Ribonucleases in leaves and roots of Triticum durum and x Haynaldoticum sardoum submitted to low non freezing temperatures

In wheat leaf and root crude extracts several RNases can be distinguished b y pH optima analysis, and SDS-PAGE and activity staining. One acidic RNase (approximately 20 kD in size) and a group of neutral RNases have been ident ified by electrophoretic separation. Neutral RNases can be divided into sal t-stimulated (about 24 and 26 kD) and salt-inhibited (about 27 kD). Followi ng low temperature treatment, acidic and neutral salt-inhibited RNases rema in unchanged, while the neutral salt-stimulated RNases with higher mobility generally increase with respect to the control.