Efeito do déficit hídrico em parâmetros bioquímicos e fisiológicos de Allium sativum L.

Abstract

The popular garlic Allium sativum L. is a culture known worldwide for its medicinal, culinary and ecological properties of agricultural pests. With this it is relevant the study of this plant in relation to the adaptability to the climatic changes. Warm temperatures are expected in the future and with few rainfall, damaging the ecosystem in general. Then the garlic may be affected by these adverse conditions. Thus, the objective of this work was to evaluate the effect of water deficit on the physiological and biochemical aspects of garlic submitted to water deficit. The experiment was conducted at the Federal University of Southern Frontier Campus Laranjeiras do Sul, in a greenhouse between April and July 2017, cold season of the year. The garlic seeds were purchased from the farmers of Nova Laranjeiras. The water deficit level adopted was 100% of the pot capacity, 75%, 50% and 25%, being weighed and irrigated the pots every two days. Plantmax® substrate was used for planting. During the water deficit, analyzes were performed with the porometer and chlorophyll meter. After 45 days of treatment, the plants were harvested and evaluated the physiological and biochemical parameters being 5 replicates for each treatment. The biochemical parameters: Guaiacol peroxidase (POD) and ascorbate peroxidase (APX) enzymatic activity and proteins, were then submitted to physiological parameters: fresh and dry biomass (g), bulb, root and leaf growth (cm) all treatments to the completely randomized design. Protein increase was observed in bulbiles, POD enzyme activities in the roots and APX in garlic leaves during the water deficit. The chlorophyll index was reduced only in the 50% treatment with yellowing of the leaves. Garlic growth had an increase in the treatment of 75% of the pot capacity when compared to the control (100%) for the leaves, not obtaining significant growth for root and bulb. The fresh and dry biomass for the treatments 25% and 50% were obtained results smaller than when compared to 100%. Concluding that the garlic plants are not tolerant to the water deficit, in this way this plant will suffer from the climate changes foreseen for the future. Key words: Allium sativum L., climate change, water deficit, adaptation.