Effects of magnesium remobilization and allocation on banana plant growth

ABSTRACT

Magnesium (Mg) is known as one of the mobile elements and can move from the lower to upper leaf blade when the plants suffer from Mg deficiency. It is generally recognized that symptoms of Mg deficiency appear on lower leaves. This study was conducted to reveal the effect of Mg deficiency stress on remobilization of Mg and nitrogen in banana plant and to collect the typical symptoms of Mg deficiency. Quartz sand cultures were used to study the effect of Mg deficiency on banana growth and its mobilization and allocation in the plants. Results showed that chlorosis, a typical symptom of Mg deficiency, occurs in the second leaf from top of banana plant after 35 days of Mg deficiency. Necrosis of the whole leaf in the middle part of banana and a significant reduction of leaf area from the top to middle leaves are detected. However, older leaves remain green, and their area is not affected. Mg is more stable in the banana plant and cannot be remobilized and transported from the old to young leaves under Mg deficiency. After 195 days of Mg deficiency, the growth and Mg nutrition of Mg-deficient plant can be normalized by the restoration of Mg nutrient after 49 days of deficiency. Therefore, Mg in banana leaves is not mobile and reusable from older to younger leaves.

KEYWORDS:

• Mg deficiency
• Mg mobilization and allocation
• Mg nutrition
• Mg restoration

Additional information

Funding

The authors would like to thank China's agricultural research system (CARS-31–06) for financial support.