Seed nano-priming with Zinc Oxide nanoparticles in rice mitigates drought and enhances agronomic profile

Abstract

All cereal crops, particularly rice are perpetually affected due to drastic climatic changes which triggers different stressors resulting in food shortage scenarios across the globe. In modern era, application of nanotechnology holds the pledge in combating the climate change mediated environmental stressors through nanomaterials such as pesticides, nano-biosensors, nano-clays and nano-seed priming technologies. Current study is a part of experiment conducted to comprehend the behaviour of rice plants raised from Zinc Oxide nanoparticles (ZnONPs) primed seeds under the water shortage environment. The seed priming treatment concentrations included 0, 5, 10, 15, 25 and 50 ppm. In the experimental results an increase in plant height, total chlorophyll contents, plant fresh and dry weights was obtained by use of seed priming with ZnONPs. The study results proved that seed priming with 25ppm of ZnONPs increased seed and straw yield with value of 85.333 and 123.333, respectively under water deficit environment. The analysis depicted that 25 ppm has been found more suitable for increasing the 1000 paddy weight of rice plants under both well irrigated and water shortage conditions. Seed priming with ZnONPs results in 53% reduction in MDA contents of water stressed rice plants Drought stress leads to reduction in plant height by 31%, plant fresh weight by 22% and plant dry weight by 28%. Seed priming treatments imparted in current study show significance increase in plant biomass. Priming with ZnONPs further enhances the levels of proline amino acid facilitating the plant to combat water shortage stress. A further elevation in activities of SOD, CAT and POD takes place in rice plants raised from ZnONPs primed seeds by 11%, 13% and 38%, respectively. An elevation in activities of antioxidant enzymes was found and the levels of oxidative stress indicators decreased upon seed priming with ZnONPs. Furthermore the yield characteristics such as panicle length, number of tillers, paddy yield and straw yield of the rice plants raised through ZnONPs primed seeds enhanced. The ZnONPs at concentration of 25 ppm proved optimum in alleviating drought induced damages. It can be inferred that seed pre conditioning with ZnONPs is helpful in increasing yield attributes under the water shortage environment.