Modeling the impact of climate change on growth and yield of tomato

Abstract

Tomato is the world’s largest vegetable crop. It is one of the most important vegetable crops cultivated for its fleshy fruits and it is considered as important commercial and dietary vegetable crop. The average productivity of tomato in our country is nearly 158q per hectare. Its successful production in the tropics is, however, constrained by environmental variations especially under open field conditions. The rising temperatures and carbon dioxide concentration and uncertainty in rainfall associated with climate change may have serious direct and indirect consequences on crop production and hence food security. Objective of the study were Modeling of growth and yield of tomato and the impact of climate change based on projected climate change scenarios using DSSAT 4.5 model and the impact of climate change will be studied based on projected climatic scenarios (RCP.2.6, 4.5, 6.0 and 8.5). The field was designed as spilt plot under 3 growing situations (S1-poly house, S2-rain shelter, S3-Open condition) at Central Nursery, Vellanikkara. The date of planting was on 2014 December 1st, 10th, 2015 January 10th and 20th. The variety chosen was Anagha. The date of transplanting and growing environment had a significant effect on the various morphological, Phenological and yield parameters. Then greatest height was obtained by polyhouse (251.7cm) on 01 December 2014.The greatest biomass accumulation (2.23 t ha-1) inside the polyhouse on 10 December 2014 and 10 January 2015. The crop transplanted in polyhouse on 01 December 2014 had the longest duration of 114 days. Maximum LAI was recorded in the crop transplanted inside the polyhouse, rain shelter (20 January 2015) and open field (10 December 2014). Highest yield 111.5 t ha-1 in the crop transplant inside polyhouse on 01 December 2014. DSSAT model was validated and gave good RMSE values. The results also showed that the effect of minimum temperature would drastically reduce the yield. The increasing atmospheric CO2 concentration is likely to have some positive effect on yield, but the effect is not significant compared to the negative impact of rise in temperature. The yield of tomato (Anagha) will be reduced considerably due to climate change.