Mycorrhizal associations play a crucial role in afforestation efforts, as they enhance the acquisition of nutrients and water, thereby supporting seedling establishment. However, the influence of nitrogen (N) forms in the soil, particularly the organic N, on the formation of mycorrhizal associations and their subsequent effects on seedling morpho-physiology remains poorly understood. In this study, we examine the mycorrhizal colonization, along with morpho-physiological and functional traits, in Pinus cooperi seedlings following fertilization with organic N in controlled nursery conditions. A factorial experiment was performed with Pinus cooperi C. E. Blanco seedlings using two N sources: organic N (amino acids) and inorganic N (NH4NO3) and two N doses: low and high (60 vs 200 mg N seedling-1). Seedlings were inoculated with a mixture of native fungi, but the phylogenetic analysis showed that Suillus placidus (Bonord.) Singer was the only species colonizing roots. Organic N promoted similar morphology and nutritional status as inorganic N, though at a low N rate, it improved root growth and mycorrhizal colonization. High N fertilization improved seedling growth and nutritional status but reduced mycorrhizal colonization. Mycorrhizal colonization improved needle P concentration, delayed plant desiccation, and reduced root cellular damage when seedlings were subjected to desiccation, though it decreased plant growth and needle N concentration. We conclude that organic N fertilization improves mycorrhization of P. cooperi with S. placidus, but the fertilization dose should be adjusted to meet species-specific requirements in order to optimize plant quality and promote afforestation success.
Fertilizers play a crucial role in enhancing the productivity of plants. However, low nutrient use efficiencies of conventional fertilizers (CFs) associated with several losses have led to widespread multi-nutrient deficiencies in the soil and lower productivity. Furthermore, their excess application has caused serious damage to the soil and environment. Recently, nanotechnology has broadened its applicability in plant nutrition and has paved a way for the production of nanoparticle-induced fertilizers. Therefore, nanofertilizers stand out as promising alternative to CFs for sustainable agriculture. Nanofertilizers are composed of nanoparticles that contain macro- and micronutrients and deliver them in a controlled way to the plant's rhizosphere. This contributes to the enhanced nutrient utilization efficiency. This review delves into the effect of nanotechnology-based nanofertilizers in different forms and dosages on soil properties and plant development. Additionally, the mechanism underlying absorption of nanofertilizers and their advantages and limitations have also been discussed. A thorough comparison between conventional and nanofertilizers has also been made in this review in terms of their nutrient delivery mechanism, efficiency and application. As the use of nanoparticle-embedded fertilizers in plant nutrition is still in its infancy, this review can serve as a guide for future investigations to enhance the knowledge of the use of nanoparticles in the mineral nutrition of different crops.
Introduction Reduced water content in the soil triggers physiological, biochemical, and morphological damage to plants, aggravated by nutritional deficiency. One possible strategy to mitigate this damage comprises the use of silicon (Si). This study investigated whether Si can mitigate the damage caused by water deficit through nutritional mechanisms in bean plants grown under field conditions. Furthermore, it investigated whether the effectiveness of Si is influenced by water availability in the soil and the Si dose supplied.Methods Therefore, two split-plot experiments were carried out: with and without K supply. In both experiments,the treatments comprised a 3 x 4 factorial scheme. Treatments included three water regimes: 80% (no water deficit), 60% (moderate water deficit), and 40% (severe water deficit) of the soil's water retention capacity. Moreover, they comprised four doses of Si supplied via fertigation-0 kg/ha, 4 kg/ha, 8 kg/ha, and 12 kg/ha-arranged in a randomized block design with four replications.Results and discussion The appropriate dose of Si to be applied increased with the severity of the water deficit, with the recommended dose being 6 kg/ha, 7 kg/ha, and 8 kg/ha of Si for adequate water conditions, moderate water deficit, and severe water deficit, respectively.