Ethylene regulates common bean root growth in adaptation to P deficiency

Abstract

Root types of common bean may differ in response to P deficiency. Ethylene is known to be involved in plant response to nutritional stress, including P deficiency, but little is known about its roles in root responses to P deficiency. Six genotypes of common bean were planted in solid media for 3 weeks, and two of them were planted in germination paper and hydroponics with 3 harvests under two P levels. Ethylene production in different type of roots at different plant ages was measured. In general, ethylene production of three root types was higher in low P than that in high P, and ethylene production also differed with root types, root age, and genotypes. Ethylene is produced more in certain root types at stages showing more response to P stress. Our data suggested that ethylene regulates common bean root response to P stress, and this regulation mainly occurs in the newest, most active root type.