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Major fraction (60%) of seed storage protein in maize is zein which determines the quality of food and feed. Zeins comprise four subfamilies e.g., α , β, γ and δ zeins. Among these, α-zeins are the major prolamin subunits in maize. α-zeins are rich in glutamine, leucine and proline but, deficient in essential amino acids like lysine and tryptophan causing malnutrition. The opaque-2 (o2)-a natural recessive mutation in maize led to nearly double the lysine and tryptophan content in endosperm due to a decrease in the synthesis of zein proteins and increase in the other seed protein bound lysine and tryptophan. RNAi studies proved down regulation of 22kD zeins than the 19kD component as the biochemical basis of QPM phenotype. However, the opaque-2 mutation made the endosperm chalky and soft resulting damaged kernel while harvesting, poor germination, increased susceptibility to pest and diseases, inferior for food processing and in general reduced yield. Later, combining opaque-2 allele with its desirable genetic modifiers made it possible to breed QPM genotypes having hard kernel with high lysine and tryptophan content. Since, opaque-2 is a recessive mutation and endosperm specific, and biochemical analysis of lysine and tryptophan content is expensive; conventional backcross breeding alone is inefficient for the nutritional enrichment of maize. However, use of opaque-2 gene specific markers provided excellent opportunities for conversion of elite normal inbreds to homozygous o2/o2 forms through marker assisted selection (MAS). In India, Vivek QPM-9: a hybrid of two QPM introgression lines is being widely used for commercial cultivation.

Malnutrition continues to be a crucial problem particularly in developing countries. For this, rice breeding needs to be reoriented to improve cooking quality, glycemic load, protein, amino acid, micronutrient, vitamin, phenolic and flavonoid content while increasing the yield potential. Indeed, the task is challenging as most of the traits relating to quality and nutrient status in rice are complex. In this pursuit, the authors reviewed the general background of malnutrition; explore the genetic basis for improvement of nutritional status including quality aspects and possible breeding perspective to mitigate the problem. This would certainly help breeders to develop nutritionally rich rice varieties.

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Somaclonal variation was revealed among regenerants in four genotypes (Nirmal, P24, Nayagarh local and Dhenkanal local) of grasspea (<italic>Lathyrus sativus</italic> L.) following long term in vitro culture of internode explants. Most of the somaclones which survived till maturity had revealed chromosomal abnormalities and variation in one or more morphological and/or agronomic traits. Some of the variant phenotypes especially those relating to developmental variations were not inherited to R2 generation owing to elimination of chromosomal aberrations that preclude normal morphogenesis. Somaclones with variation in flower colour, seed colour, leaflet length and breadth, foliage and pod pigmentation may be used as genetic markers in breeding <italic>Lathyrus sativus</italic>. Besides, variants with broad leaf, dwarf height, long pod, large seed, short duration and synchronous maturity are agronomically desirable. A large seeded somaclone NGOG 5 having high seed yield and low neurotoxin content (ODAP) recovered in this pursuit, can be a desirable candidate for future breeding programme.

Genetic diversity among 20 cashew hybrids and their eight parents were assessed using 15 RAPD primers which resulted 1742 alleles with an average of 62.21alleles per genotype. RAPD profiles revealed 94 polymorphic bands out of total 107 scorable bands resulting 87.85% polymorphism. On an average 7.66 bands were produced with a range of 4-15 amplicons per primer. The maximum number (14) of polymorphic bands (210 to 3250bp) was produced by primer OU-34 with high polymorphic information content (PIC) and resolving power (Rp) values. Cashew hybrids H 6 and D 19 maintained very high level of average genetic dissimilarity with rest of the test genotypes. The above hybrids comprising the most divergent genetic group (Cluster-I) had shown significantly above average productivity and these could enrich the cashew gene pool for further genetic improvement for nut quality and yield per se. Besides, the genotype-specific bands identified in the present study are useful for identification of cashew genotypes.

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