Genetic improvement of Chinese jujube for disease resistances: current status, knowledge gaps and research needs

Authors: SONG, LIHUA - Ningxia University; CAO, BING - Ningxia University; Meinhardt, Lyndel; Bailey, Bryan; Zhang, Dapeng

Submitted to: Crop Breeding, Genetics and Genomics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/26/2019
Publication Date: 9/2/2019
Citation: Song, L., Cao, B., Meinhardt, L.W., Bailey, B.A., Zhang, D. 2019. Genetic improvement of Chinese jujube for disease resistances: current status, knowledge gaps and research needs. Crop Breeding, Genetics and Genomics. 2019;1:e190015. https://doi.org/10.20900/cbgg20190015.
DOI: https://doi.org/10.20900/cbgg20190015

Interpretive Summary: Chinese jujube (Ziziphus jujuba Mill.) is a fruit tree that has an outstanding adaptability to marginal lands and produces in a broad range of climate conditions. This fruit is economically important in Asia and due to it wide production capacity it is a potential new crop in the United States, especially in the Southwest. In this study diseases management, and jujube breeding limitations are evaluated and future research needs are discussed with a focus on developing disease resistant cultivars of Chinese jujube. This information will be used by plant breeders, germplasm curators, extension specialist and ultimately jujube producers to improve the utilization and productivity of this tree crop.

Technical Abstract: Chinese jujube (Ziziphus jujuba Mill.) is one of the earliest domesticated fruit trees in the world. This fruit crop is becoming increasingly popular globally for its outstanding adaptability to marginal land and broad range of climate conditions. There is a growing demand by growers and consumers of new cultivars with improved yield, earliness, resistance to biotic and abiotic stresses and fruit quality attributes. Despite the consensus that disease is the top-ranking production constraint and growing disease resistant cultivars is the most sustainable and cost-effective approach for diseases management, breeding jujube for disease resistance is still in its infant stage. Several major knowledge gaps remain to be filled in the current breeding scheme for enhancing disease resistance. These knowledge gaps include, but not limit to 1) lack of clear understanding about the enemy pathogens in terms of their taxonomy, epidemiology and genetic diversity; 2) lack of standardized screening methods to identify host resistance; 3) high rate of germplasm mislabeling and 4) ineffective production of hybrid progenies. Nonetheless, recent progress in utilization of male sterile parent in controlled crosses, coupled with mounting genomic information on both enemy pathogens and jujube tree, will likely speed up the introgression of host resistance into desirable parental clones. This paper summarizes the status and suggests future research needs for developing disease resistant cultivars of Chinese jujube. Although the review focuses on jujube breeding programs in China, the summarized information should be useful to researchers in international jujube community as well.