Interactions between brown planthopper (Nilaparvata lugens) and salinity stressed rice (Oryza sativa) plant are cultivar-specific

Abstract

Salinity stress triggers changes in plant morphology, physiology and molecular responses which can subsequently influence plant-insect interactions; however, these consequences remain poorly understood. We analyzed plant biomass, insect population growth rates, feeding behaviors and plant gene expression to characterize the mechanisms of the underlying interactions between the rice plant and brown planthopper (BpH) under salinity stress. plant bioassays showed that plant growth and vigor losses were higher in control and low salinity conditions compared to high salinity stressed TN1 (saltplanthopper susceptible cultivar) in response to BPH feeding. In contrast, the losses were higher in the high salinity treated tpX (salt-planthopper resistant cultivar). BpH population growth was reduced on TN1, but increased on TPX under high salinity condition compared to the control. This cultivar-specific effect was reflected in BPH feeding behaviors on the corresponding plants. Quantification of abscisic acid (ABA) and salicylic acid (SA) signaling transcripts indicated that salinity-induced down-regulation of ABA signaling increased SA-dependent defense in TN1. While, up-regulation of ABA related genes in salinity stressed TPX resulted in the decrease in SA-signaling genes. Thus, ABA and SA antagonism might be a key element in the interaction between BPH and salinity stress. Taken together, we concluded that plant-planthopper interactions are markedly shaped by salinity and might be cultivar specific. Plants are often exposed to multiple abiotic and biotic stressors at the same time in nature. For example, they may need to adapt to soil affected by salinity, heavy metals or drought as well as to attacks by herbivores and pathogens. Abiotic and biotic stresses interact at the cellular level and reaction to a combination of stresses, however, is often unique and cannot be explained from studying these stresses individually 1-4. Worldwide, increased soil salinity has negative impacts on about 30% of irrigated and 6% of the total land area 5. More than 397 million hectares of agricultural land in Africa, Asia, Australia and North and South America, have been affected by salinity 6 , with a monetary loss of 12 billion US$ in agricultural production 7. Salinization has increased due to the redistribution of salts in the soil during the conversion of wetlands or forests into farmland. Although the salinization of the soil occurs most in dry and semi-dry areas, it has been reported in almost all climatic areas 8. Better understanding of the plant adaptive mechanisms to cope with the abiotic as well as biotic stresses can help in the development of interventions. Salinity affects nutrient uptake, growth, ion homeostasis, general plant metabolism and water uptake in plants 9-11. This stress can also alter the direct and indirect immune metabolites of the plant 12. In addition, insect herbivory may be positively 13-15 , negatively 16-18 or neutrally 19,20 influenced by soil salinity. To date most studies have focused on direct effects...

Partial Substitution of K by Na Alleviates Drought Stress and Increases Water Use Efficiency in Eucalyptus Species Seedlings

“…We would like to emphasize that the Na rates employed in studies regarding salinity-induced stress in plants are higher than those used hereby. For instance, Zhang et al (2016) investigated salinity-induced stress on wheat seedlings’ growth in nutrient solution by adding a NaCl rate of 150 mM, while Quais et al (2020) characterized the mechanisms of the underlying interactions between rice plants and brown planthopper under salinity stress (100 mM salinity level). According to Madsen and Mulligan (2006) , the emergence of Eucalyptus citriodora , E. camaldulensis , Eucalyptus populnea , and Acacia salicina was substantially reduced by adding 100 mM of NaCl, while the survival of established plants was reduced only at 300 and 400 mM of NaCl.…”

Differential Impact of Nitric Oxide and Abscisic Acid on the Cellular and Physiological Functioning of sub1A QTL Bearing Rice Genotype under Salt Stress

“…The distribution of tissue-specific ROS accumulation irrespective of cultivar but with differential tolerance could imply NO sensitivity of those cultivars in a differential manner. On a comparative basis, the ABA could exceed responses for NOX activity more than NO and thereby raise the chances for more oxidative stress but it is rescued by existing antioxidation paths [68]. An equal possibility for both NO and ABA-induced antioxidation, particularly at the level of leaves and roots for O 2…”

Plant hormones and metabolites related to the resistance response to feeding stimulation and leaf clipping control in Chinese pine (Pinus tabuliformis Carr.)

“…Downregulation of ABA signaling induced by brown planthoppers can increase SA-dependent defense in response to salt stress in susceptible rice varieties (Quais, et al 2020). Similarly, the increase in ABA and JA content in rice after silencing E3 ligase also demonstrates brown planthopper-induced plant hormone antagonism (Zhang, et al 2021c).…”