Submitted to: Agronomy Society of America, Crop Science Society of America, Soil Science Society of America Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 7/8/2005
Publication Date: 7/20/2005
Citation: Tew, T.L., Pan, Y. 2005. Non-Cytoplasmic Phenotypic Differences in Progeny of a Reciprocal Cross in Sugarcane [abstract]. Agronomy Society of America, Crop Science Society of America, Soil Science Society of America International Annual Meetings. Available: http://crops.confex.com/crops/2005am/techprogram/P5443.HTM
Technical Abstract: A reciprocal cross was made between two commercial sugarcane (Saccharum spp.) cultivars ‘LCP 85-384’ and ‘TucCP 77-42’. Both cultivars have CP 52-68 as their maternal grandparent in their pedigrees; therefore, they are assumed to have the same cytoplasm. In both the plant-cane and stubble crops in Selection Stage II (single-row 2m plots), differences in leaf (erectness, width) and stalk (diameter, height, width) profiles were visually apparent between the progeny of LCP 85-384 x TucCP 77-42 and those of TucCP 77-42 x LCP 85-384. Microsatellite DNA marker analysis confirmed the involvement of both parents in the progeny that were morphologically evaluated. Apparent leaf and stalk profile differences were initially observed between the two sets of progeny in Stage I (seedling stage, 0.4m centers); hence, all progeny were advanced to Stage II where the two sets were randomly inter-planted. In Stage II, two breeders phenotypically examined the progeny and correctly discerned the direction of their maternal/paternal parentage at 75% accuracy (> 50%: p > 0.995). Objective measures of leaf and stalk traits, sucrose content, and estimated cane tonnage confirmed that significant differences existed between the two sets of progeny for several traits. Four times as many progeny of TucCP 77-42 x LCP 85-384 would have been advanced to Selection Stage III as progeny of LCP 85-384 x TucCP 77-42 as a consequence of the two sets of progeny being inter-planted. While the genetic basis for reciprocal differences in this cross remains unknown, the substantiated occurrence of the phenomenon may have important implications for sugarcane breeding programs.