Awn Removal Research Articles

Application of Ultrasound in Detecting and Removing Migrating Grass Awns in Dogs and Cats: A Systematic Review.

Migrating grass awns are an important cause of disease in dogs and cats. Plant awns can migrate into several body tissues and cavities because of their fusiform shape and backward-pointing barbs. Their migration causes inflammatory tissue reaction and clinical signs depend upon their localization. Ultrasound has been described as a useful, noninvasive, and readily available tool to identify and guide vegetal foreign bodies removal in animals. The aim of this systematic review was to summarize current knowledge on the application of ultrasonography in the identification and removal of grass awns from various anatomic locations in dogs and cats. We selected and analyzed 46 papers on the application of ultrasonography in dogs and cats affected by migrating grass awns. The ultrasonographic appearance of grass awns is characteristic, although their size and location can influence the visualization and the attempt of removal. In some cases, migrating grass awns are not directly visualized by ultrasonography, but the lesions caused by their migration can be easily seen. Ultrasonography can be considered a useful diagnostic tool to localize and remove migrating grass awns; however, when the migration occurs in less accessible locations or discrete foreign bodies are present, this diagnostic tool should be considered as a part of a multidisciplinary approach with advanced diagnostic imaging modalities.

Trade-offs between diaspore dispersal and dormancy within a spike of the invasive annual grass Aegilops tauschii.

Differences in dispersal and dormancy of heteromorphic diaspores of Aegilos tauschii may increase its flexibility to invade/occupy weedy unpredictable habitats by spreading risk in space and time. In plant species that produce dimorphic seeds, there often is a negative relationship between dispersal and dormancy, with high dispersal-low dormancy in one morph and low dispersal-high dormancy in the other, which may function as a bet-hedging strategy that spreads the risk of survival and ensures reproductive success. However, the relationship between dispersal and dormancy and its ecological consequences in invasive annual grasses that produce heteromorphic diaspores is not well studied. We compared dispersal and dormancy responses of diaspores from the basal (proximal) to the distal position on compound spikes of Aegilops tauschii, an invasive grass with heteromorphic diaspores. Dispersal ability increased and degree of dormancy decreased as diaspore position on a spike increased from basal to distal. There was a significant positive correlation between length of awns and dispersal ability, and awn removal significantly promoted seed germination. Germination was positively correlated with GA concentration and negatively correlated with ABA concentration, and the ABA: GA ratio was high in seeds with low germination/high dormancy. Thus, there was a continuous inverse-linear relationship between diaspore dispersal ability and degree of dormancy. This negative relationship between diaspore dispersal and degree of dormancy at different positions on a spike of Aegilops tauschii may facilitate seedling survival in space and time.

Infected parotid sialocele treated by vegetal foreign body removal in a dog

AbstractAn 11‐month‐old French bulldog was presented for a recurrent fluid‐filled mass located ventral to the right pinna. An infected parotid sialocele was diagnosed using ultrasonography, computed tomographic sialography and cytological analysis of the fluid. The dog also had a superficial corneal ulcer because of iatrogenic right facial nerve paralysis secondary to previous attempts by the referring veterinarian to excise the mass surgically. Vegetal foreign bodies (grass awns barbs) were found at the entrance to the right parotid canal and were removed with iris forceps. Bacteriology was positive for Streptococcus canis. Conservative management was initiated after grass awn removal, and the dog was discharged with oral antibiotics (amoxicillin‐clavulate orally), ophthalmic antibiotic ointment and artificial tears. Clinical signs related to parotid sialocele resolved, and permanent partial temporal tarsorrhaphy was performed 2 months later. At the 3‐year follow‐up, the dog had no signs of recurrence of the parotid sialocele, but facial paralysis was still present.

