Germination and initial growth of crambe (Crambe abyssinica Hochst.) under saline conditions

Abstract

Crambe is a promising crop for Brazil owing to its tolerance to drought and its short growing season (particularly if cultivated between seasons). However, the salinity tolerance of the unique Brazilian cultivar is not yet known. In this study, we aimed to determine the effects of different salinity levels on germination and initial growth of crambe cultivar FMS Brilhante. Therefore, an experiment was carried out in a completely randomized block design, during 19 days under greenhouse conditions. The treatments consisted of six levels of electrical conductivity of the soil saturation extract (EC): 2.50, 3.15, 3.35, 4.25, 5.75 and 9.55 dS m-1, obtained by adding sodium chloride (NaCl) to soil. It was evaluated germination, germination speed index (GSI), length of roots and dry mass of shoot and roots. Overall, germination and GSI increased under low levels of salinity - up to 3.77 dS m-1, caused by a possible break effect in seed dormancy. The initial growth was more sensitive to salinity than seed germination and the shoot dry matter decreased linearly with increasing salinity levels, indicating that FMS Brilhante cultivar is moderately sensitive to salinity.