A study of diallel crosses between varieties of nicotiana tabacum L. for yield components

Abstract

To predict the behaviour of selections in the F 1 generation itself before taking them to the advanced generations for further screening, the applicability of diallel cross analysis was studied .For this purpose four N. tabacum varieties were crossed in all combinations to constitute a diallel system and data collected on green leaf, saleable leaf i .e . sum of bright leaf and medium leaf yields, number of days taken for flowering, length and breadth of the middle leaves at maturity of the F l plants were subjected to JINKS and HAYMAN method of analysis .The results showed that Delcrest is a good combiner in throwing better recombinations . It always improved the yielding potential of the poorer parent . In the light of the graphical analysis, the results were discussed in relation to the improvement of the crop and predictions made as to which cross throws better strains . The characters studied are mostly additive in gene action . The scope of this method in the breeding projects to evolve superior strains was outlined .

Study of inheritance of some agronomic and morphological traits in burley tobacco by graphic analysis of diallel cross

“…Some previous investigations of the inheritance of major tobacco traits (yield, plant height, leaf number, days to flowering, leaf length and width) using graphic analysis show contradictory results. Starting from yield, a major tobacco trait, according to the studies made so far overdominant inheritance was estimated by graphic analysis (Jung et al 1982, Šmalcelj 1983, Butorac et al 1999), but partial dominance was also found (Gopinath et al 1966, Shamsuddin et al 1980, Pandeya et al 1983). In our present investigations, according to the graphic analysis, yield was inherited overdominantly in both years of investigation.…”

“…Different results were obtained depending on the investigated traits, and also on the genetic materials as well as the leaf position on the stalk. In most studies additive variance in the inheritance of leaf width was estimated (Gopinath et al 1966, Espino and Gil 1980, Ibrahim and Avravtovscukova 1982. According to our results, leaf width was inherited overdominantly in one year and partly dominantly in the other year.…”

“…No interallelic interaction was present, which is in agreement with our present results. Gopinath et al (1966) and Pandeya et al (1983) studied the inheritance of leaf length using the graphic method. According to their results, this trait is inherited partly dominantly and there is no interallelic interaction.…”

“…In most papers, independently of tobacco type, additive variance in inheritance of leaf number (Shamsuddin et al 1980, Šmalcelj 1983, Shoai Daylami and Honarneja 1996 and leaf width was estimated (Gopinath et al1966, Espino and Gil 1980, Ibrahim and Avravtovscukova 1982. The graphic method indicates overdominant inheritance of yield (Jung et al 1982, Šmalcelj 1983, Butorac et al 1999, and also the participation of partial dominance (Gopinath et al 1966, Shamsuddin et al 1980, Pandeya et al 1983). Leaf length is also inherited overdominantly (Ibrahim andAvravtovscukova 1982, Butorac 1997) and partially dominantly (Gopinath et al 1966, Pandeya et al 1983.…”

“…The graphic method indicates overdominant inheritance of yield (Jung et al 1982, Šmalcelj 1983, Butorac et al 1999, and also the participation of partial dominance (Gopinath et al 1966, Shamsuddin et al 1980, Pandeya et al 1983). Leaf length is also inherited overdominantly (Ibrahim andAvravtovscukova 1982, Butorac 1997) and partially dominantly (Gopinath et al 1966, Pandeya et al 1983. Ukai (1991) investigated the influences of environmental variations involved in the values of a diallel table on the (Wr Vr) graph.…”