Studies on effect of light treatments on growth and flowering in arugula (Eruca sativa)

Introduction

Arugula (Eruca sativa) is a leafy vegetable in the family Brassicaceae. It is an annual herbaceous plant distributed in the Mediterranean region. Arugula originated in the Mediterranean region and is known by its common names Rocket, True Rocket, Rocket Salad, Arugula, Roquette, or White Pepper (Gajra Garg and Vinay Sharma 2014) [3] . The name of this plant species is derived from the Latin word Eruca, which means a type of cabbage. The English The nutritional supply of arugula has been studied at different levels of qualitative and quantitative detail. In terms of macronutrients, ES leaves are a source of carbohydrate fibre, magnesium, calcium, and sodium, whereas the seeds are a source of fats, phosphorus, calcium, sodium, potassium, and magnesium. Arugula leaves are also rich in vitamins, including carotenes, tocopherols, vitamin C, and folic acid (Verhoeven et al., 1996) [10] . In general, whole arugula is a source of vitamins A, C, and K, as well as thiamine, riboflavin, niacin, vitamin B-6 (pyridoxine), and pantothenic acid (Innocenti et al., 2008) [5] . Arugula is commercially cultivated for its oil-bearing seeds and as a main crop under moisture-deficient and saline areas. It is not in great demand as an edible oil crop; hence, there is an obvious need to improve its oil quality so that it can find its place in the kitchen. Germplasm is the most valuable and essential raw material for crop improvement programs. Therefore, it is necessary to promote the use of this crop as a means to conserve its genetic diversity. Indoor farms represent a group of integrated technologies that can be configured in different ways for producing different crops. These crop types include leafy vegetables, herbs, tomatoes, flowers and microgreens (Wong et al.,2020) [11] . The structures used for production of the crops include greenhouses, high tunnels, buildings, or containers with artificial light sources (Choi et al., 2015) [2] . Research on indoor production has focused on factors such as light quality, light intensity, and photoperiod. Light is very vital for indoor production because of its impact on plant growth and yield. Light affects plant growth rate including stem thickness, branching,

Materials and Methods

The present investigation entitled "Studies on the Effect of Light Treatments on Growth and Flowering in Arugula (Eruca sativa L.)" was conducted during the year 2025-2026 at Urban Kisaan Private Limited, Gundlapochampally, Hyderabad, Telangana, India. The experiment was carried out under a controlled indoor cultivation system to evaluate the influence of different light spectra and photoperiods on the growth and flowering performance of arugula. Two arugula varieties, namely UKES and UKES, were subjected to varying combinations of red and blue LED light treatments under 16-hour and 18-hour photoperiods. The materials employed and the experimental procedures adopted for conducting the study are described in the following sections.

Experimental Design

The experiment was conducted using a Factorial Completely Randomized Design (FCRD) comprising ten treatment combinations replicated three times. Each treatment unit consisted of 30 arugula plants cultivated in a Nutrient Film Technique (NFT) hydroponic system. The plants were arranged in an alternating pattern to ensure uniform spacing and plant population throughout the experimental units. Sowing and transplanting operations were carried out during the second week of August, and all agronomic and crop management practices were maintained uniformly across treatments to minimize experimental variation. For data collection, ten plants from each treatment within every replication were selected at random and permanently tagged. Observations recorded from these representative plants were used to calculate treatment means for subsequent statistical analysis.

Reasons for Adopting Factorial Completely

Conclusion

The present study demonstrated that both light quality and photoperiod significantly influenced the vegetative growth of arugula under indoor cultivation conditions. Among the evaluated treatments, the 16-hour photoperiod combined with red and blue LED spectra consistently promoted superior growth compared with the 18-hour photoperiod and control treatment. The 2B:1R light combination under a 16-hour duration exhibited the highest overall performance in terms of plant height, leaf length, and leaf width, while the 2R:1B combination with the same photoperiod produced the greatest number of leaves. The control treatment consistently recorded the lowest values for all growth parameters. Although minor varietal differences were observed, both UKES and UKES responded positively to optimized LED lighting conditions. Overall, the findings indicate that a 16-hour photoperiod with an appropriate redto-blue light ratio is more effective for enhancing vegetative growth and improving crop performance in arugula cultivated under controlled indoor environments. These results provide useful guidance for the development of efficient lighting strategies in commercial indoor farming and controlled environment agriculture systems.

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