Effects of exogenous growth regulator treatment on floral initiation of pear progenies from hybrids 'Mantianhong' x 'Dangshansuli'.

[Objectives] This study aims at exploring the effects of growth regulators on floral differentiation, expression of flowering related genes and nutrient accumulation of pear hybirds. [ Methods] This study took 'Mantianhong' x 'Dangshansuli' progenies as materials, and all the individuals were five years old but still have no flower. We sprayed the 6-BA and ethephon( Eth) (100 mg·kg-1 6-BA, 100 mg · kg-1 Eth, 100mg ·kg-1 6-BA+1 00 mg · kg-1 Eth) with water control during the period of flower bud differentiation. [Results] All different growth regulator treatments can facilitate the florescence of the progenies. The mixed 6-BA and ethephon treatment increased the most flower buds among three treatments. All treatments promoted the expression of FLOWERING LOCUS T( FT) and LEAFY(LFY) genes during floral bud differentiation, and inhibited the expression of TERMINAL FLOWER 1(TFL1) gene; the treatments enhanced the content of ZT and ABA, reduced the hormone content of GA3 and IAA, and improved the content of starch and the ratio of C/N in floral buds. [Conclusions] The synthesis analysis revealed that gene expression, endogenous hormone and nutriment influenced each other, and they regulated floral initiation of hybrid progenies together. [ABSTRACT FROM AUTHOR]