Unveiling the Feeding Behavior of Tibraca limbativentris (Hemiptera: Pentatomidae) on Rice Using an Electropenetrography Waveform Library

Abstract

The rice stalk stink bug, Tibraca limbativentris Stål, damages plant stalks while feeding, making it one of the most important rice pests in South America. Because the feeding behavior of T. limbativentris has not yet been studied in rice, we investigated T. limbativentris stylet penetration (probing) in rice stalks. A waveform library was created using the new AC-DC EPG monitor with different levels of input resistance (Ri). Six different waveforms were recorded and correlated via histological studies and grouped into three phases: non-probing waveforms (Z and Np), pathway waveforms (Tl1), and ingestion waveforms (Tl2 and Tl3). The Z waveform was observed when the stink bug was standing still on the plant surface, Np when the stink bug was walking on plant surface, Tl1 was associated with stylet insertion and deep penetration into the plant tissue, and Tl2 when the stink bug was feeding on xylem vessels. The Tl3 waveform was associated with the rupture of stalk cells and was divided into two subtypes (Tl3a and Tl3b). The Tl3a waveform probably represents cell laceration with combined enzymatic maceration of stalk tissues, while Tl3b represents a short ingestion period of macerated tissues. Tibraca limbativentris uses two strategies to feed on rice stalks: a salivary sheath for feeding on xylem vessels and cell rupture (laceration and maceration) for feeding on parenchyma cells. Our study provides crucial benchmark definitions of waveforms. Future studies can now compare effects of treatments on stink bug feeding, to ultimately improve management of this pest in rice.

Feeding Behavior of Riptortus pedestris (Fabricius) on Soybean: Electrical Penetration Graph Analysis and Histological Investigations

“…Waveforms were further grouped into nonprobing, pathway, xylem sap ingestion, salivation and ingestion, and interruption phases ( Table 1 and Figure 1 , Figure 2 and Figure 5 ). In comparison with the waveforms recorded from Pentatomidae species, we found that the Rp2 waveform varied in different plant tissues, which is consistent with the DM2 waveforms of Dichelops melacanthus on maize seedlings [ 31 ] and Tibraca limbativentris on Rice [ 18 ]. For the cell rupture strategy employed by R. pedestris , it is hard to distinguish the waveform salivation from ingestion, so salivation/ingestion was defined together as Rp3, the same as the NV3 of Nezara viridula [ 32 ].…”

“…The detailed waves and peaks of Rp3 are illustrated in Figure 4 . Cell-rupture strategy defined by Backus comprised of two different types of waveforms: salivation (cell laceration and maceration of cell tissues) and ingestion (short ingestion of lacerated/macerated cell contents) [ 13 ], which is true for Piezodorus guildinii [ 29 ], Halyomorpha halys [ 28 ], Dichelops furcatus [ 30 ], Euschistus heros [ 24 ], and Tibraca limbativentris [ 18 ]. However, the waveforms of salivation and ingestion are not clearly distinguished in the case of R. pedestris , so we defined salivation/ingestion as Rp3.…”

“…EPG allows researchers to analyze various insect stylet activities within plant tissues, including stylet penetration (i.e., inter- versus intracellular), saliva secretion, sap ingestion, and cell rupture [ 14 ]. This technique has been used to evaluate the feeding behavior of many herbivorous insects within Hemiptera, such as whitefly, aphid, and psyllids (Stemorrychans) [ 8 , 15 , 16 ]; leafhoppers and planthoppers (Auchaenorrhynchans) [ 17 ]; and stink bugs (Heteropterans) [ 18 ]. In 1972, Miles proposed that all hemipterans use one of two different feeding strategies: sheath feeding and lacerate-and-flush feeding [ 19 ].…”

“…Since they acquire nutrients from phloem sap, these species are usually referred to phloem feeders [ 20 , 21 ]. Most of the species within heteropterans use cell-rupture tactics to feed, including the Miridae, such as Lygus lineolaris and Collaria scenica [ 22 , 23 ], and Pentatomiae species, for example, Euschistus heros and Tibraca limbativentris , which ingest water from xylem vessels and obtain nutrients using cell-rupture feeding from soybean and rice [ 18 , 24 ]. For the members of Coreidae within Heteroptera, only the feeding behavior of Anasa tristis was recorded with EPG so far [ 25 , 26 ], and there is no record of the feeding strategy of R. pedestris .…”

Natural incidence of pathogenic fungi on stink bug pests in Argentinian rice paddies

“…Among the hemipteran pests in the Neotropics, stink bugs of the genera Tibraca and Oebalus (Hemiptera: Pentatomidae) represent a serious challenge for rice production (Pantoja et al, 1997; Didonet et al, 2001; Kruger & Burdyn, 2015). Tibraca limbativentris Stål is stem‐feeding and damages the plant in two ways: a salivary sheath is formed when ingesting the contents of xylem vessels, and cells get ruptured by laceration and maceration when ingesting the contents of parenchyma cells (Almeida et al, 2020). During its feeding process, this pest injects saliva and sucks out the contents of plant tissues, damaging the stem, which leads to yield reduction.…”