Respon Pertumbuhan dan Hasil pada Tanaman Bayam (Amaranthus sp) terhadap Biofortifikasi Unsur Hara Kalsium (Ca) dan Besi (Fe) dengan Sistem Hidroponik DFT (Deep Flow Technique)

Hasmeda M, Sari IY, Munandar M, Ammar M, Gustiar F. 2021. Growth response and yield of spinach (Amaranthus sp) on biofortification of calsium (Ca) and iron (Fe) with DFT (Deep Flow Technique) system. In: Herlinda S et al. (Eds.), Prosiding Seminar Nasional Lahan Suboptimal ke-9 Tahun 2021, Palembang 20 Oktober 2021. pp. 721-733. Palembang: Penerbit & Percetakan Universitas Sriwijaya (UNSRI).This research was conducted to know the dose of calcium (Ca) and Ferro (Fe) which were the best factor in the increase of plant nutrient which did not disturb the growth and production of Amaranthus sp. by using hydroponic DFT (Deep Flow Technique). This research was conducted at Hydroponic laboratory Agronomy study program Faculty of Agriculture Sriwijaya University which was conducted from November 2020 until April 2021. This research used Amaranthus seed brand “Panah Merah”. The Randomized Block Design with 8 treatments and three replications were used. They were: CFo = AB, C1=200 ppm, C2=400 ppm C3-600 ppm, F1=5 ppm, F2=7.5 ppm and F3=10 ppm. Diversity Analysis used ANOVA and BNT 5%. Parameters being observed were plant height (cm), Number of leaves, leaves greenest level, leaf area (cm2), root volume (ml3), fresh plant weight (g), dry plant weight (g), Calcium concentration (Ca) and Fe concentration in leaves. Research results showed that the increases of Ca and Fe concentration occurred along with the increase of hydroponic solution. The increase of Ca 600 ppm did not inhibit plant growth and the increase of Fe 5 ppm was the maximum concentration which not inhibit the growth of Amaranthus and gave good impacts and optimal plant growth

"Adaptive response" - some underlying mechanisms and open questions

Organisms are affected by different DNA damaging agents naturally present in the environment or released as a result of human activity. Many defense mechanisms have evolved in organisms to minimize genotoxic damage. One of them is induced radioresistance or adaptive response. The adaptive response could be considered as a nonspecific phenomenon in which exposure to minimal stress could result in increased resistance to higher levels of the same or to other types of stress some hours later. A better understanding of the molecular mechanism underlying the adaptive response may lead to an improvement of cancer treatment, risk assessment and risk management strategies, radiation protection, e. g. of astronauts during long-term space flights. In this mini-review we discuss some open questions and the probable underlying mechanisms involved in adaptive response: the transcription of many genes and the activation of numerous signaling pathways that trigger cell defenses - DNA repair systems, induction of proteins synthesis, enhanced detoxification of free radicals and antioxidant production.Publisher PDFPeer reviewe