Interactive effects of excess boron and salinity on histological and ultrastructural leaves of Zea mays amylacea from the Lluta Valley (Arica-Chile)

Abstract

Maize is widely cultivated throughout the world, and more maize is produced each year than any other grain. Studies on the response of maize to salinity have typically focused on physiological aspects, but few studies have addressed the effects of salinity on the anatomical and ultrastructural characteristics of different plant organs. We analyzed the cell structure and changes in tissue organization in young leaves of Zea mays L. amylacea as a consequence of high salt and boron (B) levels. Plants were treated in nutrient solutions for 20 days with concentrations of 100 mM NaCl (Low salinity, L) or 430 mM NaCl (High salinity, H) in the case of saline treatments or with an excess of B supplied as boric acid to obtain 20 mg (334 µM) or 40 mg (668 µM) B kg -1 . The application of B under no salt and low salinity conditions did not result in ultrastructure changes in mesophyll cells (MC) or bundle sheath cells (BSC). The high salinity conditions the amylacea leaf cells showed some alterations in MC chloroplasts, which appeared swollen and rounded. The BSC chloroplasts lost their perpendicular disposition to the cell wall. Moreover, the absolute absence of plastoglobuli could indicate a greater resistance to oxidative damage.

Determination of ion content and distribution in leaf and root in adult plants of "lluteño" maize (Zea mays L.) of the XV Región of Arica and Parinacota, Chile

“…The bundle chloroplasts sheath cells change their perpendicular disposition to the cell wall and appear horizontally. Moreover, absolute absence the plastoglobuli, could indicate a greater resistance to oxidative damage (Bastías et al, 2013). The studies cited above have been carried out under controlled conditions of growth and inert substrates and pots, however, the results presented in this study were collected in real conditions of growth in the field.…”

Response of Maize (Zea mays L.) to Drought under Salinity and Boron Stress in the Atacama Desert

“…Due to these environmental factors, the agronomic productivity in the region is limited to a bunch of relatively salt-tolerant ecotypes or local varieties. In this sense, the maize ecotype “lluteño” is adapted to the Lluta valley, where high levels of salinity and B excess in the soil and irrigation water are found [ 14 , 15 , 16 ]. This sweet maize has shown remarkable tolerance to salinity and high B content due to continuous selection by the farmer in this valley [ 17 ].…”

Interação cálcio e boro na fixação biológica de nitrogênio na soja: avaliação morfológica, ultraestrutural e da atividade da nitrogenase

“…As causas para que ocorram estas alterações podem ser diversas, como exemplo podemos citar os choques de temperatura (HUANG et al, 2013), bem como o estresse hídrico (ZHANG et al, 2015), salinidade (BASTÍAS et al, 2013), doenças (SUZUKI et al, 2003) e por fim, fatores relacionados a nutrição mineral de plantas Avaliando os efeitos da deficiência de B na ultraestrutura da parede celular, em dois cultivares de Brassica Napus (mais e menos tolerantes à deficiência de B), Pan et al (2012) constataram que a deficiência de B provocou alterações na estrutura da parede celular das folhas, especialmente no cultivar menos tolerante à baixas doses de B, tornando-se esta mais espessa e inchada em comparação com a parede celular das plantas cultivadas com a dose controle de B (25 µmol L -1 ). Soma-se a isso que a lamela média nas células das folhas deficientes em B apresentou ainda alterações estruturais, possivelmente devido a aberrações ocorridas durante a síntese de pectina.…”

“…Por outro lado, Bastías et al (2013) perfazendo um total de 13 combinações (3,125B e 1,75Ca; 3,125B e 4,25Ca; 3,125B e 7,25Ca; 6,25B e 3,0Ca; 6,25B e 5,5Ca; 12,5B e 1,75Ca; 12,5B e 4,25Ca; 12,5B e 7,25Ca; 25B e 3,0Ca; 25B e 5,5Ca; 50B e 1,75Ca; 50B e 4,25Ca e 50B e 7,25Ca), as quais foram distribuídas segundo o delineamento experimental de blocos ao acaso, com quatro repetições. 2 2 2 2 2 2 2 2 2 2 2 2 2 H 3 BO 3 0,01 mol L…”