FOLIAR APPLICATION OF ADENOSINE INCREASES FRUIT SIZE OF SOLANUM LYCOPERSICUM, CITRUS RETICULATE, AND PERSEA AMERICANA

Abstract

Adenosine applied daily to the root zone of 'Super Sweet 100' cherry tomato plants (Solanum lycopersicum) in 5 kg of soil mix in 9.5-L plastic pots over a 75-day growing period (3.25 µg/plant) significantly increased total fruit number per plant 1.9- and 2.3-fold and fruit diameter 1.6- and 1.7-fold compared to untreated control plants in two separate experiments, respectively. A single annual foliar application of adenosine (58 g/ha) to 'Fina Sodea' Clementine mandarin (Citrus reticulate) trees in a commercial orchard when fruit were 25 mm in diameter (July, during exponential fruit growth) significantly increased 3-year cumulative yield of fruit of packing carton sizes large (57.2-63.5 mm transverse diameter) and jumbo (63.5-69.9 mm) as both kilograms and number of fruit per tree, without reducing total yield in any year of the study, compared to untreated control trees. The result was a net increase of 5.1 11-kg cartons of commercially valuable large fruit per tree. Two foliar applications of adenosine (58 g/ha) alone, or with triiodobenzoic acid (58 g/ha), to 'Hass' avocado (Persea Americana) trees in a commercial orchard prior to periods of exponential fruit growth in summer (July) and in spring (January) of the high-yield on-crop year resulted in a net increase of 4,424 and 5,750 kg of large size fruit (213-269 g/fruit) per hectare, respectively, with no reduction in total yield in the treatment year or following year compared to untreated control trees. The two treatments increased 2-year cumulative yield of large size fruit by 4,908 and 7,163 kg per ha, respectively. Adenosine has significant potential to increase grower income by increasing fruit size without reducing total yield or fruit quality.