2019 4th International Conference on Agricultural Science and Biotechnology (ICASBIO2019) (http://www.icasbio.org/2019/en/home) is a platform for academic communications between specialists and scholars in the fields related to agricultural science and biotechnology. ICASBIO2019 will be held in Nanjing, China during Aug. 12-14, 2019. Nanjing is the capital of Jiangsu province and the second largest city in eastern China (after Shanghai). Publication 2019 4th International Conference on Agricultural Science and Biotechnology (ICASBIO2019) accepts original and unpublished papers. Both Full paper and Abstract are welcomed. Full papers accepted by the conference will be published online in the following journals of Science Publishing Group (http://www.sciencepublishinggroup.com). The journals have been indexed and abstracted by WorldCat, CrossRef, Electronic Journals Library, CNKI, Zeitschriftendatenbank, EZB, ResearchBib, Polish Scholarly Bibliography, Wissenschaftszentrum Berlin, etc. Agriculture, Forestry and Fisheries (AFF) http://www.sciencepublishinggroup.com/j/aff ISSN Print: 2328-563X ISSN Online: 2328-5648 American Journal of BioScience (AJBIO) http://www.sciencepublishinggroup.com/j/ajbio ISSN Print: 2330-0159 ISSN Online: 2330-0167 Science Discovery (SD) http://www.sciencepublishinggroup.com/j/sd ISSN Print: 2331-0642 ISSN Online: 2331-0650