BIOENERGETICS, MAINTENANCE RESPIRATION AND TRANSPIRATION OF PEPPER FRUITS

Structure and function of chile pepper Capsicum annuum var. annuum L. fruit tissues were examined by SEM, GC and porometry. Stomata were abs ent from the inner (endocarp) and outer (exocarp) epidermis of mature chile pepper fruits of cvs. Serrano, Jalapeno, Hungarian Wax, Anaheim and MexiBell. Fruit transpiration of 0.4 to 2.4 mmol H2O m(-2) s(-1) w as hence attributed solely to cuticular transpiration. Chlorophyll con tents of mature fruits ranged from 4.1 mu g/g to 76 mu g/g fresh weigh t with chlorophyll a:b ratios of 1.68:1 to 2.35:1. Locular space volum es and CO2 concentrations ranged respectively from 22% to 52% (v/v) an d from 0.6 to 2.1% CO2 with concomitant locular oxygen concentrations from 18.4 to 20.6% O-2 and RQ of between 0.89 to 1.81. Immature seeds and placenta were the primary sources of accumulated CO2, while respir ation of the endocarp was comparatively low. The large maintenance res piration from 0.81 to 2 mg CO2 [g dwt day](-1) and 0.54 to 1.3 mg gluc ose [g dwt day](-1) provided 0.05 to 1.3 kJoule fruit(-1) h(-1) for bi ochemical conversions.