Callose Formation and Subsequent Disappearance: Studies in Ultrasound Stimulation

Abstract

Callose synthesis in parenchyma and in sieve elements of cotton (Gossypium hirsutum var. Acala) seedling petiole was promoted by low-intensity ultrasound (850 kc) locally applied. Of several forms of deposits in parenchyma, pit callose was the most frequent. Where there was no gross petiolar injury and cells remained alive, no inhibition of subsequent growth could be clearly observed, and the callose eventually decreased to control levels. The results offer further evidence that callose can be induced to form and to disappear without bringing about irreversible injury.