Browsing by Author "Zhao, L"

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Field assessment and further development of high-sucrose sugarcane: final report 2014/069
(Sugar Research Australia Limited, 2017) Wu, L; Lakshmanan, P; Zhao, L
Sucrose accumulation is critically important in determining sugarcane productivity. Yet, improvement in sucrose content in sugarcane has been almost stagnant for decades in many sugarcane growing countries, including Australia. This project has made significant improvement in sucrose content in sugarcane varieties by manipulating the activity of a specific gene involved in sucrose metabolism. In a previous study, we created transgenic sugarcane clones with Q117 background, which showed 15-25% improvement in sucrose content under glasshouse conditions. This high-sucrose phenotype was reproduced in the field in this project. The same transgenic technology was successfully applied to Q208A and Q240A and improvement of one to two units in CCS were recorded for seven lines, out of 365 tested, under field conditions. The high-sucrose phenotype was stable across plant and first ratoon crop during the two-year field study. Despite of the increase in sugar content, three lines showed comparable cane yield and fibre content to that of untransformed controls. Molecular analyses of high-sucrose lines confirmed that the phenotype was caused by RNAi-mediated down-regulation of target gene expression. The study demonstrates the potential of targeted gene manipulation for sucrose improvement in already established sugarcane varieties. Considering the growing resistance to genetically modified food crops, use of alternative emerging technologies such as gene editing may be the way forward for realising the same or better results.
Seed-based in vitro propagation to accelerate variety development : ASSCT peer-reviewed paper
(ASSCT, 2021) Zhao, L; Bolton, C; Piperidis, G; Eglinton, J
To shorten the current lengthy selection process in sugarcane breeding and to accelerate genetic gain, Sugar Research Australia is implementing a range of novel breeding strategies and selection tactics. One strategy is to rapidly evaluate the progeny of elite crosses in replicated trials without passing through the traditional Stage 1 trials. However, insufficient planting material hinders its adoption. A seed-based in vitro propagation system has been developed for sugarcane in which sodium hypochlorite (bleach) and plant preservative mixture (PPMTM) were used in the sterilisation of seeds and seedlings, as well as in the treatment of infected seedlings. The system had been successfully implemented to propagate over 1000 clones of the elite cross Q208A x CP74-2005, for a Stage 2 selection trial. The new system, a first for sugarcane, is more cost efficient, providing three times the number of clones as in the seedling-based micropropagation system with the same input of resources. This innovation will shorten the selection cycle of proven elite crosses by up to 3 years, accelerating the delivery of new varieties.