Growth & Development

Co-application of biochar and nitrogen stimulates growth of pecan seedlings

How does combined biochar and nitrogen fertiliser application influence the growth of pecan seedlings?

Biochar, a soil modifier derived from high-temperature treatment of crop stalks, dead branches and other biomass has been widely used to improve soil health and promote plant growth. Several studies have shown that application of biochar can aerate compact soil, decrease soil bulk density and revamp soil microbial communities. In addition to its high carbon content (>60 % carbon), biochar is rich in nutrients such as calcium, potassium, magnesium, nitrogen and phosphorus and can be used to improve soil fertility, promote root growth and nutrient absorption and increase plant biomass and yield. Biochar also influences soil nitrogen transformations and has been shown to reduce N2O emissions by influencing nitrification rates. This presents biochar application as a means to reduce the adverse environmental impacts caused by overuse of commercial fertilizer. However, studies of the benefits of biochar amendment with simulated nitrogen deposition have mainly focused on agricultural crops, such as corn and rice, while study of tree species’ growth is still lacking

The pecan nuts of Pawnee cultivar on the tree. The nuts are maturing and will soon ready for harvesting. Image credit: K. Lim.

In their new study published in AoBP, Hou et al. investigated the effect of combining biochar amendment and simulated nitrogen deposition on the growth of pecan seedlings at varying doses. Under the combined treatment of a low level of biochar amendment and a high level of stimulated nitrogen deposition, the seedlings’ height, photosynthetic rate and total chlorophyll content improved the most compared with biochar treatment alone. Biochar amendment alleviated the antagonist effect from simulated nitrogen deposition that suppressed the absorption of phosphorus, potassium, and iron. Applying both biochar amendment and simulated nitrogen deposition to the growth of seedlings was additive. The agronomic management of pecan plantations requires careful planning of fertilizer application, which is performed according to the developmental phases of pecan plants. The present work could serve as an important basis for fertilizer management, which could incorporate the application of biochar with N application, thereby reducing the use of fertilizer in the field.

Researcher highlight

Kean-Jin Lim (left) and Zhengjia Wang (right)

Kean-Jin Lim grew up in Malaysia. He started work as a researcher in Finland in 2006 and earned his PhD in Biotechnology at the University of Helsinki in 2017. Kean-Jin moved to Hangzhou, China in late 2018. He is currently an Associate Professor at Zhejiang A&F University and works in Zhengjia Wang’s group. He is interested in bioinformatics, plant (forest) genetics and functional genomics.

Zhengjia Wang grew up in China. He graduated from Beijing Forestry University in 2006 with a doctorate in Biochemistry and Molecular Biology. He conducted his postdoctoral training at Pennsylvania State University in 2008. Zhengjia is now a Professor at Zhejiang A&F University and leader of the pecan (hickory) research group. As a talented young researcher, he won several youth awards from the Zhejiang Provincial Government. He is interested in economic forest genetic breeding and plants developmental biology.

The research team focuses on pecan (hickory) flowers, fruits/nuts and plants development. The group uses molecular biology, bioinformatics, biochemistry and next-generation sequencing approaches to extract and investigate genes or pathways that can improve breeding quality.