64ª Reunião Anual da SBPC

E. Ciências Agrárias - 1. Agronomia - 4. Fitotecnia

EFFECT OF SILICON ON PEPPER PLANTS UNDER WATER DEFICIT

Emilly dos Santos Pereira 1 Talitha Soares Pereira 1 Daniele Viana da Costa 1 Railan do Nascimento Ferreira 1 Eldenira Barbosa Uchôa 1 Allan Klynger da Silva Lobato 2

1. Núcleo de Pesquisa Vegetal Básica e Aplicada, Universidade Federal Rural da Amazônia 2. Prof. M.sc./ Orientador- Núcleo de Pesquisa Vegetal Básica e Aplicada, Universidade Federal Rural da Amazônia

INTRODUÇÃO:

The pepper (Capsicum annuum L.) is an important spice plant belonging to the nightshade family. On worldwide scale, pepper culture has big economic importance it is widely used by the population of several countries. The world yield estimate Consists of two types of products, fresh, and in dehydrated form of condiment. In relation to productive performance of pepper plants, water deficit is a key a limiting factor to achieving adequate yield in protected cultivation or under field conditions. The silicon (Si) is an abundant element in terrestrial superficie, however its availability to plants is normally low. Silicon is considered a benefic element to higher plants with its absorption and deposition in cell walls of several organs such as leaf and stem can promote beneficial effects, and for this reason has been frequently linked to physiological, morphological, nutritional, and molecular aspects in plants. The objective of this study was to investigate the effect of silicon on transpiration rate of two Capsicum annuum cultivars exposed to the water deficit in different.

METODOLOGIA:

The study was carried out in the Instituto de Ciencias Agrárias (ICA) of the Universidade Federal Rural da Amazonia (UFRA), Belem city, Para state, Brazil (01°27’S and 48°26’W). The plants remained in green house without environment control, and minimum, maximum and medium temperatures were 22.1, 35.5, and 28.4°C, respectively. In this study were used seeds of pepper (Capsicum annuum L.) cvs. Ikeda and Vermelho Gigante. Substrate to plant growth was composed mix of sand and silic in proportion of 2:1, respectively, as well as this substrate was autoclaved at 120°C atm-1 by 40 min. The container used to the plant growing was pot type Leonard with 2 L capacity. The transpiration was evaluated in totally expanded leaves, under light and present in the medium third of the branch main, in which was used steady state porometer (LI-COR Biosciences, model 1600), with the gas changes evaluated immediately during the period between 10:00 and 12:00 h in all the plants of the experiment. Data were submitted to variance analysis and when significant differences occurred the Scott-Knott test at 5% level of error probability was applied. Standard errors were calculated in all evaluated points. The statistical analysis was carried out with the SAS software.

RESULTADOS:

The water deficit caused significant reduction in transpiration in Ikeda and Vermelho Gigante cultivars. Exogenous application of 0.25, 1.00, and 1.75 µM Si promoted attenuation of symptoms induced by water deficit. The treatments with added silicon were not statistically different. Silicon promoted attenuation in symptoms linked to water deficiency in transpiration rate, because during plant absorption in form of monosilicic acid (H4SiO4), silicon accumulates in the leaf, forming a layer double of silicon. This accumulation promotes a reduction in transpiration and decrease water loss by the plant, but still contributing to maintenance of adequate transpiration rate. In addition, the transpiration process in plants is carried out by the stomatal present in leaf and cuticle normally in stem. Agarie et al. (1998) found improvement linked to transpiration rates in Oryza sativa plants cultivated with Si. Similar results on maintenance of transpiration were reported previously by Lobato et al. (2009a) studying the protective action of silicon in Capsicum annuum under water deficit.

CONCLUSÃO:

This study revealed that application of silicon promoted attenuation in symptoms linked to water deficiency on transpiration rate in Capsicum annuum plants exposed to water deficit.

Palavras-chave: pepper, silicon, water deficiency.