Development and production response of edible and forage varieties of pea (Pisum sativum L.) to temporary soil drought under different levels of phosphorus application

The change in weather conditions in Central Europe has led to the need to review current standards for fertilization of pulse crops. Physiologists claim that phosphorus may play a significant role in raising tolerance to a temporary lack of water in the soil. The objective of the 2-year field study (2011–2012) was to assess the effect of phosphorus application on characteristics of the aerial and underground plant parts of different varieties of pea and elements of their yield structure. The study showed that a higher phosphorus application rate led to significant intensification of photosynthesis and thus to more rapid vegetative development in the plants, manifested as a greater number of leaves and greater leaf area. The higher rate of phosphorus application significantly influenced the flowering process of pea during soil drought. The number of flowering nodes increased significantly as phosphorus application increased. The plants fertilized with the higher level of phosphorus produced a greater weight of root nodules with more Rhizobium bacterial colonies. Increased phosphorus fertilization had a significant role during the year of permanent semi-drought, 2012, resulting in a significantly greater number and weight of pods as well as a greater number and weight of seeds per plant, and thus a larger final yield.