Agronomic performance and tensile strength analysis of promising bunchy top virus resistant BC3F1 abaca (Musa textilis Nee.) hybrids

Breeding for abaca bunchy top virus (AbBTV) resistance, acceptable fiber quality and good agronomic traits are important to aid the ailing Philippine abaca industry. Selected BC3F1 (63 clones) hybrids derived from a cross between Pacol (source of AbBTV resistance) and Inosa (recurrent parent for good agronomic and fiber quality) were morphologically characterized and fiber tensile strength was evaluated. Highly significant differences for number of leaves, pseudostem freshweight and total weight of fiber were observed among clones. Preliminary experiment to understand the variation of fiber tensile strength across pseudostem and fiber positions was conducted. Fibers extracted were divided into three leafsheath locations. Each location was divided into three equal fiber positions (base, middle and top) to obtain the fiber samples. Analysis of variance showed significant differences across fiber positions which provide additional information to where fibers should be sampled to increase precision and accuracy of tensile strength measurements. Tensile strength of clones was then measured and analyzed using RCBD with sub-sampling and showed highly significant differences among clones was then measured and analyzed using RCBD with sub-sampling and showed highly significant differences among clones (BC3F1 clones and parents). Using selection index for different economic weights per trait, higher weight coefficient for traits such as total fiber weight per plant (13%), percent fiber recovery (189), mean tensile strength (24%), yield per hectare (15%) and the remaining 30% is distributed to other traits. Four promising BC3F1 clones have been identified (BC3-111-21, BC3-111-26, BC3-146-7 and BC3-146-8) to have long fiber ranging from 176.33 to 189.33 cm, substantial percent fiber recovery (0.50 to 0.91%), high tensile strength (20.57 to 33.66 kg/g/m) and fiber yield ranging from 0.81 to 2.21 tons/ha. These selected clones can be mass propagated, forwarded for multi-environment trials and eventually be released for abaca farmers.