Multiple crowns are a common disorder that can be of genetic or environmental origin. Multiple crowns increase the size of the fruit core and result in flattening of the upper portion of the fruit, which reduces the value of the fruit for the fresh market and for canning. Collins (1960) states that fasciation - an abnormal growth resulting in two to numerous crowns - is relatively uncommon in 'Smooth Cayenne' and 'Queen,' but common in 'Singapore Spanish' and 'Pernambuco'. Collins (1960) also reported the existence of mutant clones of 'Smooth Cayenne' that produced 50% or more fruit with multiple crowns.
Environmental conditions that promote the multiple-crown disorder are high fertility and rapid growth following a period of prolonged drought, if such conditions occur about the time of inflorescence initiation (Collins, 1960; Py et al., 1987). An increased incidence of multiple crowns is correlated with periods of high irradiance and high temperature that occur during early inflorescence development, although the disorder is generally thought to be due to high temperature injury. Increased planting density reduced the incidence of multiple crowns (Linford and Mehrlich, 1934; Norman, 1977; Scott, 1992), presumably because mutual shading in the more dense plantings reduced the temperature of the reproductive apex. The significance of this shading effect is confirmed by the observation that there was a higher incidence of deformed crowns on outside rows than in the interior of a field. Irrigation during inflorescence development reduced the incidence of multiple crowns (Py et al., 1987).
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