Aim

Agronomic biofortification of fruit with iodine (I) has become an innovative approach in contemporary agriculture. In this study, we evaluated the influence of soil- and foliar I applications on absorption of this nutrient by apple (Malus domestica Borth.) trees, as well as on growth and yield responses of the plants.

Methods

In 2018–2019, ‘Red Jonaprince’ apple trees, grown on sandy loam soil, were treated with potassium iodide (KI) or K-iodate (KIO₃) through soil application (at a rate of 4 kg, 8 kg or 12 kg I ha⁻¹) or preharvest sprays (at a rate of 0.5 kg, 1 kg or 1.5 kg I ha⁻¹).

Results

The I sprays increased apple I contents to the targeted range of 50–100 µg 100 g⁻¹ fresh weight and even to the recommended daily intake of I for adults (the KI sprays at rates of 1 kg and 1.5 kg I ha⁻¹). Although the I sprays caused leaf injuries, they did not affect tree growth and yield. However, the spray of KI and KIO₃ at the highest rate decreased the soluble solid concentration in fruit. For soil-supplied trees with I, an increase in apple I concentration was found only in the first year of the study.

Conclusions

Apple tree is a suitable target plant for agronomic I biofortification, and from the economic point of view, the spray of KI or KIO₃ at a rate of 0.5 kg I ha⁻¹ should be recommended in orchards.

中文翻译：

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在苹果的生物强化方面，收获前高剂量的碘喷雾比土壤施用更有效

目标

用碘 (I) 对水果进行农艺生物强化已成为当代农业的一种创新方法。在这项研究中，我们评估了土壤和叶面施用 I 对苹果（Malusdomesica Borth.）树吸收这种养分的影响，以及对植物生长和产量响应的影响。

方法

2018-2019 年，生长在沙壤土上的“红乔纳普林斯”苹果树通过土壤施用（以 4 公斤、8 公斤或 12 公斤的比例）用碘化钾 (KI) 或碘酸钾 (KIO ₃ ) 处理I ha ^-1 ) 或收获前喷洒（以 0.5 kg、1 kg 或 1.5 kg I ha ^-1的比率）。

结果

I 喷洒将苹果 I 含量增加到 50–100 µg 100 g ^-1鲜重的目标范围，甚至达到了成人每日 I 的推荐摄入量（KI 喷洒率为 1 kg 和 1.5 kg I ha ^-1） . 尽管 I 喷剂造成了叶片损伤，但它们并没有影响树木的生长和产量。然而，以最高速率喷洒KI和KIO ₃降低了果实中的可溶性固形物浓度。对于有 I 的土壤供应树木，仅在研究的第一年发现苹果 I 浓度增加。

结论

苹果树是适合农艺I生物强化的目标植物，从经济角度来看，建议在果园中以0.5 kg I ha ^-1的比例喷洒KI或KIO ₃。