18402
Two papers now show how the interplay between brassinosteroid phytohormones and frontier genes contributes to boundary formation in plants .
 Chemical: brassinosteroid
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: brassinosteroid 
Answer:
 Chemical: brassinosteroid