I have an appointment of research and extension in nutrition and stress physiology of deciduous fruit crops with emphasis on apple. The goal of my research program is to better understand the physiological processes underlying carbon/mineral nutrition and environmental stresses on tree growth and fruiting, and develop management practices for improving orchard productivity and fruit quality. I am also involved in undergraduate and graduate teaching.
All pome and stone fruits of the Rosaceae family, such as apple, pear, peach and cherry, synthesize, transport, and utilize both sorbitol and sucrose, with sorbitol being predominant. This contrasts with most other plants where sucrose is the only sugar translocated from source leaves to sink organs. The presence of sorbitol in these tree fruits raises an interesting question as to its role in carbohydrate metabolism, tree growth and development, and stress tolerance. We are taking physiological, biochemical and molecular approaches to understand the function of sorbitol as both a carbon substrate and a signaling molecule in apple. We are also very interested in malate metabolism and accumulation in addition to carbohydrates during apple fruit growth and development as well as their responses to nutrient stress and other environmental stresses in the context of fruit quality improvement. On the more applied side, our research addresses uptake, translocation, and utilization, and demand-supply relationship of nitrogen, calcium, and potassium in apple trees to provide basis for optimizing nutrient inputs into yield- and labor-efficient high density apple orchards.
Outreach and Extension Focus
The goal of my extension program is to effectively deliver research-based, up to date information and provide expertise concerning nutrient management to the apple industry in New York and beyond through collaborations with faculty, extension educators, and growers. My extension activities are closely tied with my applied research. The current focus is management of nitrogen, potassium, calcium and other essential nutrients to improve yield and quality of high density apple orchards.
My goal in teaching and advising is to train students so that they develop to realize their academic potential, resulting in not only getting a degree from Cornell, but more importantly becoming a “thinker” and a “doer” in the field of horticultural sciences.
My teaching has been largely in mineral nutrition of fruit crops and advanced analytical techniques in plant science.
- Meng, D., He, M., Bai, Y., Xu, H., Dandekar, A. M., Fei, Z., & Cheng, L. (2018). Decreased sorbitol synthesis leads to abnormal stamen development and reduced pollen tube growth via an MYB transcription factor, MdMYB39L, in apple (Malus domestica). New Phytologist. 217:641-656.
- Meng, D., Li, C., Park, H., González, J., Wang, J., Turgeon, G. B., & Cheng, L. (2018). Sorbitol modulates resistance to Alternaria alternata by regulating the expression of an NLR resistance gene in apple. Plant Cell. 30:1562-1581.
- Duan, N., Bai, Y., Sun, H., Wang, N., Ma, Y., Li, M., Wang, X., Jiao, C., Legall, N., Mao, L., Wan, S., Wang, K., He, T., Feng, S., Zhang, Z., Mao, Z., Shen, X., Chen, X., Jiang, Y., Wu, S., Yin, C., Ge, S., Yang, L., Jiang, S., Xu, H., Liu, J., Wang, D., Qu, C., Wang, Y., Zuo, W., Xiang, L., Liu, C., Zhang, D., Gao, Y., Xu, Y., Xu, K., Chao, T., Fazio, G., Shu, H., Zhong, G., Cheng, L., Fei, Z., & Chen, X. (2017). Genome re-sequencing reveals the history of apple and supports a two-stage model for fruit enlargement. Nature Communications. 8:11.
- Li, M., Li, D., Feng, F., Zhang, S., Ma, F., & Cheng, L. (2016). Proteomic analysis reveals dynamic regulation of fruit development and sugar and acid accumulation in apple. JXB: Journal of Experimental Botany. 67:5145-5157.
- Wu, T., Wang, Y., Zheng, Y., Fei, Z., Dandekar, A., Xu, K., Han, Z., & Cheng, L. (2015). Suppressing sorbitol synthesis substantially alters the global expression profile of stress response genes in apple (Malus domestica) leaves. Plant Cell Physiology.
- Li, P., Zhang, Y., Einhorn, T. C., & Cheng, L. (2014). Comparison of phenolic metabolism and primary metabolism between green 'Anjou' pear and its bud mutation, red 'Anjou'. Physiologia Plantarum. 150:339-354.
- Feng, F., Li, M., Ma, F., & Cheng, L. (2013). Phenylpropanoid metabolites and expression of key genes involved in anthocyanin biosynthesis in the shaded peel of apple fruit in response to sun exposure. Plant Physiology and Biochemistry. 69:54-61.
- Bai, Y., Dougherty , L., Li, M., Fazio, G., Cheng, L., & Xu, K. (2012). A natural mutation-led truncation in one of the two aluminum-activated malate transporter-like genes at the Ma locus is associated with low fruit acidity in apple. Molecular Genetics and Genomics. 287:663-678.
- Li, M., Feng, F., & Cheng, L. (2012). Expression patterns of genes involved in sugar metabolism and accumulation during apple fruit development. PLOS One. 7:e33055.
- Fu, Q., Cheng, L., Guo, Y., & Turgeon, E. G. (2011). Phloem loading strategies and water relations in trees and herbaceous plants. Plant Physiology. 157:1518-1527.