The tomato production components of loss were identified and quantified in unheated greenhouse, in the summer-autumn period, evidencing the tomato critical production component and the loss key-factor, using the methodology of the crop life table. The experiment was conducted at the Universidade Federal de Viçosa, Minas Gerais State, Brazil, from January to June 2001 and consisted of two treatments (cultivar Santa Clara I 5300 and hybrid Débora Plus) in a randomized complete block design with 5 replications. During the tomato cycle, the number of dead plants, its causes and the number of flowers and fruits/plant were evaluated. At harvest, the healthy fruits were counted, weighted and classified; the causes of fruit damage were identified and the loss quantified. There was no significant difference between commercial yield of 'Sta. Clara' (40.18 t/ha) and 'Débora Plus' (54.98 t/ha). The classified yields between 'graúdos A' fruits ('Sta. Clara': 24.39 t/ha; 'Débora Plus': 32.32 t/ha) were not different either. The yield of 'médio extra' fruits ('Sta. Clara': 7.60 t/ha; 'Débora Plus': 10.77 t/ha) and the sum of 'médio especial' with 'pequenos' fruits ('Sta. Clara': 8.19 t/ha; 'Débora Plus': 11.90 t/ha) were low. Total losses were more influenced by fruits (r = 0.89) (P<0.01) than by any other production components. Consequently, fruits were considered the critical production component of tomato yield. Total fruit losses were more influenced by blossom-end rot (r = 0.97) (P<0.01) than by any other loss factors, being considered the loss key-factor in those conditions.
Lycopersicon esculentum; crop life table; blossom-end rot; integrated pest management
