Coffee leaf and stem anatomy under boron deficiency

Revista Brasileira de Ciência do Solo

Ciro Antonio Rosolem²  Vagner Maximino Leite¹ 

[1] ,Universidade Estadual Paulista Faculdade de Ciências Agronômicas Departamento de Produção VegetalBotucatu SP

关键词: boron deficiency;    Ca/B ratio;    coffee nutrition;    stomata;    deficiência de boro;    relação Ca/B;    nutrição do cafeeiro;    estômatos;   

DOI  :  10.1590/S0100-06832007000300007

来源: SciELO

【 摘 要 】

Boron deficiency in coffee is widely spread in Brazilian plantations, but responses to B fertilizer have been erratic, depending on the year, form and time of application and B source. A better understanding of the effects of B on plant physiology and anatomy is important to establish a rational fertilization program since B translocation within the plant may be affected by plant anatomy. In this experiment, coffee plantlets of two varieties were grown in nutrient solutions with B levels of 0.0 (deficient), 5.0 µM (adequate) and 25.0 µM (high). At the first symptoms of deficiency, leaves were evaluated, the cell walls separated and assessed for B and Ca concentrations. Scanning electron micrographs were taken of cuts of young leaves and branch tips. The response of both coffee varieties to B was similar and toxicity symptoms were not observed. Boron concentrations in the cell walls increased with B solution while Ca concentrations were unaffected. The Ca/B ratio decreased with the increase of B in the nutrient solution. In deficiency of B, vascular tissues were disorganized and xylem walls thinner. B-deficient leaves had fewer and deformed stomata.

【 授权许可】

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