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The composition of seed storage proteins determines the suitability of bread wheat cultivar for different end-use products. high-molecular-weight glutenin subunits are the major determinants of the processing quality of bread wheat flour. The spontaneous translocation of the 1RS arm of Secale cerealeL. in bread wheat is associated with higher grain yield and abiotic stress tolerance, but it leads to deterioration in the end-use quality due to the presence of rye storage secalin protein encoded by Sec-1locus. The 1RSWR.1BL recombinant line W1635 without Sec-1,over-expressed Glu1-Bx7 (Bx7OE) and two stripe rust resistance genes Yr5and Yr17were used as the donor for marker-assisted breeding in the bread wheat cultivars UP2338 and HS240 with 1RS.1BL translocation. A strong positive correlation was found between the micro-SDS sedimentation test (MST) values and Bx7OEin the derivatives along with Glu-D1(5 + 10) indicating the efficacy of Bx7OEin improving the end-use quality. In addition to this, the introgression of Yr5and Yr17genes led to stripe rust resistance in the derivatives for their stable and environment friendly production.

Powdery mildew is a serious fungal disease of wheat caused by Blumeria graminisf. sp. tritici. Chromosome 5U of Aegilops triuncialiscarrying powdery mildew resistance was induced to recombine with chromosome 5A of wheat using ph1bdeletion line. The resulting recombinant progeny lines were tested for resistance and screened with molecular markers. Among 367 progeny lines 8 were immune to powdery mildew, 53 were moderately resistant, 231 moderately susceptible and 75 highly susceptible. Screening of 5U/5A recombinant lines with 5A specific SSR markers indicated that a major powdery mildew resistance gene from A. triuncialiswas introgressed on the long arm of wheat chromosome 5A, along with two other loci, one located in the terminal end of the same arm and the other on the short arm of 5A. Meiotic metaphase-I pairing indicated that chromosome pairing in the resistant recombinant lines was regular with 21 bivalents and high seed set. The DNA markers associated with the introgressions can be used in marker assisted selection for improved powdery mildew resistance in wheat.

Bread wheat sustains genes for grain softness on “Ha” locus of short arm of 5D chromosome. Pina-D1 and Pinb-D1 alleles of “Ha” locus together are responsible for soft grain texture of wheat. The wheat cultivar WL711 had wild type Pinb-D1a and mutated Pinaallele, imparting hard kernel texture. A 5U-5A substitution line of Aegilops triuncialishad extra soft grains. Efforts were made to transfer puroindolines from Aegilops triuncialis5U as 5U-5A substitution line BTC17 to its homeologous chromosome 5A of bread wheat. A total of 367 5U-5A substitution recombinants developed through induced homeologous pairing by ph1bdeletion of Ph1locus were screened for the presence of Pinaand Pinb. Only 23 lines were found to have both Pinaand Pinb.Grain hardness index of recombinants with functional puroindolines was reduced from 6 to 67%. Deletion mapping of wheat 5A chromosome specific SSR markers revealed the maintenance of synteny in 5U and 5A homeologous chromosomes and puroindolines were found to be translocated at the telomeric end of 5A short arm. Translocation of puroindolines from 5U was confirmed by sequencing of Pinaand Pinbgenes. The Pinanucleotide sequence was found 100% similar to Aegilops markgrafii(CC).Puroindoline proteins extracted from the selected softer lines exhibited significant antimicrobial activity against gram positive and gram negative bacteria. Chromosome 5U puroindolines transferred to 5A may be pyramided with 5D of soft wheat to develop extra soft varieties for superior biscuit making quality.

The wheat–rye 1RS.1BL translocation has been extensively utilized in wheat breeding programs across the world for multiple disease resistances, abiotic stress tolerance and higher grain yield. The Sec-1locus present on the 1RS and codes for rye storage protein secalin which causes stickiness in the dough leading to poor bread quality. In addition to this, the absence of Glu-B3/Gli-B1on 1BS in this translocation further deteriorates the bread-making quality of wheat. In the present study, Pavon MA1 was used as the donor parent, and two elite wheat cultivars HS240 and UP2338, having 1RS.1BL translocation, were used as the recipient parents. Pavon MA1 has 1RSWW.1BL translocation in which the Sec-1locus is absent whereas Glu-B3/Gli-B1is present. This 1RSWW.1BL translocation was introgressed in the two wheat cultivars using marker-assisted backcross breeding, and BC2F5derivatives were developed for both the cultivars. The dough quality of these derivatives was analyzed through the micro-SDS-sedimentation test (MST), high-molecular-weight glutenin subunits (HMWGS), loaf volume and micro-dough laboratory test. The dough analysis showed that the elimination of secalin in the derivatives led to the higher loaf volume, dough development time, dough stability and water absorption thus improving its bread-making quality.

The accumulation of total phenylpropanoids and the real time expression of PALgenes in Ocimum tenuiflorumsuspension cell cultures were investigated. A comprehensive analysis of the effects of various abiotic elicitors like jasmonic acid (JA), methyl jasmonate (MeJA), salicylic acid (SA) and precursor feeder L-phenylalanine (L-phe) was done in O. tenuiflorumsuspension cell cultures during elicitation. Ultra performance liquid chromatography based metabolite profiling revealed differential accumulation of three pharmaceutically important phenylpropanoids: caffeic acid, vanillin and ferulic acid. This accumulation corroborated well with real time expression of PALgenes. Biomass analysis during elicitation showed L-phe and JA moderately and MeJA and SA marginally affected the cell growth. Single and repetitive feeding with L-phe induced 22.5 fold accumulations in caffeic acid, ferulic acid and vanillin on day 16 with PALexpression increasing by 9.8–12 fold. SA (1.5 mM) induced 61 fold increase in caffeic acid accumulation with PALexpressions raised by 4.5 fold. MeJA at 25 µM promoted ferulic acid production up to 62 fold having PALexpression raised by seven fold on day 16 of elicitor treatment. Enhanced accumulation of total phenylpropanoids and elevated expression of PALgene were observed during the course of treatment with elicitors and precursor feeder. This stipulates that PALmay modulate the biosynthesis of phenylpropanoids especially vanillin, caffeic acid and ferulic acid. The present study is of particular significance for using suspension cell culture systems of O. tenuiflorum, a less explored plant, for biotechnological production of pharmaceutically important plant secondary metabolites.

A rapid and efficient Agrobacterium rhizogenesmediated transformation system for Ocimum tenuiflorumL., a traditional Indian medicinal plant that occurs in red and green forma, was developed. The plant is a repertoire of several pharmaceutically and nutraceutically important metabolites. Three different types of explants i.e. leaves, hypocotyls and excised shoots, obtained from shoot cultures of in vitrogerminated red and green forma plants were transformed using Agrobacterium rhizogenesstrain ATCC 15834. The transformation efficiency was equal between similar explants of both forma. Transformation efficiency was best in leaves of 4 days while excised shoots and hypocotyls had 6 and 8 days respectively. Transformation frequency of green forma leaves was the highest (70.6%) among all explants. Excised shoots of green forma plants exhibited better transformation (58.3%) than the red forma excised shoots (42.59%). Red forma hypocotyl explants displayed marginally better (26.27%) transformation frequency than green hypocotyl explants (21.14%). Transformation with hairy root was confirmed by the presence of rolC gene through PCR amplification and Southern hybridization. The development of hairy root-based transgenic system for O. tenuiflorumwill pave the way for in vitroproduction of important secondary metabolites.