Efeitos da inoculação de Azospirillum em plântulas de Alface americana (Lactuna Sativa L.) cv Ariel

Abstract

Lettuce (Lactuna Sativa L.) is the main hardwood crop consumed in the world. Much has been studied to maximize its production without loss of quality and increased use of pesticides. In light of this, an alternative is the use of biostimulats containing plant growth promoting rhizobacteria (PGPR). The objective of this study was to evaluate agronomic characteristics in lettuce seedlings of the American type C.V. Ariel submitted to inoculation of bacteria of the genus Azospirillum. The experimental design was DIC with five treatments and four replicates. The treatments were Azospirillum (AbV-5 + AbV-6); Azospirillum (NC6 + NC8), Azospirillum (AbV-5 + AbV-6) x Azospirillum interaction (NC6 + NC8), Witness with sterilized substrate and Witness with unsterilized substrate. Leaf area (FA); Fresh dry matter (DMF), fresh dry matter (DMF), fresh dry matter (DMF), shoot dry matter (DMF), root dry mass (CLOA), chlorophyll B (CLOB), total chlorophyll (CLOT) and nitrate content (NO3). For the evaluated studies, the treatment containing Azospirillum (NC6 + NC8) presented AF of 250.28 cm² plant-¹ increment of 37% in relation to the control. For MFPA the treatment Azospirillum (NC6 + NC8) with 6.77 g plant-1 was not deferred from treatment Azospirillum (AbV-5 + AbV-6) x Azospirillum (NC6 + NC8). In MFR, the variation was from 4.75 to 3.15 g plant-1 in the treatments Azospirillum (NC6 + NC8) and Witness with sterilized substrate, respectively. In the MFT question with 11.5 g plant -¹ Azospirillum (NC6 + NC8) stood out statistically. In MSPA, the treatments Azospirillum (NC6 + NC8) and Azospirillum (AbV-5 + AbV-6) and Azospirillum (NC6 + NC8) stood out with 0.74 and 0.62 g plant -1. In MSR and MST, the increments of the best treatment in relation to the control were 42% and 45%, respectively. CLOB with 6.75 mg g-¹ fresh tissue and CLOT with 6.0 mg g-¹ fresh tissue Azospirillum (NC6 + NC8) was shown to be more efficient without statistically deferring treatment Azospirillum (AbV-5 + AbV-6) x Azospirillum (NC6 + CN8). For NO3 and CLOA none of the treatments had a significant response. Treatment with Azospirillum (NC6 + NC8) was more efficient in reaction to the other treatments.