Adaptability Factors for Open-field Tomato Production in East and West of Malaysia

This study concerns with climate resource management to improve open-field production of tomato in tropical lowlands of Malaysia. The objective was to use a model based approach for identifying optimum combination of growing season and location that is most adapted with different reference borders of temperature, relative humidity and vapor pressure deficit. Data were continuously collected every 60 seconds and for 12 months (January to December, 2014), from two major crop production sites in Seremban and Kota Kinabalu, respectively located in East and West of Malaysia. Interactions between simulated environment and growth responses of tomato were determined by means of an adaptability factor model for the purpose of comparing two locations at different months of year. Results of hypotheses testing that in each location, raw data does not vary with different months were rejected at any significant level, concluding that daily-averaged temperature, relative humidity and vapor pressure deficit were affected by different months. To identify the optimum group of days to be recommended as the best candidate growing seasons in each location, raw data were processed by an iterative algorithm that incremented desired growth response values in a tomato-growth model and calculated responses for each environment. Results showed that data from Kota Kinabalu had higher adaptabilities compared to Seremban. In addition, results of simulation indicated that for an open-field tomato production, the highest evapotranspiration rate will occur in the growing season that begins in March.