Morphology of 'Crioula' guava seedlings under irrigation with increasing salinity water and nitrogen/potassium fertilization.

Several studies have been conducted evaluating the management of fertilizers as strategies to mitigate the deleterious effects of salt stress, so the objective of this work was to evaluate the quality of 'Crioula' guava seedlings under irrigation with water of different salinity levels and fertilized with combinations of nitrogen and potassium. The experiment was performed in a protected (screened) environment using a randomized block design and analyzed in a 5 × 4 factorial scheme, with four replicates, with the plot formed by two plants. The treatments were formed from the combination of the factor electrical conductivity of irrigation water (ECw 0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1), with the factor combinations (C) of nitrogen (N) and potassium (K2O) doses, being C1 = 70% N + 50% K2O, C2 = 100% N + 75% K2O, C3= 130% N + 100% K2O and C4= 160% N + 125% K2O. The recommended dose of 100% N and K, respectively, was 541.1 mg N dm-3 soil and 798.6 mg K dm-3 soil. The combinations of N and K fertilization corresponding to 70% N + 50% K2O and 100% N + 75% K2O of the recommended doses promoted greater growth of 'Crioula' guava seedlings. Water with ECw of 2.1 dS m-1 promotes the formation of quality 'Crioula' guava seedlings.

Morphology of 'Crioula' guava seedlings under irrigation with increasing salinity water and nitrogen/potassium fertilization / Morfologia de goiabeira 'Crioula' sob irrigação com águas de salinidades crescentes e adubação nitrogenada-potássica

Abstract Several studies have been conducted evaluating the management of fertilizers as strategies to mitigate the deleterious effects of salt stress, so the objective of this work was to evaluate the quality of 'Crioula' guava seedlings under irrigation with water of different salinity levels and fertilized with combinations of nitrogen and potassium. The experiment was performed in a protected (screened) environment using a randomized block design and analyzed in a 5 × 4 factorial scheme, with four replicates, with the plot formed by two plants. The treatments were formed from the combination of the factor electrical conductivity of irrigation water (ECw 0.3, 1.1, 1.9, 2.7 and 3.5 dS m-1), with the factor combinations (C) of nitrogen (N) and potassium (K2O) doses, being C1 = 70% N + 50% K2O, C2 = 100% N + 75% K2O, C3= 130% N + 100% K2O and C4= 160% N + 125% K2O. The recommended dose of 100% N and K, respectively, was 541.1 mg N dm-3 soil and 798.6 mg K dm-3 soil. The combinations of N and K fertilization corresponding to 70% N + 50% K2O and 100% N + 75% K2O of the recommended doses promoted greater growth of 'Crioula' guava seedlings. Water with ECw of 2.1 dS m-1 promotes the formation of quality 'Crioula' guava seedlings.

Resumo Diversos estudos vêm sendo desenvolvido avaliando o manejo de adubos como estratégias para mitigar os efeitos deletérios do estresse salino, neste sentido, objetivou-se com este trabalho avaliar a qualidade de mudas de goiabeira Crioula sob irrigação com águas de diferentes níveis salinos e adubadas com combinações de nitrogênio e potássio. O experimento foi conduzido em ambiente protegido (telado) utilizando-se o delineamento de blocos casualizados e analisados em esquema fatorial 5 × 4, com quatro repetições, com a parcela formada por duas plantas. Os tratamentos foram formados pela combinação do fator condutividade elétrica da água de irrigação (CEa), com valores de 0,3; 1,1; 1,9; 2,7 e 3,5 dS m-1; e o fator combinações (C) de doses de nitrogênio (N) e potássio (K2O), sendo C1 = 70% N + 50% K2O; C2 = 100% N + 75% K2O; C3= 130% N + 100% K2O e C4= 160% N + 125% K2O. A dose recomendada de 100% de N e K, respectivamente, foi de 541,1 e 798,6 mg de K dm-3 de solo. As combinações de adubação nitrogenada e potássica de 70% N + 50% K2O e 100% N + 75% K2O, em relação às doses recomendadas, resultaram em um maior crescimento de mudas de goiabeira Crioula. Água com CEa média de 2,1 dS m-1 foi capaz de promove a formação de mudas de qualidade de goiabeira Crioula.