Proline accumulation in sugarcane roots subjected to drought conditions

Resumo

Sugarcane cultivation faces various environmental stresses, among which drought is one of the most aggra­vating to production. As a result of this, we know that proline accumulation in cells is one of the factors respon­sible for drought-tolerance in plants. Thus, this paper aimed to evaluate accumulations in proline levels in the roots of two sugarcane cultivars subjected to drought, one of them tolerant (RB867515) and the other sensitive (SP86-155). The experiment was conducted in a greenhouse and the plants were subjected to 1, 3, 5, and 10 days of water deficit. The free proline level in tolerant sugarcane roots was statistically significant after 10 days of irrigation suppression, with an expressive difference of 25.43%, when compared to the sensitive plant. The greater accumulation of proline in the tolerant cultivar proved its drought-tolerant character; this osmoprotectant helped the plants to maintain their turgor after 5 days of water deficit (moderate stress) and to cope with a greater water deficit for 10 days (severe stress), when compared with the sensitive plant. The result from this paper indicates that the metabolism of proline accelerated the cell signaling processes which promoted cell and tissue turgidity, favoring the survival of the tolerant cultivar for a greater period of water deficit.