Photosynthesis of Cucumis sativus under weak light in response to different proportions of red to blue light
White 1ight ( contro1) , red 1ight, b1ue 1ight, red to b1ue at 7 : 1 and red to b1ue at 1 : 1 provided by 1ight-emitting diodes were app1ied to study the inf1uences of different combinations of red and b1ue 1ight on cucumber( Cucu-mis sativus) functiona1 1eaves under weak 1ight environment. Resu1ts showed that the stack of thy1akoid membranes of grown 1eaves under red 1ight was severe1y squeezed, and grana and stroma 1ame11ae were irregu1ar. The photochemica1 efficiency ( Fv/Fm ) , net photosynthetic rate ( Pn ) and stomata1 conductance ( Gs ) were the 1owest under red 1ight. Under b1ue 1ight, the SPAD va1ue and the deviation of excitation energy from fu11 ba1ance between PS1 and PS2 (β/α-1 ) were the 1owest. The specific 1eaf weight ( SLW) , PN , Gs , photosynthetic performance index ( PIcsm ) were the 1argest in red to b1ue 1ight at 1 : 1 treatment. A1though Pn in white 1ight treatment and red to b1ue 1ight at 7 : 1 treatment were significant1y greater than that under b1ue 1ight, there was no significant difference in Gs . Cucumber 1eaves grown under red 1ight a1one exhibited dys-functiona1 photosynthetic operation, and b1ue 1ight was indespensab1e for the efficient operation of cucumber photosynthetic apparatus under weak 1ight. Red to b1ue 1ight at 1 : 1, was favorab1e for the deve1opment of ch1orop1ast and high photosyn-thetic rate under weak 1ight.
1ight-emitting diodered and b1ue 1ight ratioCucumis sativusch1orop1ast u1trastructurephotosynthetic characteristic
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万方数据
维普
