PENGARUH SPEKTRUM CAHAYA TERHADAP PERTUMBUHAN, HASIL, DAN KUALITAS DUA KULTIVAR CABAI MERAH (Capsicum annuum L.) DI RUMAH KACA

Abstract

Cahaya merupakan salah satu faktor lingkungan yang memengaruhi proses fisiologis tanaman, termasuk fotosintesis, respirasi, dan sintesis senyawa bioaktif. Cabai merah (Capsicum annuum L.) merupakan komoditas hortikultura bernilai ekonomi tinggi yang memerlukan kondisi lingkungan optimal, termasuk pencahayaan yang tepat guna mendukung pertumbuhan dan hasil maksimal. Penelitian ini bertujuan memperoleh informasi mengenai pengaruh spektrum cahaya terhadap pertumbuhan, hasil, dan kualitas dua kultivar cabai merah. Penelitian dilaksanakan di rumah kaca menggunakan Rancangan Kelompok Lengkap Teracak, dengan dua faktor yaitu spektrum cahaya (tanpa lampu (indoor), putih, ungu, ungu putih dan cahaya matahari (outdoor)) serta varietas (Tangguh F1 dan Arisa IPB). Parameter yang diamati meliputi aspek agronomi, hasil panen, serta kualitas biokimia tanaman. Penelitian ini menunjukkan perlakuan lampu ungu putih memberikan hasil terbaik pada bobot buah per tanaman sebesar 105,19 g, lampu putih mempercepat umur berbunga (5,30 MST). Perlakuan cahaya matahari (outdoor) menghasilkan kandungan capsaicin tertinggi (26,19 mg g-1) disertai aktivitas antioksidan tertinggi (24,28%). Varietas Arisa IPB menunjukkan kualitas lebih baik terutama pada kandungan kalium, fosfor, dan aktivitas antioksidan. Pengaturan spektrum cahaya dan pemilihan varietas yang tepat dapat meningkatkan produktivitas dan kualitas cabai merah secara optimal.

Light is one of the environmental factors influencing plant physiological processes, including photosynthesis, respiration, and the synthesis of bioactive compounds. Red chili (Capsicum annuum L.) is a horticultural commodity with high economic value that requires optimal environmental conditions, including appropriate lighting, to support maximum growth and yield. This study aimed to investigate the effects of light spectrum on the growth, yield, and quality of two red chili cultivars. The experiment was conducted in a greenhouse using a Randomized Complete Block Design with two factors: light spectrum (no lamp/indoor, white, purple, purple-white, and sunlight/outdoor) and cultivar (Tangguh F1 and Arisa IPB). Observed variables included agronomic traits, yield components, and biochemical quality. Results showed that purple-white light treatment produced the highest fruit weight per plant (105.19 g), while white light accelerated flowering time (5.30 weeks after planting). The sunlight (outdoor) treatment resulted in the highest capsaicin content (26,19 mg g-1) accompanied by the highest antioxidant activity (24.28%). The Arisa IPB variety exhibited a better quality, particularly in potassium and phosphorus content, as well as antioxidant activity. Proper adjustment of light spectrum and cultivar selection can enhance the productivity and quality of red chili peppers optimally.