Jianjun Chen

By Jianjun Chen and Xiangying Wei

Container-grown plants refer to plants produced in confined volume filled with substrates. The substrates endogenously have limited nutrients and low water-holding capacity. Plants grown in the containers must be fertilized and watered frequently varying from daily to weekly. Frequent fertilization and irrigation can result in nutrient leaching and/or runoff. Since nitrogen (N) is a key component of the majority of fertilizers, container plant production has been viewed as a source of N leaching and/or runoff. The leaching and runoff, if in large quantities on a year-round basis, could affect surface and ground water quality. Application of controlled-release fertilizers (CRFs) has been reported to have less N leaching than plants fertilized with water-soluble fertilizers (WSFs). However, there are different types of CRFs with different compositions and longevities on the market. Container plants also differ greatly in their growth and development and in N requirement. Thus, production of high-quality container plants with minimum N leaching using CRFs still remains challenging. This article is intended to discuss characteristics of container plant production and N leaching and runoff during production, and to document that CRF application can reduce N leaching and/or runoff. Certain requirements for future development of CRFs are also discussed.

Part of the book: Nitrogen in Agriculture

By Jianjun Chen, ChihCheng T. Chao and Xiangying Wei

Goji, gojiberry, or wolfberry is the fruit of Lycium barbarum L., L. chinense Mill., or L. ruthenicum Murr. in the family Solanaceae Juss. The fruit is bright orange-red or black and is edible with a sweet and tangy flavor. Gojiberry is rich in polysaccharides, flavonoids, carotenoids, betaine, kukoamine A, sitosterol, and other compounds which have antioxidant, anti-inflammatory, and anti-neoplastic properties and have been used for the treatment of various blood circulation disorders and diabetes. Recently, there is an increased demand for high-quality gojiberry and its products because they are considered a superfruit. China is the main producer and supplier of gojiberry in the world. Thus far, limited information is available about genetic resources, breeding activities, and major cultivars of gojiberry. This chapter is intended to review the current knowledge on gojiberry germplasm resources and their relationships as well as to describe gojiberry breeding activities. Future prospects on gojiberry cultivar development are also discussed.

Part of the book: Breeding and Health Benefits of Fruit and Nut Crops