Kultur In Vitro Kalus dengan Perlakuan Chromium terhadap Tingkat Embriogenesis dan Respon Gen Enzim Antioksidan pada Tanaman Padi (Oryza sativa L.)

Abstract

Chromium is one of the active heavy metal compounds that are released excessively in the environment due to the impact of industrialization. Chromium has phytotoxic effects by inhibiting germination and even electrolyte leakage in plant cells. Plants have a defense system by activating genes encoding resistance traits, namely antioxidant enzyme genes. Antioxidant enzyme genes can reduce Reactive Oxygen Species (ROS) compounds that are produced excessively due to abiotic stress. Indonesian local rice needs to be studied further to determine the level of tolerance to abiotic stress, especially on heavy metals. This study aims to determine the effect of chromium on 10 local Indonesian rice varieties both in vivo and in vitro and determine the antioxidant enzyme genes response. Rice seeds with in vivo method were soaked with no treatment (control) and 100 μM Potassium Dichromate (K2Cr2O7). The results obtained chromium significantly effects on the radicle length of rice seeds treated with stress. This study was viewed in detail with the in vitro method with callus formation on the induction media for 2 weeks after planting (WAP) and transferred into the regeneration media with control and stress treatment. Callus 2 WAP in regeneration media can be detected embryogenic properties by double staining of cell cytochemistry using Acetocarmine and Evans Blue compounds. Some varieties were confirmed to be resistant to chromium compounds characterized by absorbing a lot of Acetocarmine compounds, calluses producing green spots, regenerating from globular to coleoptillar stages, and developing into plantlets. Antioxidant enzyme genes and metabolite genes were expressed in shoot varieties that are considered resistant to chromium. The percentage of bands produced in chromium treatment was lower than controls, indicating that chromium had no effect on antioxidant enzyme activation.