Endogenous Hormones and Biochemical Changes during Flower Development and Florescence in the Buds and Leaves of Lycium ruthenicum Murr

Abstract

Lycium ruthenicum Murr. is one of the most important shrubs grown in northwest China. Healthy buds and leaves of L. ruthenicum Murr. were selected for the present study. Flower development was divided into six stages, namely, flower bud pre-differentiation (I), late flower differentiation (II), squaring stage (III), dew crown period (IV), open stage (V) and senescent stage (VI). Endogenous hormone content and specific value, soluble sugar, sucrose, starch, and soluble protein were measured, and ABA/IAA, ABA/GA3, ZR/IAA, ZR/GA3, and C/N were calculated in buds and leaves at stage VI. The results showed that ABA, GA3, and ZR content of buds significantly increased from flower bud pre-differentiation to late flower differentiation stage. However, ABA, GA3, and ZR content of leaves had the opposite change trend. From open stage to senescent stage, IAA, ABA, and GA3 content of buds and leaves significantly increased in L. ruthenicum Murr. However, ZR content of buds and leaves significantly decreased from open stage to senescent stage. ABA/IAA, ABA/GA3, ZR/IAA, and ZR/GA3 values of buds significantly increased from lower bud pre-differentiation to late flower differentiation stage. However, ABA/IAA, ABA/GA3, ZR/IAA, and ZR/GA3 values of leaves significantly decreased from lower bud pre-differentiation to late flower differentiation stage. ABA/IAA and ABA/GA3 of buds significantly increased from open stage to senescent stage, but ZR/IAA and ZR/GA3 of buds significantly decreased from open to senescent. At this stage, ABA/IAA, ABA/GA3, ZR/IAA, and ZR/GA3 significantly decreased in L. ruthenicum Murr. The higher soluble sugar and sucrose content in the buds and leaves were beneficial to the flower bud differentiation of L. ruthenicum. The increasing of soluble sugar improved the energy basis to florescence and senescent. The carbohydrates metabolism enhanced from open stage to senescent stage and nitrogen metabolism reduced from open stage to senescent stage of L. ruthenicum.