT5 cross, out of 90 plants, 31 plants were homozygous, 42 plants were heterozygous while 17 plants were negative and in LM19 × CIMMYT5 cross out of 167 plants, 54 plants were homozygous, 87 plants were heterozygous while 26 plants were negative. The plants carrying gene of interest, were screened with SSR markers and recovery of recurrent parent genome (RPG) in background selection ranged between 82.40 - 93.70% for the LM17 × CIMMYT5 and 84.7091.30% for LM19 × CIMMYT5. The newly developed provitamin A near siogenic lines (NILs) developed in both the crosses are comparable with their recurrent parents for agronomic performance for different traits like days of anthesis, ear diameter, ear height, ear length, kernels per row and kernels rows, however the biochemical analysis is being carried out.Not Availabl

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Not AvailableProtein malnutrition is one of the challenges to ensure nutritional security of the global poor masses especially in rural population of the developing world. Cereals are deficient in some of essential amino acids like lysine and tryptophan. The deficiency leads to one of the protein deficiency disorder like kwashiorkor. Therefore the challenge is to deliver nutritious, safe and affordable food to reduce the impact of nutritional deficiency. Quality protein maize (QPM), contain double the amount of lysine and tryptophan as compared to normal maize is one of the intervention could play vital role to reduce amino acid deficiency. In this context, several efforts have been made to enhance the lysine and tryptophan levels through marker assisted introgression of o2 gene into elite inbred lies of maize. In the present study, opaque2 gene along with phenotypic selection for kernel modification was incorporated using marker assisted backcross breeding (MABB) program into normal inbred line i.e. LM19. This is the parental line of popular single cross hybrids PMH6 in India. HKI 163 was the donor for opaque2 allele. opaque2 genebased simple sequence repeat (SSR) markers were successfully used for introgression of opaque2 allele. BC2F2 population derived from marker identified BC2F1 individuals were subjected to foreground selection. 86 BC2F2 plants derived from LM19 × HKI 163 cross were screened for o2 gene linked molecular marker. The result showed that 50 plants were heterozygous, 18 plants were homozygous while 15 plants were negative for o2 allele. The o2 carrying homozygous plants were subjected to background selection using sequence tagged microsatellites (STMS) to accelerate the recovery of recurrent parent genome (RPG). The background selection has revealed that the RPG varied from 79 87 % in BC2F2 generation derived from LM19 × HKI 163 cross. The newly developed near isogenic lines (NILs) from the hard endosperm kernels were evaluated for desirable agronomic and biochemical traits in replicated trials and the best lines were chosen to represent the QPM version of LM19. The agronomic performance of the selected BC2F2 population for LM19 × HKI 163 inbreds showed comparable performance with LM17 in days of anthesis, days of silking and yield and yield component traits.Not Availabl