Radiation-induced translocations in Prunus avium cv. Lambert

Abstract

Meiosis, pollen viability, and growth changes were investigated in two of six radiation-induced reciprocal translocation mutants of Lambert sweet cherry (Prunus avium L.).Meiosis in mutant 19-23-1CL was characterized by a quadrivalent which was evident from pachynema to metaphase I. A circle-4 configuration normally was observed, and alternate and adjacent configurations occurred with equal frequency. Pollen stainability tests indicated 28% normal pollen, as compared to 58% for the parental Lambert clone. Changes in growth habit were evident, the onset of meiosis and flowering were delayed, and only 2% of the blossoms set fruit. Any fruit retained was poor in color, noticeably pointed, and had a prominent longitudinal dorsal ridge.Meiosis in mutant 16-4E was more complex than in 19-23-1CL. Quadrivalents rarely were observed, and most meiocytes contained a trivalent and a centric fragment, or a univalent and centric fragment. Meiotic abnormalities associated with these defects frequently were evident throughout meiosis. Pollen stainability tests indicated about 34% normal pollen. No marked changes in growth habit, onset of meiosis or flowering were evident. Fruit drop was about four times that of normal Lambert. Fruit retained appeared normal.