Location: Floral and Nursery Plants Research
Project Number: 8020-21000-058-000-D
Project Type: In-House Appropriated
Start Date: Jun 26, 2013
End Date: Feb 13, 2018
This project applies biotechnology to effectively mitigate the impact of pests and pathogens on priority floral crops and develops systems that can be manipulated to preserve select hardwood tree taxa for future genetic engineering applications. Genetic engineering of floral crops for pest and pathogen resistance contributes to sustainable production. There has been little research done on migratory nematodes such as Pratylenchus, and this project addresses the use of transgenes that may be effective in controlling Pratylenchus. Viruses are always a problem for propagated plants, particularly flower bulb crops that are propagated from the same bulb for many years. This project determines if an RNAi approach is effective for control of Cucumber mosaic virus (CMV), an economically important virus that affects numerous crops. In vitro manipulation of plants through genetic engineering allows for rapid clonal propagation, ploidy level manipulation, and preservation of germplasm and cryopreservation. Hardwood trees have been difficult to manipulate in vitro, and there are few reports of research done with North American hardwood tree taxa. This project will explore the possibilities of regenerating plants from select oak, elm, or maple taxa for future applications by using either embryogenesis or organogenesis and maintaining plants in vitro by micropropagation. Objective 1: Characterize the interaction between Pratylenchus and transgenic Easter lilies transformed with currently available anti-nematode genes for resistance response. (NP301; C1, PS 1B) Objective 2: Identify genes involved in the metabolic activities of Pratylenchus, using an RNAi approach, and determine if they are effective in enhancing resistance to Pratylenchus, using a soybean hairy root system. (NP301; C1, PS1B) Objective 3: Develop and evaluate lilies containing an antiviral gene for resistance to Cucumber mosaic virus. (NP301; C1, PS 1B) Objective 4: Develop a regeneration system from embryogenic callus for priority hardwood tree species in the tree improvement program at the U.S. National Arboretum. (NP301; C3, PS 3B)
Genetic engineering will be used to introduce genes into Easter lily for nematode and cucumber mosaic virus resistance. Genes that will be tested for nematode resistance are two Bt genes and a cystatin genes. Two genes targeting nematode movement will be used in an RNAi approach against the root lesion nematode. Seeds and cuttings from select hardwood tree species will be cultured in vitro and used for micropropagation and induction of callus. Treatments will be used to determine if plants can be regenerated from the callus.