Gujarat Agricultural University, Anand, Gujarat
*Part of the Ph.D. thesis submitted by the senior author to the Gujarat Agricultural University, Sardar Krishinagar.
To investigate the genetics of agronomical as well as anatomical traits in relation to drought resistance of tobacco (Nicotiana tabacum L.), four populations were studied. Each population comprised drought resistant and susceptible parents, their F1, F2 and back cross generations involving either parent. The study was conducted during 1974–75 under rainfed conditions. The different gene effects were estimated . Additive as well as nonadditive effects with the preponderancy of the latter influenced the agronomical (days to flower, plant height, number of curable leaves, leaf area and cured leaf yield) as well as anatomical traits (number of stomata, number of epidermal cells, guard cell length and stomal width). Differences for guard cell width and stomal length were not significant. Cyclic method of breeding involving selection of desired recombinants and their inter se crossing would be more desirable for evolving tobacco cultivars suitable for rainfed areas. Care should be exercised to keep adequate population during the process of breeding.
Negative heterosis values were observed for days to flower, plant stature, number of stomata and number of epidermal cells. Their implications in selecting genotypes resistant to drought are discussed.
