Improved Diagnostic Techniques for Tomato Yellow Leaf Curl Virus in Tomato Breeding Programs.

Area of Science:

• Plant pathology
• Molecular biology
• Agricultural science

Background:

• Breeding tomatoes for resistance to tomato yellow leaf curl geminivirus (TYLCV) is challenging due to difficulties in accurately selecting resistant plants.
• Variability in genotypes (wild, wild-derived, and advanced lines) necessitates reproducible selection procedures in breeding programs.

Purpose of the Study:

• To evaluate serological and nucleic acid-based diagnostic techniques for TYLCV detection.
• To identify the most rapid and accurate combination of techniques for characterizing plant resistance levels.
• To establish a reliable selection system for TYLCV-resistant tomato breeding.

Main Methods:

• Evaluation of diagnostic techniques including squash blot, polymerase chain reaction (PCR), and triple antibody sandwich-enzyme-linked immunosorbent assay (TAS-ELISA).
• Comparison of sensitivity, reliability, and quantification capabilities of different methods.
• Assessment of hybridization methods for viral distribution analysis.

Main Results:

• Squash blot followed by PCR is recommended for screening asymptomatic Lycopersicon spp. due to extremely low viral concentrations undetectable by serological methods.
• Modified TAS-ELISA, combined with squash blot, is suitable for large-scale field screening of advanced breeding lines.
• Hybridization methods are superior to TAS-ELISA and PCR for assessing TYLCV distribution in plant tissues, including roots.

Conclusions:

• A combination of diagnostic techniques is crucial for accurate TYLCV resistance screening in tomato breeding.
• Squash blot and PCR offer a sensitive and reliable approach for identifying new sources of resistance.
• Optimized TAS-ELISA and hybridization methods can aid in large-scale screening and understanding viral spread.