Sugarcane mosaic virus (SCMV) is one among many viruses that infect sugarcane, cause yield loss, and become serious disease agents on sugarcane plantations. Since the morphological symptoms of SCMV are similar to other symptoms caused by Sugarcane streak mosaic virus (SCSMV) or nitrogen deficiency, the detection of SCMV is important through accurate diagnostic-like ELISA or RT-PCR. This research aimed to study the causative mosaic pathogen of SCMV in East Java, Indonesia, including mosaic development. The results showed that the mosaic symptom is present in all sugarcane plantations with 78% and 65% disease incidence and severity, respectively. Moreover, the detection procedure based on an amplification of cDNA of the coat protein gene sequence confirmed that SCMV was the causative agent of mosaic disease on sugarcane. Re-inoculation of healthy sugarcane plants with plant sap from a symptomatic leaf from the field showed similar mosaic or yellowish chlorotic areas on the leaf blade, and appeared on the fourth leaves upward from the inoculation leaf, in addition to showing different levels of peroxidase but not total phenol. Mosaic also correlated with the amount of total chlorophyll. Although Sucrose phosphate synthase (SPS) protein accumulation and activity were at a lower level in infected leaves, sucrose accumulation was at a higher level in the same leaves.

Sugarcane Mosaic Virus (SCMV) infection is one of the most serious problems that can result in severe yield loss of sugarcane. Since the symptoms of SCMV infection are similar to other biotic and abiotic stress symptoms, the development of a rapid diagnostic with high precision is required. The use of laboratory animals such as rabbits is required for antibody production in immunoassay‐based detection. However, due to its many advantages, specific chicken egg yolk immunoglobulin (IgY) has received considerable attention as an alternative antibody production in immunodiagnostics for infectious diseases. In this study, IgY antibody against SCMV recombinant coat protein (CP) was successfully obtained from chicken blood serum and tested to compare its efficacy against antibody from rabbit (IgG) using immunocapture reverse transcription‐polymerase chain reaction (IC‐RT‐PCR). The result showed that IgY and IgG could detect 0.1 g SCMV infected leaves using 1000‐times‐diluted antibodies. The IgY antibody was also confirmed to be reproducible and potentially applicable in plant disease diagnostics using an antibody‐based detection.