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Corn (Zea mays L.) is the third most important staple cereal crop after wheat and rice, which is used for human consumption, biofuels, livestock feed and also as raw material in industry. It provides over 20% of total calories in human diet. The sh2 mutant in supersweet corn composites and hybrids leads to enhanced sugar and vitamin B3 content in developing grains and reduction of starch content in mature grains. The deficiency of essential amino acids lysine and tryptophan in maize proteins has been significantly improved with the use of opaque2 (o2) allele leading to the development of quality protein maize (QPM). In this study, the opaque2 allele was pyramided in a sweet corn composite with Shrunken 2 (sh2) allele to develop a sweet and quality protein maize composite with higher content of essential amino acids and vitamins. QPM inbred line VQL-2 was used as the donor parent for o2 allele having higher value of lysine (3.64 ± 0.1 g/100 g), tryptophan (1.91 ± 0.01 g/100 g) and vitamin B3 (1.97 ± 0.02 mg/100 g) and the Punjab sweetcorn-1 as the recurrent parent having higher values of vitamin B1 (0.1 ± 0.01 mg/100 g) and C (6.58 ± 0.82 mg/100 g). The EU-Sweetcorn QP composite was developed through marker-assisted backcross breeding using umc1066 marker linked to o2 mutant and selection of homozygous sh2sh2 plants was done phenotypically at maturity. The EU-Sweetcorn QP composite developed for the first time in India has superior nutritional quality, e.g., high essential amino acids lysine and tryptophan and vitamins B1, B3 and C as estimated using RP-HPLC–PDA. [ABSTRACT FROM AUTHOR]

Zinc is essential for growth and development of all living organisms, especially human being. Deficiency of micronutrients like zinc and iron has been linked to the manifestation of hidden hunger. Therefore, it is imperative that development of some rapid screening method for bioavailable zinc in various crops and food commodities would be an essential addition in battle against zinc deficiency related hidden hunger. One such method could be the usage of fluorescence based zinc ion sensing probe which would be robust and convenient for estimating bioavailable zinc. To address this issue, NBD-TPEA, a highly sensitive zinc ion sensing probe, have been used in this study towards the development of a novel fluorescence based approach for the analysis of zinc bioavailability in Caco-2 cells as an in-vitro cellular model. The use of this probe showed dose dependent sensitivity towards increasing concentrations of zinc ion uptake by Caco-2 cells. It also showed specificity for zinc ion uptake as compared to other metal ions in-vitro. These observations correlated extremely well with zinc uptake analysis by cell imaging and conventional analytical technique like, ICP-MS. The developed assay was then tested in mushroom and some selected biofortified derivatives of wheat for determining the levels of their bioavailable zinc using Caco-2 cells. The data as obtained with these food samples in our developed bioassay correlated well with the other sophisticated analytical techniques thus validating our cell based assay. Hence, the developed assay could serve as a simple but sensitive tool for determining bioavailable zinc in various food samples. [ABSTRACT FROM AUTHOR]

In agricultural crops, seed growth is important for high grain yield. Starch contributes about 50–80 % of the dry weight of seed, and its quality affects both processing and nutrition quality. Despite the wider importance of starch metabolism, the genes involved have not been given much attention or exploited for their use in molecular breeding. Therefore, it is of great interest to analyze the expression of genes involved in starch metabolism for improvement of starch-related traits through molecular breeding. In this study, a quantitative gene expression analysis of 25 starch metabolism genes was conducted in three bread wheat (Triticum aestivum) genotypes differing in yield- and starch-related traits at five seed developmental stages, i.e., 7, 14, 21, 28, and 35 days after anthesis. Their sequences were physically mapped to chromosomes using the wheat genome sequence data through in silico analysis. Their expression data showed dynamic variation during seed development in wheat genotypes. The 25 genes were divided into four groups depending on their expression patterns during seed development. For example, one group was characterized by a high level of expression at early and middle stages as exhibited by different isoforms of starch synthases, starch-branching enzymes, isoamylase, and transcription factors (TaRSR1 and SPA). The enzymes of these genes are key factors in starch biosynthesis. The starch metabolism genes with high expression levels will be sequenced in a wheat germplasm set to develop single nucleotide polymorphism markers for improvement of yield- and starch-related traits through molecular breeding approaches. [ABSTRACT FROM AUTHOR]

