Rezultate parţiale privind comportamentul liniei de porumb SR8 pe soluri sărăturate

Abstract

Soil salinity affects plant production in many parts of the world. The predominant salt in most saline environments is NaCl. The two principal adverse effects of salinity in non-tolerant plants are i) osmotic stress and ii) Na /Cl- toxicity. Maize is considered a moderately salt-sensitive plant. The development of salt-tolerant crops is important because there are 955 million hectares of saline soils worldwide. Experiments were conducted using an salt-tolerant line developed in the Institute of Plant Nutrition, Justus-Liebig University, Giessen, Germany. The aim of this study was to elucidate the reactions of an inbred line (SR-8) to salt stress under NE-Moldavian growth conditions in comparison to the inbred line Pioneer 3906. The plants were grown in saline soil exhibiting an electrical conductivity of 8 dS/m. Injured leaves due to saline excess have not been detected during the growth period. The plants of hybrid Pioneer 3906 are characterized by a bigger size then the plants of SR-8 line and the difference is, 42,97 cm, on the average. Soil salinity has induced a decrease in the lenght of the corn cob ( with 8.8 %) only to the hybrid Pioneer 3906, while the corn cob of the line SR8, didn’t suffer any modifications due to the soil salinity. The number of the grains decreased due to the saline exces in both hybrid 3906 and line SR8. The mass of the line SR8 of the plants cultivated on a normal soil increased compared to those exposed to the salin exces, the production per plant remaining practically unmodified. The fact that the saline exces decreases only the production of hybrid Pioneer 3906 and not the one of the SR8 line leads to the conclusion that the plants of the line SR8 have a greater capacity for adaptation to this stress factor and that the salts exclusion mechanisms are more efficiently on this line comparing with the hybrid 3906.