Photosynthetic organs contributions to grain yield genetic gains in Chilean winter wheat

AbstractInvestigating the key traits associated with genetic gains in grain yield (GY) is essential for developing winter wheat (Triticum aestivum L.) breeding strategies. The study objectives were: (a) quantifying the photosynthetic contribution of flag leaf and ear to the grain filling; (b) analyzing if their contributions are associated with the genetic gains in GY; and (c) analyzing their relationship with other agronomical and physiological traits. Thus, six winter wheat genotypes of different release years were grown under optimal conditions in a greenhouse trial during 2019. Grain yield increased by 126 kg h–1 yr–1, with the harvest index's change being the key factor affecting these gains. Compared to the control treatment, ear shading decreased ear contribution to grain filling by 16.35%, while both flag leaf and awn removal increased contribution to grain filling by 4.46 and 5.90%, respectively. Ear photosynthetic contribution estimated by source manipulation treatments showed a significant increase with the release year (0.54% yr–1). Whole ear gas exchange measures correlated positively with GY, and both dark respiration and gross photosynthesis showed positive correlations with the release year. The main findings of the study were: (a) GY gains in Chile were mainly due to the increased harvest index (HI), while the aerial biomass (AB) did not play a significant role in these gains; (b) the increased ear size besides the terminal heat stress during the study highlighted the ear role as the primary photosynthetic contributor to grain filling; and (c) using source manipulation techniques as an indirect selection trait for high ear photosynthesis appeared to be promising.

Decoding the wheat awn transcriptome and overexpressing TaRca1β in rice for heat stress tolerance.

Role of Rubisco Activase in imparting thermotolerance to the photosynthetic apparatus under high temperature. Thus, to improve the grain filling, we need to fine tune these crucial enzymes and their regulation, which directly or indirectly affect spike photosynthesis. CO2 fixation in cereals crops like bread wheat (Triticum aestivum L.) is also contributed by ear photosynthesis beside the other organs like leaves or the flag leaf. 1000-grain weight of three Indian wheat cultivars (cvs.) PBW343, K7903, and HD2329 were calculated under three treatments until maturity stage (i.e. removal of flag leaf, removal of awns and shaded spikes). We observed that awn removal showed a significant decrease in 1000-grain weight in all cultivars. To delve deeper into the biological and molecular pathways taking place underlying the awn physiology, we conducted the awn transcriptome analysis of thermosusceptible Indian wheat cv. PBW343 under heat stress (HS) at 42°C for 2h using RNA-sequencing (RNA-seq). Differential expression analysis revealed, 160 transcripts, out of these, 143 transcripts were significantly upregulated and 17 transcripts were repressed under HS conditions. Of these Rca1β was selected for characterization and overexpression studies. Ectopic expression of TaRca1β in rice transgenics indicate a direct correlation with tolerance under HS conditions. TaRca1β provides a better photosynthate energy partitioning under HS with a significant reduction in the non-photochemical fluorescence quenching of the photosynthetic machinery.

Grazing influences Stipa breviflora seed germination in desert grasslands of the Inner Mongolia Plateau.

Seed germination plays an important role in determining the composition and regeneration of plant populations (Stipa breviflora). However, the influencing factors and strategies employed for seed germination in desert grasslands under grazing remain unknown. Therefore, in this study, the reproductive allocation, seed density, seed properties, and corresponding seed germination rates of S. breviflora were examined. Possible situations encountered during dispersal were also simulated to determine their effects on seed germination. The results showed that reproductive individual density not subjected to grazing were significantly higher than those subjected to moderate and heavy grazing. For seed density and seed bank in soil, the highest values were observed for the no grazing treatment, followed by the moderate and heavy grazing treatments. The seed density for germination of soil seed banks was nearly one-fourth of seed density during the growing season. In addition, grazing treatments affected the phenotypic characteristics of seeds and reduced the lower limit of the weight of germinable seeds. Awn removal significantly increased germination. The longest germination time was observed for seeds that entered the soil at an angle of 0°. Our research demonstrated that grazing negatively affected the desert grassland edificator. Individual plants adopted different adaptation strategies under different grazing intensities; for example, a fixed proportion of the seed number and seed germination number of S. breviflora in the soil seed bank was maintained by exceeding the minimum weight of a seed for seed germination. During seed dispersion, the awn effectively prevented germination under unfavourable conditions and helped seeds enter the soil at an optimal angle for promoting germination.

Effect of sowing dates, seeding rates, awn and flag leaf removal on yield and its components of Adana-99 bread wheat cultivar

Effect of sowing dates, seeding rates, awn and flag leaf removal on yield and its components of Adana-99 bread wheat cultivar

FUNÇÃO DAS ARISTAS SOBRE CARACTERÍSTICAS DA SEMENTE DE TRIGO

The purpose of this study was to determine the influence of the presence of awns in wheat ears on the physiological seed quality, and its effect on some grain characteristics and seedlings produced under field conditions in the northwest of Rio Grande Sul State. The experiment was conducted at the Experimental Field of the University of Cruz Alta Agronomy Course, Cruz Alta, northwestern region of Rio Grande do Sul, in soil Oxisoil. The experimental design was a randomized block design with plots of four rows of 5m long, cm spacing of 0,17m and six replications. Four treatments were evaluated: with awn, without awn, removal of 100% of the awns and removing 50% of the awns. The results showed that awned wheat genotypes have thousand seed weight superior to awnless wheat genotypes or genotypes with removal of awns.