Triticum monococcum, the diploid A genome species, harbours enormous variability for resistance to biotic stresses. A spring type T. monococcum acc. 14087 was found to be resistant to Heterodera avenae (cereal cyst nematode, CCN). A recombinant inbred line population (RIL) developed by crossing this accession with a CCN susceptible T. boeoticum acc. 5088 was used for studying the inheritance and map location of the CCN resistance. Based on composite interval mapping two QTL, one each on chromosome 1AS and 2AS, were detected. The QTL on 1A, designated as Qcre.pau- 1A, appeared to be a major gene with 26% contribution to the overall phenotypic variance whereas the QTL on 2A designated as Qcre.pau- 2A contributed 13% to total phenotypic variation. Qcre.pau- 1A is novel, being the only CCN resistance gene mapped in any 'A' genome species and none of the other known genes have been mapped on chromosome 1A. The QTL Qcre.pau- 2A might be allelic to Cre5, a CCN resistance gene transferred from Ae. ventricosa and mapped on 2AS. The Qcre.pau- 1A was transferred to cultivated wheat using T. durum cv. PBW114 as the bridging species. Selected CCN resistant F lines showed introgression for the molecular markers identified to be linked with CCN resistance locus Qcre.pau-1A. Thus, this gene alone could impart complete resistance against CCN. These introgression lines can be used for marker-assisted transfer of Qcre.pau- 1A to elite wheat cultivars. [ABSTRACT FROM AUTHOR]

T-DNA insertional mutagenesis is one of the most important approaches for gene discovery and cloning. A fertile polyembryo mutant generated by T-DNA/ Ds insertion in Oryza sativa, cv. Basmati 370 showed twin or triple seedlings at a frequency of 15–20%. T-DNA insertion was confirmed by 950 bp hpt gene amplification in the promoter region of the candidate gene. The annotated protein corresponding to the OsPE candidate gene has been reported as a hypothetical protein in O. sativa. OsPE gene lacked functional homologs in other species. No OsPE paralog was found in rice. No conserved domains were found in the protein coded by OsPE. RT-PCR showed the expression of OsPE gene in Basmati 370 shoots. Full-length OsPE gene was cloned in Basmati 370. The combined use of Southern blot, genome walking, TAIL-PCR, RT-PCR techniques, and bioinformatics led to the identification of a candidate gene controlling the multiple embryos in rice. There is gain of function, i.e., multiple embryos in the seeds in the knockout mutant OsPE whereas its wild-type allele strictly controls single embryo per seed. The seeds with multiple embryos are distributed at random in the rice mutant panicle. The origin of multiple embryos, whether apomictic, zygotic or both is under investigation. [ABSTRACT FROM AUTHOR]

Biofortification through genetic manipulation is the best approach for improving micronutrient content of the staple food crops to alleviate hidden hunger, namely, the deficiency of Fe and Zn affecting more than two billion people worldwide. An interspecific hybridization was made between T. aestivum line Chinese Spring (CS) and Aegilops kotschyi accession 3790 selected for high grain iron and zinc concentration. The CS × Ae. kotschyi F1 hybrid with low chromosome pairing was highly male and female sterile. This was backcrossed with wheat cultivars to get seed set. The selfed BC1F1 and BC2F1 plants with high grain iron and zinc concentration were selected in subsequent generations. The selected derivatives showed 60–136% enhanced grain iron and zinc concentration and 50–120% increased iron and zinc content per seed as compared to the recipient wheat cultivars. Thirteen cytologically stable, fertile and agronomically superior plants with high grain iron and zinc concentrations were selected for molecular characterization. The application of anchored wheat SSR markers, transferable to Ae. kotschyi, to the high grain iron and zinc containing derivatives indicated introgression of group 2 and group 7 chromosomes of Ae. kotschyi. GISH and FISH analysis of some derivatives confirmed the substitution of chromosomes 2S and 7U for their homoeologues of the A genome, suggesting that some of the genes controlling high grain micronutrient content in the Ae. kotschyi accession are on these chromosomes. [ABSTRACT FROM AUTHOR]