The climactic conditions limit fruit production and quality in gulupa (Passiflora edulis Sims f. edulis) under integrated fertilization

The gulupa (Passiflora edulis Sims f. edulis) is one of the main fruit trees that are part of Colombia's export supply. The objective of this research was to determine the effect of chemical fertilizers alone (control) or together with integrated fertilization (humic acids or vermicompost; two separate treatments), on the yield and quality of gulupa fruit during two consecutive production cycles in the Colombian Amazon foothills. The climatic conditions were monitored and the phenological state of the plant was related to the average temperature, relative humidity, precipitation, solar radiation, and vapor pressure deficit. The integrated fertilization with vermicompost offered better values in productive parameters (fresh weight, number of fruits and equatorial diameter) irrespective of the cycle considered, but the fruit quality attributes were similar irrespective of the fertilization treatment tested. The fluctuations of the climatic variables of precipitation, relative humidity and solar radiation in both cycles (the second rainiest and affected by the ENSO phenomenon) reduced the quality of the fruit (whole fruit firmness by 19%, dry matter and pulp total titratable acidity by 24%, total soluble solids by 8%, individual sugars by 49%, organic acids by 63% and antioxidant capacity by 67%) as well as the productive parameters during the second cycle. These results demonstrate the high degree of influence exerted by the climate on productive and fruit quality attributes that are decisive in the production and marketing of the fruit. This research was supported by the Colombian Ministry of Science through the Bicentennial Doctoral Excellence Scholarship Program to F.M. Authors thank the technical staff of the Universidad Surcolombiana and the Universidad Nacional de Colombia who contributed to the development of this research. This work belongs to the doctoral thesis of F.M. supervised by Dr. M.S.H.G. and Dr. N.G.G. and is part of the collaboration agreement between the Sinchi Institute and the UPCT.