The role of flag leaf blade and awns on yield and its components of some bread wheat varieties at two locations of sulaimani region

This investigation was conducted during the growing season of 2009-2010, attwo different locations (Qlyasan Agriculture Research Station, College of Agriculturalsciences- University of Sulaimani, and farm land in Dukan), using split-split plots designin RCBD with four riplications. Four common wheat varieties of different origins (Araz,Tamuz, Rabea'a, and Cham-4) were used grown and implemented in the main plots. Fourseeding rates of (120, 160, 200, and 240) kg/ ha implemented in the sub-plots as thesecond factor, while four leaf and awn removal treatments as the third factor wereimplemented in the sub-sub plots that were (control, flag leaf blade removal, awnsremoval, and flag leaf blade + awns removal). Grain yield with some of its components were measured such as number of spikes/ m 2 , spike weight/ m 2 , spike length, number of spikelets/ spike, number of grain/ spike, grain weight/ spike, 1000- grain weight, and grain yield). Data on biological yieldand harvest index were also recorded. The results of grain yield and its components with biological yield, and harvestindex can be summarized as the average of both locations as follows: the effect of varieties on these characteristics was highly significant, Araz variety showed maximum values for the characteristics: number of spikes/ m 2 , spike weight/ m 2 , average spike length, and harvest index. Tamuz variety exhibited maximum number of spikelets/ spike,and grain number/ spike, while Rabea'a variety showed maximum values for the characteristics: grains weight/ spike, 1000- grains weight, grain yield, and biological yield. However, Tamuz variety produced minimum values for the characteristics; spike weight/ m 2 , grain weight/ spike, 1000- grains weight, grain yield, biological yield, and harvest index. The effect of seeding rates on yield characteristics and its components as the average of both locations was highly significant on number of spike / m 2 , spikeweight/ m 2 , grain yield, and biological yield only, using the seed rate of 240 kg/ ha exhibited maximum values for these characteristics, while 120 kg/ ha seeding rate showed minimum values in number of spikes / m 2 , grain yield, and biological yield.Regarding the effect of removal treatments on yield characteristics, and its components as the average of both locations, the characteristics, number of spikes/ m 2 , spike weight/ m 2 , grain weight/ spike, 1000- grains weight, grain yield, and biologicalyield highly significant responded to these effects. While the characteristics number of spikelets/ spike, significantly responded, and the characteristics average spike length, number of grains/ spike, and harvest index showed no significant respons. The controltreatments produced maximum values of yield and its components, while removing both flag leaf blade + awn showed minimum values in spike weight/ m 2 , grains weight/ spike, 1000- grains weight, and grain yield.

Ultrasonographic findings and outcomes of dogs with suspected migrating intrathoracic grass awns: 43 cases (2010-2013).

To describe ultrasonographic findings and outcomes for dogs with suspected migrating intrathoracic grass awns. Retrospective case series. 43 client-owned dogs. Records for dogs with suspected migrating intrathoracic grass awns examined between 2010 and 2013 were reviewed. Ultrasonographic images and additional information such as signalment and pleural fluid analysis, radiographic, bronchoscopic, and CT findings were collected. Surgical treatments and outcomes were also reviewed. Transthoracic or transesophageal ultrasonography revealed grass awns in the pleural space (n = 13) or pulmonary parenchyma (10) of 23 dogs. Surgical removal of grass awns was successful on the first attempt in 21 of these 23 dogs (including 11/23 that had intraoperative ultrasonography performed to aid localization and removal of the awn). In the remaining 2 dogs, a second surgery was required. Twenty dogs with evidence of migrating intrathoracic grass awns had no foreign body identified on initial ultrasonographic evaluation and were treated medically; 16 developed draining fistulas, and awns identified ultrasonographically at follow-up visits were subsequently removed from the sublumbar region (n = 10) or thoracic wall (6). The remaining 4 dogs had no grass awn visualized. Clinical signs resolved in all dogs. Transthoracic, transesophageal, and intraoperative ultrasonography were useful for localization and removal of migrating intrathoracic grass awns. Ultrasonography may be considered a valuable and readily available diagnostic tool for monitoring dogs with suspected migrating intrathoracic grass awns.

