Photosynthetic apparatus performance of tomato seedlings grown under various combinations of LED illumination

Abstract

It is already known that the process of photosynthesis depends on the quality and intensity of light. However, the influence of the new light sources recently used in horticulture, known as Light Emitting Diodes (LEDs), on this process is not yet fully understood. Chlorophyll a fluorescence measurement has been widely used as a rapid, reliable, and noninvasive tool to study the efficiency of the photosystem II (PSII) and to evaluate plant responses to various environmental factors, including light intensity and quality. In this work, we tested the responses of the tomato photosynthetic apparatus to different light spectral qualities. Our results showed that the best performance of the photosynthetic apparatus was observed under a mixture of red and blue light (R7:B3) or a mixture of red, green and blue light (R3:G2:B5). This was demonstrated by the increase in the effective photochemical quantum yield of PSII (Y[II]), photochemical quenching (qP) and electron transport rate (ETR). On the other hand, the mixture of red and blue light with a high proportion of blue light led to an increase in non-photochemical quenching (NPQ). Our results can be used to improve the production of tomato plants under artificial light conditions. However, since we found that the responses of the photosynthetic apparatus of tomato plants to a particular light regime were cultivar-dependent and there was a weak correlation between the growth and photosynthetic parameters tested in this work, special attention should be paid in future research.

Photosynthetic performance of rocket (Eruca sativa. Mill.) grown under different regimes of light intensity, quality, and photoperiod

“…The results showed that after plants dark-acclimation the best light mode that squandered excess lowering energy were LM2 and CK ( Fig 6A ), whereas the best treatment squandered excess lowering energy was LM2 after light-acclimation ( Fig 6B ). The results obtained differed from those reported previously other researches [ 16 , 50 – 52 ], where it was reported that the mixture of red and blue light with a high ratio of red to blue led to an increase of Y(II)max (Fv/Fm).…”

Light quality and quantity affect graft union formation of tomato plants

“…The LED lamps (UH-BLDT0510) used in this study were manufactured by Kedao Technology Corporation (Huizhou, China). Tomato seeds were planted 30 days before grafting under 100 μmol m −2 s −1 R7:B3 (red ~ 70: blue ~ 30), which was chosen as the best LED source in our previous research 54 , 55 . The seeds were sown in trays (W 28 cm × L 54 cm × H 5 cm, Luoxi Plastic Products Co., Shandong, China) filled with the commercial growing substrate (N 1 :P :1 K 1 ≥ 3%, Organic matter ≥ 45%, pH 5.5–6.5, Jiangping Enterprise Co., Fujian, China).…”

Color-Specific Recovery to Extreme High-Light Stress in Plants

“…The NPQ for BLT was three-fold higher on Day-0 when compared to the RLT values. It is important to note that the NPQ measurements reported here were taken during a small period of time in the induction phase, and therefore the values should be compared to early data points of NPQ curves found in the literature [ 40 ] (i.e., a compilation of NPQ curves recorded from tomato plants). Still, the NPQ values obtained from in the control plants were lower than numbers reported in the literature and should be taken with caution.…”