Plant materials and growth conditions
Arabidopsis thaliana plants were grown in greenhouse at 21°C and 16h- light/8h-dark photoperiod. T-DNA insertion mutant of kcs7(At1g71160, SALK_023400), kcs15 (At3g52160, SALK_209946C) andkcs21 (At5g49070, SALK_089611) in Col-0 background were all obtained from the ABRC stocks. T-DNA insertion status of KCS7 ,KCS15 and KCS21 were confirmed using the T-DNA border primer SALK LBb1.3 in combination with gene-specific primers listed in Table S1.