Comparison between different selection indices in energy cane breeding

Abstract

ABSTRACT. Sugarcane breeding programs have been adapting to a new market demand: aside from high sucrose yield per hectare, the sector needs new cultivars with higher fiber percentages. The selection of sugarcane clones based on phenotype alone is a complex task. The selected clones should display high performance in a series of yieldand quality-related traits. Selection indices can provide information about which clones can best combine the traits of agronomic interest. In this study, different selection indices were evaluated in a population of 220 clones. The following traits were evaluated: weight of 10 stalks with straw, weight of 10 stalks with no straw, tons of cane per hectare with straw, tons of cane per hectare with no straw, sucrose content, fiber percentage, and tons of fiber per hectare. The selection indices of Smith (1936) and Hazel (1943) and Mulamba and Mock (1978), the base index (Williams, 1962), and the index of Pesek and Baker (1969) were used. The selection index of Mulamba and Mock (1978) without economic weight estimates, the index of Mulamba and Mock with economic weights based on heritability, and the index of Pesek and Baker (1969) with the desired gains based on genetic standard deviations were efficient for the selection of energy cane clones with good fiber yield, sucrose content, and tons of cane per hectare.

Realized genetic gains via recurrent selection in a tropical maize haploid inducer population and optimizing simultaneous selection for the next breeding cycles

“…In literature, it has been described that the Pešek and Baker index, when defined in terms of the genetic covariances among traits and the desired gain based on genetic standard deviations, outperformed other methods. It was not the case in the present study but was in others such as the Smith-Hazel selecting energy cane clones with good fiber, sucrose, and cane yield in tons per hectare (de Azeredo et al 2017) or the independent Culling for protein content among families with above-average oil concentration levels (Openshaw and Hadley 1984). The lack of consistency in the PB across different studies is probably due to defining the desired genetic gains and matching them with the genetic variability available in the population and the constraints generated by the genetic correlations among the target traits.…”

Production and Selection of Quality Protein Popcorn Hybrids Using a Novel Ranking System and Combining Ability Estimates

“…Selection indices are more commonly used to select inbred lines in recurrent breeding rather than ranking at the intermediate stage of hybrid selection (Hallauer and Eberhart, 1970;Johnson et al, 1988;Tardin et al, 2007;Marinho et al, 2014). This type of index requires heritability estimates coupled to repeatability to better gauge the genetic value of an inbred (Amaral Júnior et al, 2010;Lima et al, 2012;Marinho et al, 2014;De Azeredo et al, 2017;Da Luz et al, 2018). To further select the best QPP hybrids from the 44 continued crosses, a model was devised to prescreen and comparatively rank hybrids according to suggested genetic potential.…”

Research Article RESEARCH-ARTILE Agricultural performance and genetic parameters for yield-related traits of sugar- and energy cane families derived from planned crosses.

“…This has been the strategy to increase biomass in breeding programs in several countries, e.g., in Puerto Rico (Alexander, 1985), the United States (Giamalva et al, 1985;Eggleston et al, 2007), Barbados (Rao et al, 2007), and Mauritius (Ramdoyal and Badaloo, 2007). In Brazil, studies on energy cane are more recent (Matsuoka et al, 2014;Carvalho-Netto et al, 2014;Silveira et al, 2015aSilveira et al, ,b, 2016Ramos et al, 2017;de Azeredo et al, 2017). Table 3.…”

“…To increase the fiber content of future cultivars, some researchers propose the exploitation of crosses between accessions of these species with sugarcane cultivars with high yields, aiming at the selection of clones with high biomass production and higher fiber contents, called energy cane (Ming et al, 2006;Wang et al, 2008;Silveira et al, 2015aSilveira et al, ,b, 2016Ramos et al, 2017;de Azeredo et al, 2017).…”