Chlorophyll and carbohydrates in arachis pintoi plants under influenceofwater regimes and nitrogen fertilization

Abstract

In this experiment the chlorophyll and carbohydrate contents of Arachis pintoi were evaluated to verify if the presence of nitrogen in the soil could contribute to the effectiveness of the establishment of this legume. The design was completely randomized, in a 4 × 4 factorial arrangement, with four N rates (0, 40, 80 and 120 kg ha-1) and four irrigation levels (25, 50, 75 and 100% of fieldcapacity),withfourreplications.Thebiochemicalevaluationsofchlorophyllsa and b and total chlorophyll and total soluble sugars, sucrose and starch were performed. The highest contents of chlorophyll a and b and total chlorophyll in leaves were found at the dose of 120 kg ha-1. The water regime of 25% of fieldcapacitywasresponsibleforthelowest content of reducing sugars and total soluble sugars in leaves, stolons and roots. In the roots, the sucrose contents were higher in these conditions, which can be associated with a slight tolerance of the plant to water stress. The water deficiencywasresponsible for the decrease of reducing sugars and total N in the whole plant and positively influencedthelevelsofchlorophylland sugars in the stolon, promoting growth, especially of shoots, at the beginning of establishment. © 2013 Sociedade Brasileira de Zootecnia.