Abstract
The creation of triploid hybrids is an important genetic improvement strategy for the development of new commercial citrus scion varieties. The objective of this work was to quantify the frequency of triploids obtained from natural and controlled crosses of different mandarin varieties under varying environmental conditions in the state of Bahia. The experiments were conducted in the municipalities of Cruz das Almas (Recôncavo Baiano region) and Mucugê (Chapada Diamantina region). The first experiment was based on fruits from open pollinations of the varieties ‘Page’, ‘Ortanique’, ‘Ellendale’, ‘Clemenules’, ‘Swatow’, ‘Piemonte’, ‘Fortune’, ‘South Africa’, ‘Montenegrina’, ‘Kincy’, ‘Span Americana’, ‘Fremont, ‘Nova’, ‘Dancy’ and ‘Murcott’, and the second involved fruits from controlled crosses of female parents ‘Nova’, ‘Fortune’ and ‘Ortanique’ and male parents ‘Page’, ‘Montenegrina’, ‘Swatow’, ‘Fremont’ and ‘Kincy’. The seeds selected were inoculated in test tubes containing approximately 10 mL of Woody Plant Medium (WPM). When the plants reached circa 60 days of age, leaf samples were removed for quantification of the DNA by the flow cytometry technique. In Mucugê, three triploids were identified from open pollinations, ‘Clemenules’ (1) and ‘Ortanique’ (2), while in Cruz das Almas, no triploids were obtained. In the controlled crosses, triploids were only obtained in Mucugê: ‘Ortanique’ × ‘Montenegrina’ (4), ‘Ortanique’ × ‘Kincy’ (1) and ‘Ortanique’ × ‘Swatow’ (2). Based on the data, it is suggested that the environmental conditions of Mucugê favored the formation of triploids.
Highlights
Citrus are among the most important group of fruit trees in Brazil, due to the nutritive value of the fruits and the socioeconomic role they play in the export (Knudsen, Almeida, Langer, Abreu, & Halberg, 2011)
The objective of this study is to quantify the frequency of triploids obtained from natural crosses and controlled crosses of different mandarin varieties in varying environmental conditions in the state of Bahia, in Brazil
Triploid citrus hybrids can be obtained by crossing diploid parents through production of unreduced gametes by the female parent, where the frequency of these gametes depends on the genotype (Esen & Soost, 1971; Luro, Maddy, Jacquemond, Froelicher, Morillon, Rist, & Ollitrault, 2004)
Summary
Citrus are among the most important group of fruit trees in Brazil, due to the nutritive value of the fruits and the socioeconomic role they play in the export (Knudsen, Almeida, Langer, Abreu, & Halberg, 2011). In this aspect, the expansion of the genetic base of Brazilian orchards, especially related to the varieties used for scion and rootstocks, including those with capacity to adapt to abiotic stresses, tends to contribute significantly to the achievement of economically superior incomes in the country (Syvertsen & Sanchez, 2014). Triploid hybrids in citrus can be obtained from crosses of diploid (2×) parents with tetraploids (4×), hexaploids (6×) with tetraploids (4×) and diploids (2×) with diploids (2×) or open pollinated, in the case of 2× with 2×, the triploid embryos originate from the fertilization of non-reduced female jas.ccsenet.org
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
