Role Of SlPIN1,SlPIN3 And SlPIN4 In Abscission Of Tomato Pedicel

Tomato(Solanum lycopersicum)is one of the most important vegetable economic crops.Falling and falling is one of the main factors restricting its economic benefits.Understanding the mechanism of tomato organ shedding and formulating measures to prevent flowering and fruit falling have important implications for basic agricultural research,applied research,and actual agricultural production.PIN-FORMED is the main auxin output protein.The correct spatio-temporal expression pattern can form a suitable auxin gradient to guide organ development.However,the specific function of SlPIN is not clear during organ shedding.Based on the SlPIN1,SlPIN3,and SlPIN4 genes that were specifically expressed in the tomato region of this study,the SlPIN-silenced plants were constructed using the VIGS test method.The silencing efficiency was verified by real-time fluorescence quantification.The investigation of the shedding rate of the combined silenced plants and control plants,GUS staining and the change of the auxin flow rate in the isolated area preliminarily confirmed the key role of the specific region-specific proteins SlPIN1,SlPIN3 and SlPIN4 in the shedding process.The main results were:1.The pTRV-SlPIN1,pTRV-SlPIN3 and pTRV-SlPIN4 silencing vectors were constructed and three silencing plants were obtained by infecting tomato seedlings with Agrobacterium GV3101.The silenced plants with higher silencing efficiency were identified by qRT-PCR.2.qRT-PCR results showed that when SlPIN1,SlPIN3,and SlPIN4 were silenced,the expression of the remaining SlPINs was not affected,indicating that we obtained specifically silenced SlPIN1,SlPIN3,and SlPIN4 plants.3.Silenced Sl PIN1,SlPIN4 plants significantly accelerated shedding;IAA pretreatment silenced SlPIN1,and the shedding rate of SlPIN4 plants was significantly lower than that of the control plants.However,there was no significant difference in the shedding rate of silencing SlPIN3 plants with control plants.4.GUS staining and IAA flow rate measurement in the isolated area indicated that decreasing the expression of SlPIN1 and SlPIN4 resulted in the accumulation of auxin in the basal ovary and the decrease of auxin content and flow velocity in the detached region of the ovary,thereby accelerating the detachment of the pedicel.The results showed that SlPIN1 and SlPIN4 play an important role in mediating auxin in the source-sink transport of plants.