Asian Journal of Plant and Soil Sciences

Plant factory offers a logical solution for sustainable food production. However, it provokes high energy and cost due to the use of artificial lighting. In this regard light quality strongly impairs growth and quality of plants due to inhibition of thylakoid multiprotein complex and photosynthetic metabolism under lighting environment. The molecular mechanism behind this phenomenon is still unclear. The objective of this research was to examine first comparative quantitative proteomic analysis of lettuce under light quality in the closed biological production system. We investigated response of lettuce proteome under three light treatments (R:B ratio of 1.2 and 2.2 provided by LEDs, and R:B ratio of 1.8 provided by the fluorescent lamp). The rapid identification and sensitive detection in protein expression in response to light quality were measured by mass spectrometry and bioinformatics followed by Mascot database used in this study. Our results demonstrated that light quality had significant effect on altering the proteomic level and expression pattern in lettuce leaves, in addition light quality had marked striking effect on functional, molecular and biological level among light treatments. The study successfully identified seventy-one proteins for lettuce plants treated with fluorescent lamps, fifty and forty-one for LEDs, respectively, which were involved in energy metabolism and regulation of morphogenesis. The results observed dramatically altered molecular mechanism of key enzymes in thylakoid complex proteins and photosynthetic metabolism among light treatments due to effect of spectral light quality difference. Importantly, the lettuce plants have lower expression of proteins diagnostic for LEDs light. In this regard our data will provide foundation for future detail study to unlock the advantages of this next generation lighting technology to strengthen the connection between light quality and multi complex protein (CB23_HORVU) of LHC family in highly energy-efficient horticulture.

Hydrocarbon contaminated soil is a global problem. In Mexico, the regulations for environmental protection do not include any bioindicators to evaluate toxic effects in microorganisms and plants caused by hydrocarbons. The jamaica plant (Hibiscus sabdariffa L.) has a percentage of germination that is greater than 90%, and nascence occurs between 2 to 3 days. Thus, the objective was to verify whether the jamaica plant would be a viable bioindicator of toxicity in soil contaminated by hydrocarbons. In the toxicity bioassay, three hydrocarbon concentrations were tested: 895 ppm (T1), 447 ppm (T2), 223 ppm (T3) and a control without hydrocarbon (C), for two soils at the coast of Oaxaca, México (Bajos de Coyula and Barra de la Cruz). The germination index (GI) that integrates the relative percentage of germination (RPG) and the relative root growth (RRG) was determined. The following relationship was obtained: lower value at higher hydrocarbon concentration, in the indices that were tested. Inhibition in seedling height was lower than in root growth; while in the root growth up to 73.4% was inhibited, in the seedling height only 6% (T3) and 48% (T1) were inhibited. GI mean in Barra de la Cruz (43.7) was 1.1 times greater compared to Bajos de Coyula (39.3). Partial reduction of oxygen and lack of moisture in the soil matrix could be the possible causes of the negative effect on germination due to hydrocarbon. GI of the jamaica, was negatively affected by the hydrocarbon in soil, but, germination was not completely inhibited. Based on these observations, we suggest that the jamaica plant (Hibiscus sabdariffa L.) can be used as a bioindicator of toxicity in hydrocarbon contaminated soil.