EFFECT OF BLACK LEAF MOLD (PSEUDOCERCOSPORA FULIGENA) EPIDEMICS ON HOST GROWTH PARAMETERS OF TOMATO (SOLANUM LYCOPERSICUM) GROWN UNDER PROTECTED CULTIVATION IN THAILAND

Z. Mersha, B. Hau
Effect of black leaf mold (P. fuligena) on host dynamics of a fresh market tropical tomato (S. lycopersicum ‘FMTT260’) was studied in four plantings (A to D). Black leaf mold (BLM) epidemics were the highest during plantings B and C (August and September 2005, respectively) followed by that of D (November 2005). Epidemic of the planting A in July 2005 was the lowest. The highest peaks (plantings B and C) and that of lower epidemic from planting D corroborated with the seasonal classification of central Thailand as hot-wet and cool-dry seasons, respectively. On the other hand, it was most likely that the level of inoculum played a role for the low epidemics of the planting in June 2005. In all cases, disease incidence and severity fitted well to logistic functions with R2 > 0.98. At times of peak epidemics, a clear effect of reduced host growth in terms of healthy leaf area (HLA) was discernible from a comparison of treatments with (F) and without (NF) fungicide spray. A mean severity of 0.3 (proportion) from the NF treatments of the two peak epidemics resulted in an average of 68% loss of HLA. Furthermore, a respective loss of 11% and 50% was encountered when healthy leaf area index (HLAI) from healthy plants (HLAIHP) was compared with that of fungicide sprayed (HLAIF) and non-sprayed (HLAINF) once. Overall, 2 applications of mancozeb at 4 and 6 weeks after transplanting significantly reduced the disease (60-90%). BLM, however, did not significantly affect other host parameters such as plant height and total leaf number.
Mersha, Z. and Hau, B. (2009). EFFECT OF BLACK LEAF MOLD (PSEUDOCERCOSPORA FULIGENA) EPIDEMICS ON HOST GROWTH PARAMETERS OF TOMATO (SOLANUM LYCOPERSICUM) GROWN UNDER PROTECTED CULTIVATION IN THAILAND. Acta Hortic. 808, 33-40
DOI: 10.17660/ActaHortic.2009.808.3
https://doi.org/10.17660/ActaHortic.2009.808.3
black leaf mold, epidemics, P. fuligena, S. lycopersicum 'FMTT260', host growth, healthy leaf area index
English

Acta Horticulturae