1. Please state project objectives and what work was done this quarter to address them:
The objectives of this research are
1) to reveal the distribution and stability of NMV-M/CFL in in citrus plants: We have inoculated sweet orange, lemon, grapefruit, pumelo, and Kumquat with NMV-M/CFL, and using graft-based propagated NMV-M-infected plants. The virus is systemic infected all citrus plants with different titers of the virus. However, like HLB bacterium, the virus tended to be unevenly distributed in citrus plants. We also surveyed our existing plot of research field with NMV-M, and revealed the virus was not wide-spread. We have identified better combination of citrus genotypes such as new bud-sport selections of grapefruit and Valencia, which yielded better protection with NMV-M infection.
2) to propagate the NMV-M/CFL-infected scions and rootstocks and evaluate their HLB-prevention and curative potentials in greenhouses and fields: NMV-M infected citrus germplasm was propagated to different grapefruit, Valencia, Cara Cara, and evaluated in USHRL greenhouse and field. Currently, over 30 of the new planting with NMV-M infected plants are in the USHRL research farm. We believe that some of our six-seven years old field trial of grapefruits is better than others may attribute to NMV-M/CFL infection. Our new planting with NMV-M continued to show better outcome than control. We tried to use MNV-M infected sticks to graft-inoculated to existing matured Valencia citrus plants with very low rate of success. We have applied for a permit from APHIS to allow us to use agrobacterium-mediated inoculation to inoculate NMV-M infectious clone into existing citrus trees.
3) We tried to use the Asian citrus psyllids to transmit the NMV-M/CFL under control conditions. Although we can detect the NMV-M/CFL in different generation of psyllids after the first generation had been reared on the NMV-M/CFL infected plants. Its transmission capability remains to be seen in a longer period.
2. Please state what work is anticipated for next quarter:
We will continue to evaluate the old and newly planted NMV-M/infected grapefruits and sweet orange, respectively in the fields, and the psyllid transmission study. we will temporarily conclude this one-year project. 3. Please state budget status (underspend or overspend, and why): Due to hiring freeze, we were not able to hire an employee, therefore the budget was underspend.
3. Please state budget status (underspend or overspend, and why):
Due to hiring freeze, we were not able to hire an employee, therefore the budget was under spended.