Salinity and silicon in vegetative growth and pigment concentration in four fig cultivars (Ficus carica L.)

The fig tree (Ficus carica L.) is a Mediterranean plant appreciated for its high organoleptic quality fruits and high commercial value, which are rich in nutrients and antioxidant compounds. Salinity is one of the main factors affecting crop production, however, the application of silicon has shown positive effects on plants subjected to salinity. In this work the effects of salinity and silicon were evaluated on vegetative growth and leaf pigment concentration of four fig cultivars: 'Brown Turkey', 'Kadota', 'Black Mission' and 'Adriatic'. These plants were treated daily with a solution of 50 mg L-1 of silicon in the propagation phase. Subsequently, in the growth phase, the plants were subjected to foliar applications of a solution of 50 mg L-1 of silicon and irrigated with saline solutions of 1 dS m(-1), 5 dS m(-1) and 10 dS m(-1). Fig varieties varied in budding, rooting and overall plant growth. Salinity negatively affected plant growth, while silicon favored growth and increased concentration of photosynthetic pigments. An electrical conductivity equal to or less than 5 dS m-1 did not pose problems for the initial growth of this fruit, while the application of silicon showed beneficial effects regardless of cultivar and electrical conductivity, especially when applied by irrigation in the propagation phase.