Judith Jeruto Kiptoo, Mustansar Mubeen, Hafiz Muhammad Usman, Aqleem Abbas, Kipsumbai Pixley, Emily Chemoiwa, Peris Wangari Nderitu, Rotich Godfrey, Gaudencia J. Kiptoo


Citrus fruit is considered a very nutritious and delicious diet. Citrus consists of lemon, oranges, mandarin, and grapefruit which have economic value in the world. Significant losses occur in citrus due to numerous diseases. Among various diseases, citrus trees are seriously affected by a phytopathogenic mollicute Spiroplasma citri which causes stubborn disease. S. citri is transovarially transmitted by several leafhopper species. Symptoms include smaller and cupped leaves, small size, crook fruits with aborted seeds. Moreover, irregularity on the fruits such as different sizes, shapes, and typically lighter, smaller fruits than its healthy counterpart has also been observed. The affected fruits often drop before maturity. The color inversion is often seen with the stylar end remaining green and the peduncle end showing color. Various molecular and biochemical tests are conducted to identify S. citri. Under in-vitro conditions, S. citri grows on SP4 media where a fried egg-like shaped colony is observed. Keeping the importance of the stubborn citrus disease, the present short note briefly described the symptomology, detection, transmission, and management.


Citrus stubborn; Spiroplasma citri; Detection; Management

Full Text:



Abd El-Fatah, W.H., Egiza, A.O., Youssef, S.A., Shalaby, A.A., 2016. Isolation andi dentification of Spiroplasma citri associated with citrus stubborn disease in Egypt. Internation Journal of Advanced Research in Biological Sciences 3, 223-231.

Anwaar, H., Iqbal, Z., Rehman, M.A., Mubeen, M., Abbas, A., Usman, H.M., Farhan, M., Sohail, M.A., Kiptoo, J.J., Iqbal, S., 2020. Evaluation of fungicides and biopesticides for the control of Alternaria black rot disease in citrus. Plant Cell Biotechnology and Molecular Biology 21, 118-126.

Bové, J.M., Garnier, M., 2002. Phloem-and xylem-restricted plant pathogenic bacteria. Plant Science 163, 1083-1098.

Fletcher, J., Melcher, U., Wayadande, A., 2006. The phytopathogenic spiroplasmas. The Prokaryotes: an evolving electronic resource for the microbiological community, 3rd ed. Springer, New York, pp. 905-947.

Gumpf, D.J., Calavan, E.C., 1981. Stubborn disease of citrus, Mycoplasma diseases of trees and shrubs. Elsevier, pp. 97-134.

Iftikhar, Y., Bakhtawar, F., Hussain, I., Sajid, A., Mubeen, M., Ahmad, M., Zeshan, M.A.S., Fatima, N., Umer, M., Iqbal, S., 2020. Detection of Spiroplasma citri causing citrus stubborn disease in Sargodha, Pakistan. International Journal of Botany Studies 5, 481-485.

Lee, D.R., Maung, C.E.H., Henry, A., Kim, K., 2019. Effect of large-scale cultivation of Bacillus amlyoliquefaciens Y1 using fertilizer based medium for control of Citrus Melanose causing Diaporthe citri. Korean Journal of Soil Science and Fertilizer 52, 84-92.

Lee, I., Bottner, K.D., Munyaneza, J.E., Davis, R.E., Crosslin, J.M., du Toit, L.J., Crosby, T., 2006. Carrot purple leaf: a new spiroplasmal disease associated with carrots in Washington State. Plant Disease 90, 989-993.

Mello, A.F.S., Yokomi, R.K., Melcher, U., Chen, J., Civerolo, E., Wayadande, A.C., Fletcher, J., 2010a. New perspectives on the epidemiology of citrus stubborn disease in California orchards. Plant Health Progress 11, 37.

Mello, A.F.S., Yokomi, R.K., Payton, M.E., Fletcher, J., 2010b. Effect of citrus stubborn disease on navel orange production in a commercial orchard in California. Journal of Plant Pathology, 429-438.

Mubeen, M., Arshad, H.M., Iftikhar, Y., Bilqees, I., Arooj, S., Saeed, H.M., 2015a. In vitro efficacy of antibiotics against Xanthomonas axonopodis pv. citri through inhabitation zone techniques. International Journal of Agriculture and Applied Sciences 7, 67-71.

Mubeen, M., Arshad, H.M., Iftikhar, Y., Irfan Ullah, M., Bilqees, I., 2015b. Bio-chemical characterization of Xanthomonas axonopodis pv. citri: a gram negative bacterium causing citrus canker. International Journal of Science and Nature 6, 151-154.

Roistacher, C.N., 1991. Graft-transmissible diseases of citrus: Handbook for detection and diagnosis. Food & Agriculture Organization.

Shi, J., Pagliaccia, D., Morgan, R., Qiao, Y., Pan, S., Vidalakis, G., Ma, W., 2014. Novel diagnosis for citrus stubborn disease by detection of a Spiroplasma citri-secreted protein. Phytopathology 104, 188-195.

Umar, U.D.U., Naqvi, S.A.H., Ahmed, I., Rehman, A., Zulfiqar, M.A., Ullah, S., Pasand, S., Khan, Z., Rehman, A., 2020. Prevalence and serological detection of Spiroplasma citri, a cause of citrus stubborn disease in southern Punjab, Pakistan. Pakistan Journal of Agricultural Research 33, 748-753.

Wei, W., Davis, R.E., Mowery, J.D., Zhao, Y., 2021. Growth inhibition of phytopathogenic spiroplasmas by membrane‐interactive antimicrobial peptides Novispirin T7 and Caerin 1.1. Annals of Applied Biology,

Yokomi, R.K., Mello, A.F.S., Saponari, M., Fletcher, J., 2008. Polymerase chain reaction-based detection of Spiroplasma citri associated with citrus stubborn disease. Plant Disease 92, 253-260.



  • There are currently no refbacks.