Phloematic mobility of (10)Boron in kiwifruit (Actinidia deliciosa) mixed shoots

作者：Sotomayor Carlos^*; Ruiz Rafael; Munoz Luis

来源：Ciencia e Investigacion Agraria, 2012, 39(3): 563-567.

DOI：10.4067/S0718-16202012000300015

• Boron
• foliar absorption
• kiwifruit
• phloem mobility
• stable isotope

C. Sotomayor, R. Ruiz, and L. Munoz. 2012. Phloematic mobility of (10)Boron in kiwifruit (Actinidia deliciosa) mixed shoots. Cien. Inv. Agr. 39(3): 563-567. Boron (B) is an essential micronutrient showing restricted mobility in plants, except in species that synthesize polyols. The ability of kiwifruit to mobilize B through phloem transport has not yet been confirmed, despite its ability to synthesize the polyol myo-inositol. This study examined kiwifruit plants in which boric acid enriched with the stable B-10 isotope was applied to the distal leaves of mixed shoots with flowers. At 24, 72 and 144 h, both B-10-treated and un-treated leaves and flowers from treated shoots were sampled and subsequently analyzed via mass spectrometry to determine the resulting B-11/B-10 ratios. Control leaves and flowers showed a natural ratio, varying between 3.82 and 4.05. In contrast, the ratios in treated leaves were 1.57 at 24 h,h 2.06 at 72 h (both of which are significantly different from the control) and similar to the control again after 144 h, at 3.83h. In the flowers from shoots with treated leaves, the ratios were 1.31 at 24 h, h1.48 at 72 h (both different from the control) and 3.67 at 144 h (similar to the control). These results indicate that the B solution was absorbed through the leaves and then rapidly retranslocated to B-demanding sinks, such as flowers, within the first 72 h. This finding clearly indicates that kiwifruit can transport boron through the phloem, which is essential knowledge for the correction of leaf and flower B deficiencies through foliar applications.

• 出版日期2012-12