Heterosis in sweet sorghum

Abstract

The objective of this work was to evaluate the potential per se of male-sterile and fertility-restorer lines of sweet sorghum (Sorghum bicolor), as well as to detail the heterosis manifested for some traits directly or indirectly related to ethanol production, accumulation rate, and predictability. Evaluations were performed for 20 genotypes, of which 4 are fertility-restorer lines (R), 3 are male-sterile lines (A), and 12 are experimental hybrids (H) resulting from the partial diallel cross between lines A and R, besides a commercial hybrid CV198 used as a check, in four harvest seasons. The experiments were carried out in the municipalities of Lavras and Sete Lagoas, in the state of Minas Gerais, Brazil. The measured traits were plant height, green mass production, juice extraction, total soluble solids content, and megagrams of Brix per hectare. The male-sterile A1 and the fertility-restorer R1 and R3 lines show the best potential per se, considering all traits and their accumulation rate and predictability over harvest times. Heterosis is significant for all traits. The H11, H13, H14, H21, H22, and H33 hybrids are promising because of their better performance per se and higher heterosis.

Inheritance of the main quantitative traits in sweet sorghum hybrids F1

“…In the current study heterosis in productivity of green mass was caused by a simultaneous increase of plant height, stem diameter and plant foliage. This has been confirmed by the study of G. M. R. Lombardi et al [18].…”

Combining Ability of Biomass Sorghum Lines for Agroindustrial Characters and Multitrait Selection of Photosensitive Hybrids for Energy Cogeneration

“…Thus, the heterosis observed in the analysis considering the parents and the hybrids in the present study is due to the epistatic effects and not to the effects of dominance, as expected. Lombardi et al (2018), Rocha (2016), and Durães (2014) in diallel studies on sorghum using the Griffing (1956) model, analyzing parents and F 1 s, also observed high phenotypic variance due to the effects of SCA for plant height and production of fresh biomass and verified the presence of nonadditive gene effects in the determination of these variables but treated them as due to the effects of dominance. Jiang et al (2017,) in more detailed studies of genetics in wheat, showed the importance of epistasis, mainly additive ´ additive in the heterosis calculation, in which it represented 50% of the genetic variation of heterosis, whereas the effects of dominance represented only 16% of the total variation.…”

Heterosis and Inbreeding Depression in Grain Sorghum Hybrids

“…In addition, it indicates that the average of the parentals for plant height is low and that the best of the parentals also has a small height. Lombardi et al (2018) and Singh & Shrotria (2008) reported heterosis and heterobeltiosis positive for plant height, with results of 3% to 52% heterosis for hybrids. The behavior of H% and Hb% of hybrids for plant height converge between works, indicating that, even in selecting shorter parentals, the heterotic gains must be considered to predict an increase in hybrids' height.…”