Thiourea, a ROS Scavenger, Regulates Source-to-Sink Relationship to Enhance Crop Yield and Oil Content in Brassica juncea (L.)

Abstract

In the present agricultural scenario, the major thrust is to increase crop productivity so as to ensure sustainability. In an earlier study, foliar application of thiourea (TU; a non physiological thiol based ROS scavenger) has been demonstrated to enhance the stress tolerance and yield of different crops under field condition. Towards this endeavor, present work deals with the effect of TU on photosynthetic efficiency and source-to-sink relationship of Indian mustard (Brassica juncea) for understanding its mode of action. The application of TU increased the efficiency of both PSI and PSII photosystems and vegetative growth of plant. The comparative analysis of sucrose to starch ratio and expression level of sugar transporters confirmed the higher source and sink strength in response to TU treatment. The biochemical evidence in support of this was derived from higher activities of sucrose phosphate synthase and fructose-1,6-bis-phosphatase at source; and sucrose synthase and different classes of invertases at both source and sink. This indicated an overall increase in photoassimilate level at sink. An additional contribution through pod photosynthesis was confirmed through the analysis of phosphoenol pyruvate carboxylase enzyme activity and level of organic acids. The increased photoassimilate level was also co-ordinated with acetyl coA carboxylase mediated oil biosynthesis. All these changes were ultimately reflected in the form of 10 and 20% increase in total yield and oil content, respectively under TU treatment as compared to control. Additionally, no change was observed in oil composition of seeds derived from TU treated plants. The study thus signifies the co-ordinated regulation of key steps of photosynthesis and source-to-sink relationship through the external application of TU resulting in increased crop yield and oil content.

Promotive effect of exogenously applied thiourea on key physiological parametersand oxidative defense mechanism in salt-stressed Zea mays L. plants

“…In the current study, F v / F m of both maize cultivars increased due to exogenously applied TU under saline conditions, which is parallel to the findings of Pandey et al (2013), who documented improved chlorophyll fluorescence in salt stressed Indian mustard (Brassica juncea) plants due to exogenously applied TU and they attributed this growth improvement to TU-induced high efficiency of PSI and PSII. About two decades ago, Sahu et al (1993) observed that exogenously applied TU enhanced the photosynthetically active leaf area as well as the rate of photosynthesis in maize plants, which was ascribed to TU-induced improvement in the efficiency of photosystems.…”

Exogenous application of plant growth regulators (PGRs) induces chilling tolerance in short-duration hybrid maize

“…The present study aimed to investigate the effects of different natural and synthetic growth regulators for autumn-planted maize under Values are the means of three replicates ± SE CWP crop water productivity, WUE water use efficiency, SA salicylic acid, SWE sorghum water extract, MLE moringa leaf extract, TU thiourea and thus helped in yield improvement (Table 1). This stimulation in growth and physiological traits may be attributed towards foliar agents' (TU, SA) ability to stabilize redox homeostasis due to their ROS scavenging activity under stress conditions as previously reported by Ahmad et al (2014) and Pandey et al (2013). Larger leaves (higher LAI) enabled plants to capture sunlight more efficiently and thus improved maize growth in terms of CGR (Fig.…”

“…Improvement in the oxidative defense system and plant growth and development under different stress conditions due to TU application was observed in many crops like maize (Kaya et al 2013;Sahu et al 1993), wheat (Asthir et al 2013;Sahu et al 2005), pearl millet (Parihar et al 1998), and Brassica juncea (Srivastava et al 2009;Srivastava et al 2010a;Srivastava et al 2010b). TU was also reported to improve the photosystem efficiency, vegetative growth, and improved regulation of the source-sink relation in B. juncea (Pandey et al 2013).…”

Response of Thiourea Application on Dehydrogenase Activity in Soil, Yield and Oil Content of Niger [Guizotia abyssinica (L.f.) Cass.] under Rainfed Conditions of Bastar Plateau Zone

“…Similar findings were reported by Pandey et al, (2013) in Indian mustard. The increase in oil yield was attributed due to conversion of unloaded sucrose inside the pod into triose phosphate which finally gets converted into pyruvate (PYR) either through glycolytic pathway or phosphoenol pyruvate carboxylase (PEPC) mediated C4 pathway.…”