What nutrient deficiency may appear temporarily in tobacco transplants set in cool soils, despite adequate soil nutrient levels?

In the context of tobacco transplants, phosphorus deficiency can indeed manifest temporarily when transplants are placed in cool soils, even if soil nutrient levels are adequate. This occurs because phosphorus availability is highly temperature-dependent. In cooler soil conditions, the solubility and mobility of phosphorus decrease, which inhibits the plant's ability to take it up. Consequently, plants may show symptoms of deficiency, such as stunted growth or purpling, even though the actual phosphorus levels in the soil are sufficient.

Understanding that phosphorus is critical for energy transfer and root development can help explain the importance of its availability right after transplanting. In this scenario, the stress from cooler temperatures can temporarily limit the plant's uptake of phosphorus, leading to the observed deficiency symptoms. Therefore, monitoring soil temperatures and managing transplanting practices becomes essential for optimizing nutrient uptake in tobacco production.