Abstracts |
Soil salinity is a worldwide dilemma, restricting plant growth and production particularly in arid and semiarid regions. The study aimed to investigate the effects of arbuscular mycorrhizal (AM) fungus (Glomus deserticola Trappe & John) on growth, flower yield, salinity tolerance and mineral acquisition in kalanchoe (Kalanchoe blossfeldiana Poelin) plants under different levels of salinity. Mycorrhizal (+AMF) and mom-mycorrhizal (-AMF) kalanchoe plants were subjected to four levels of NaCl salinity (0, 50, 100 and 200 mM NaCl). Application of NaCl significantly reduced growth responses, flower parameters, mineral contents, and levels of mycorrhizal colonization of mycorrhizal and non-mycorrhizal kalanchoe plants comparing to control plants, mainly at high concentrations. However, the rate of reduction was more pronounced in non-mycorrhizal treated plants. Leaves of AM kalanchoe at the highest salt level were significantly greener (more chlorophyll) than those of the non-AM plants. Mycorrhizal kalanchoe plants had significantly higher biomass, plant heights, leaf area, flower yield, concentrations of nutrients (P, N, K, Ca and Mg) comparing to those non-mycorrhizal plants irrigated with or without NaCl. Although salinity reduced mycorrhizal colonization, the development of kalanchoe plants on mycorrhizal fungi was increased with increasing NaCl concentration in soil. Under salt stress, AM colonization had greatly reduced the mineral contents (Na and Cl) in leaf tissues of the Kalanchoe plants as compared to their equivalent non-mycorrhizal plants. Interestingly, AM inoculations significantly increased salt tolerance index (STI) as compared to non-AM plants. Results in this study suggest that AM fungi contribute to alleviate the deleterious effects of saline soils on growth and flower yield of crop ornamental plants by improving mineral contents, mitigation of NaCl-induced ionic imbalance and increasing the salt tolerance index of kalanchoe plants. |