Unraveling rice tolerance mechanisms againstSchizotetranychus oryzaemite infestation

Abstract

6Infestation of Schizotetranychus oryzae (Acari: Tetranychidae) causes great losses in 3 7 rice productivity. Infestation in Puitá INTA-CL cultivar reduced the number of 3 8 seeds/plant, percentage of full seeds, 1,000 seeds weight, and seed length, whereas 3 9 infestation in IRGA423 increased 1,000 seeds weight and seed length. Reduction in 4 0 seed weight/plant caused by infestation was higher in Puitá INTA-CL than IRGA423. 4 1 Thus, Puitá INTA-CL was established as susceptible, and IRGA423 as tolerant to S. 4 2 oryzae infestation. Photosynthetic parameters were less affected by infestation in 4 3 IRGA423 than in Puitá INTA-CL. Infestation also caused accumulation of H 2 O 2 , 4 4 decreased cell membrane integrity and accelerated senescence in leaves of Puitá INTA-4 5 CL, while leaves of IRGA423 presented higher levels of phenolics compounds. Using 4 6 proteomic analysis, we identified proteins related to plant defense, such as jasmonate 4 7 synthesis, and related to other mechanisms of tolerance such as oxidative stress, 4 8 photosynthesis, and DNA structure maintenance, more abundant in IRGA423 after 4 9 7 1damage caused by arthropod pests can exceed 15% annually (Mitchell et al., 2016). In 7 2 order to quantify the pest resistance of the cultivars, the best tool does not seem to be 7 3 the increase of the arthropod population, but the measurement of the damages caused to 7 4 the plants, since the reduction of the leaf damage is followed by an increase in yield and 7 5 quality of the grain, and these are the ultimate objectives of most crop breeding 7 6 programs (Smith, 2005). Thus, the plant resistance/tolerance to arthropods is the sum of 7 7 genetically inherited traits that result in an adapted species that suffers less damage 7 8 compared to susceptible ones. These resistance/tolerance qualities should be measured 7 9 on a relative scale by comparing levels of damage and productivity with susceptible 8 0

Reactive oxygen species metabolism and photosynthetic performance in leaves of Hordeum vulgare plants co-infested with Heterodera filipjevi and Aceria tosichella

“…The reduction of photosynthesis may be induced by either direct mesophyll damage and a significant reduction in stomatal conductance (Fadini et al 2004 ) or disorders in the transcription and translation of proteins associated with the photosynthetic apparatus (Schmitt et al 2014 ) or disruptions in the synthesis pathway of chlorophylls and carotenoids (Bronner et al 1991 ). It was shown that reduced photosynthesis efficiency in rice plants can be caused not only by a decrease in chlorophyll content (Buffon et al 2016 , 2018 ) but also by down-regulation of seven proteins synthesis related to NADPH production and thus to adenosine triphosphate and glucose synthesis (Blasi et al 2017 ). In the presented experiment, however, no significant differences were observed in the efficiency of photosynthesis (PN), transpiration (E), as well as in stomatal conductance (Gs) between barley plants inoculated and uninoculated with CCN and WCM.…”

“…All these limitations lead to generation of ROS, RNS and organic radicals causing irreversible destruction of the photosynthetic apparatus (Kalaji et al 2016 ; Tokarz et al 2020a ). Kinetic of chl a fluorescence revealed that rice plants sensitive to mite feeding had a significantly lower number of open PSII RC (F 0 ) among all PSII RC (Vj) as well as significantly lower efficiency of trapped energy flux (TRo/CSo) compared to resistant plants (Buffon et al 2018 ). At the same time, sensitive cultivars dissipated more intensely part of the trapped energy (Dio/RC) (Buffon et al 2018 ).…”

Unraveling Rice Tolerance Mechanisms Against Schizotetranychus oryzae Mite Infestation

“…The authors thank Instituto Rio-Grandense do Arroz (IRGA) for technical support, and José Rafael Wanderley Benicio and Rafael Spiekermann for the use of stereomicroscope. This present manuscript is available as a preprint ( Buffon et al, 2018 ), with the copyright holded by the authors.…”

Analysis of leaf morphology, secondary metabolites and proteins related to the resistance to Tetranychus cinnabarinus in cassava (Manihot esculenta Crantz)

“…The interaction between plants and pests is one of the important factors affecting plant productivity in both artificial and natural systems 8 . The leaf tissues are often the main target for different pests.…”

“…Moreover, phenolics can be toxic to insects and affect the feeding, growth, development and reproduction of T. cinnabarinus . Buffon et al 20 showed that the content of total phenolic compounds in the infested leaves of the tolerant cultivar rice varieties was higher than that of susceptible rice varieties.…”