PHOTOSYNTHESIS, GROWTH, AND YIELD IN STRAWBERRY WITH SHEEP MANURE COMPOST AND PEAT

Compost allows for sustainable handle of home organic residuals and decreases cost production of small-scale horticultural systems. The objective of this research was to analyze the effect of compost addition to soilless media on the growth, yield, and physiology of three strawberry cultivars. The Mexican cultivars ‘Jacona’ and ‘Zamorana’ and the commercial ‘Festival’ were grown inside a glasshouse on either of two media mixtures: peat+perlite (1:1; v/v) or compost+peat+perlite (2:1:1; v/v). Compost was made of sheep manure and the Steiner solution was the mineral source. Readings of photosynthesis rate, stomatal conductance, transpiration rate, SPAD units were performed periodically and dry weight from organs was determined six times. The addition of compost resulted in less total plant dry weight during the fruiting season and lower SPAD values throughout the experiment; however, photosynthesis was affected by compost only just before fruiting period compared with plants growing without compost. Dry matter remobilization during fruiting apparently explains the lack of effect of compost on total plant yield. As a conclusion, SPAD units and total plant dry matter are negatively affected by sheep manure compost during strawberry fruiting, but total plant yield is not affected by compost apparently explained by dry matter remobilization in the plant from roots and leaves to fruits.