Plant material and growth conditions
Arabidopsis thalianaaccessions Col-0 was as wild-type plant genotypes. The marker linespDR5:GUS (Ulmasov, Murfett, Hagen, & Guilfoyle, 1997),pDR5:Lucifease(Moreno-Risueno et al., 2010), pCYCB1:GUS (Himanen et al., 2002),PIN1:PIN1:GFP (Benkova et al., 2003), PIN2:PIN2:GFP(Blilou et al., 2005), PIN3:PIN3:GFP (Zadnikova et al., 2010),PIN7:PIN7:GFP (Blilou et al., 2005) and the mutant linestir1afb2 (Dharmasiri, Dharmasiri, & Estelle, 2005),CASP1pro:shy2-2 (J. E. M. Vermeer et al., 2014),slr-1/iaa14 (Fukaki, Tameda, Masuda, & Tasaka, 2002),arf7arf19 (Yoko Okushima, Fukaki, Onoda, Theologis, & Tasaka,
2007), aux1-7 (Pickett, Wilson, & Estelle, 1990), pin2(Roman, Lubarsky, Kieber, Rothenberg, & Ecker, 1995), pin3(salk_005544 ), ech2ibr1ibr3ibr10 (Strader et al., 2011),
and gh3.3-1gh3.5-2gh3.6-1 (Gutierrez et al., 2012) were used in
this study. After 2-3 d of stratification at 4°C in the dark,Arabidopsis seeds were surface‐sterilized with 30% (v/v) NaClO
solution for 10 min. The seeds were germinated and grown on agar plates
containing Murashige and Skoog Basal Salts Mixture (MS salts, PhytoTech
LABS) in square Petri plates (10 ×10 cm). Standard growth medium
consisted of 0.5 × MS salts (2.15 g l-1), 0.1g
l-1 Myo-inositol, 0.5g l-12-(N-morpholino) ethanesulfonic acid (MES), 1% sucrose (pH 5.7), and
1% Agar (Solarbio). Plants were vertically placed in a plant growth
chamber, under a long-day photoperiod (16 h: 8 h, light: dark), with a
light intensity of 100 μmol m-2 s-1,
at 22 °C. After 3 d of growth, the seedlings were applied for further
experiments.