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Adding green [G (500–600 nm)] radiation to blue [B (400–500 nm)] and red [R (600–700 nm)] radiation creates white radiation and improves crop inspection at indoor farms. Although G radiation can drive photosynthesis and elicit the shade-avoidance response, its effects on plant growth and morphology have been inconsistent. We postulated G radiation would counter the suppression of crop growth and promotion of secondary metabolism by B radiation depending on the B photon flux density (PFD). Lettuce (Lactuca sativa ‘Rouxai’) was grown in a growth room under nine sole-source light-emitting diode (LED) treatments with a 20-hour photoperiod or in a greenhouse. At the same photosynthetic photon flux density [PPFD (400–700 nm)] of 180 μmol·m−2·s−1, plants were grown under warm-white LEDs or increasing B PFDs at 0, 20, 60, and 100 μmol·m−2·s−1 with or without substituting the remaining R radiation with 60 μmol·m−2·s−1 of G radiation. Biomass and leaf expansion were negatively correlated with the B PFD with or without G radiation. For example, increasing the B PFD decreased fresh and dry mass by up to 63% and 54%, respectively. The inclusion of G radiation did not affect shoot dry mass at 0 or 20 μmol·m−2·s−1 of B radiation, but it decreased it at 60 or 100 μmol·m−2·s−1 of B radiation. Results suggest that the shade-avoidance response is strongly elicited by low B radiation and repressed by high B radiation, rendering G radiation ineffective at controlling morphology. Moreover, substituting R radiation with G radiation likely reduced the quantum yield. Otherwise, G radiation barely influenced morphology, foliage coloration, essential nutrients, or sensory attributes regardless of the B PFD. Increasing the B PFD increased red foliage coloration and the concentrations of several macronutrients (e.g., nitrogen and magnesium) and micronutrients (e.g., zinc and copper). Consumers preferred plants grown under sole-source lighting over those grown in the greenhouse, which were more bitter and less acceptable, flavorful, and sweet. We concluded that lettuce phenotypes are primarily controlled by B radiation and that G radiation maintains or suppresses lettuce growth depending on the B PFD.

O objetivo geral deste trabalho foi analisar o efeito da radiação vermelha de baixa intensidade sobre alguns parâmetros cinéticos do espermatozoide canino criopreservado. Ejaculados de oito cães adultos foram centrifugados, rediluídos em meio tris-gema de ovo com 6% de glicerol, e, posteriormente, fracionados em: T1: incidência de radiação vermelha (660 NM) (Fisioled - Mmoptics - 100mW) por 60 segundos, antes do resfriamento e após a descongelação; T2: incidência somente antes do resfriamento; T3: incidência somente após a descongelação; e T4: sem incidência. Após a descongelação, as amostras foram submetidas ao TTR utilizando-se Sperm Class Analyzer(r). No TTR0, TTR60 e TTR90, não houve diferença entre as variáveis analisadas pelo CASA. Somente no TTR30 os efeitos da incidência da radiação vermelha foram evidentes e significativos em T1 e T2; T1 resultou em baixa MT (12,5 + 10,6%) e T2 determinou o melhor resultado de MT 40,3 + 26,1%. De forma similar T1 apresentou maior número de espermatozoides estáticos (77,5±28,9%) em relação ao T2 (50,6±28%). Concluiu-se que a dupla incidência de radiação vermelha de baixa intensidade antes do resfriamento e após a descongelação teve efeito deletério sobre a motilidade do espermatozoide canino, expressa principalmente aos 30 minutos após descongelação. The aim of this study was to analyze the effect of low intensity red light on some kinetic parameters of cryopreserved canine sperm. Ejaculates from 08 adult dogs were centrifuged, diluted in Tris-egg yolk with 6% glycerol, and subsequently separated into: T1: incidence of red light (660 nm) (Fisioled -MMOptics - 100mW) for 60 seconds before the cooling and after thawing, T2: just before cooling, T3: only after thawing, and T4: no incidence. After thawing the samples were subjected to TTR using Sperm analyzer(r). In TTR0, TTR60 and TTR90 there were no differences between the variables analyzed by CASA. Only in TTR30 the effects of the incidence of red light were visible and significant in T1 and T2. T1 resulted in low MT (12.5 ±10.6%) and T2 determined the best result of MT 26.1%±40.3. Similarly T1 showed a higher number of static spermatozoa (77.5±28.9%) compared to T2 (50.6±28%). We concluded that the double incidence of low intensity red light, before cooling and after thawing, had a deleterious effect on canine sperm motility expressed at 30 minutes after thawing.