The contribution of ear photosynthesis to grain filling in bread wheat ( Triticum aestivum L.)

The contribution of ear photosynthesis to grain filling in wheat ( Triticum aestivum L.) is not well known. The main objective of this work was to evaluate this contribution through three different experimental approaches: (1) ear photosynthesis was reduced by removing awns or shading the ears (in combination with a defoliation treatment), (2) grain weight per ear was compared in an ‘all shaded’ crop versus plants where only the vegetative parts were shaded (‘ear emerging’), and (3) ear photosynthesis was reduced with DCMU (3-(3,4-dichlorophenyl)-1,1-dimethylurea), a specific inhibitor of photosystem II. In field experiments in La Plata (Argentina), cultivars Klein Escudo and BioINTA 3000 were subjected to awn removal and ear shading treatments, with or without severe defoliation, and to ‘all canopy shaded’ versus ‘ear emerging’ treatments. Although the estimated contribution of ear photosynthesis to grain yield differed depending on the experimental approach used (from about 12–42%), in general cv. Klein Escudo (with the largest awns) showed a greater contribution of ear photosynthesis. In both cultivars, the percentage contribution of ear photosynthesis was larger for defoliated plants. The magnitude of this contribution was positively associated with the length of awns of each cultivar. Awn removal had a non-significant ( p ≤ 0.05) effect on grain weight per ear (GW ear) in the short-awned cv. BioINTA 3000. In cv. Klein Escudo, the effects of de-awning were larger, reaching values of ca. 15 and 19% decrease of GW ear in non-defoliated and defoliated plants respectively. In both cultivars, grains in a distal position within the spikelet (G3) were most affected by the decrease of the photosynthetic source. The photosynthetic rate of the ear was higher in cv. Klein Escudo than in cv. BioINTA 3000. We analyzed the contribution of remobilization of pre anthesis assimilates (stem plus sheaths). Comparing both cultivars, dry matter translocation from the stem showed the opposite pattern to the contribution of ear photosynthesis, i.e. it was higher in cv. BioINTA 3000 than in Klein Escudo. In Bordenave, Argentina, ear shading treatments revealed an important contribution of ear photosynthesis to grain yield in cv. Huenpan (a long awned, water-deficit tolerant genotype), either under water deficit or irrigation, whereas in cv. Baguette Premiun 11 (short awns) there was apparently no effect of ear photosynthesis on yield. Finally, inhibition of ear photosynthesis with DCMU reduced grain weight per ear to a similar extent as ear shading. Ear photosynthesis might represent a “buffer” to maintain grain yield under source limitations (e.g. defoliation, water stress conditions), and could have an important role even without stress, because an incipient ‘source’ limitation might be emerging in modern cultivars of bread wheat.

ULTRASOUND‐GUIDED RETRIEVAL OF PLANT AWNS

In dogs, surgical removal of plant awns causing a foreign body granuloma or abscess may be challenging. The inability to localize the foreign body during surgical removal often leads to abscess recurrence. In this report, we describe ultrasound-guided retrieval as an alternative to standard surgical retrieval in animals where the plant awn can be identified sonographically. This procedure was used in six dogs with a superficial abscess due to a plant awn, and in all dogs the foreign body was successfully retrieved with Hartmann forceps. No complication was observed and no abscess recurred. Minimally invasive ultrasound-guided plant awn retrieval appears to be a safe effective method of retrieving superficially located plant awns in the dog.

Awn contribution to gas exchanges of barley ears

The effects of awn removal on ear gas exchange in four barley lines (Morex, Harrington, Steptoe, and TR306) were studied under a controlled environment using a Before-After Control-Impact Paired (BACIP) experimental design. From ear emergence to grain maturity, plants were grown in pots at either 60 or 90 % of soil water holding capacity. Gas-exchange measurements of ears were made 9 and 10 d after anthesis (DAA). On 11 DAA, awn removal was performed on half of the ears in each pot, followed by measurements on both intact and de-awned ears on 12 and 13 DAA. Net photosynthetic (P N) and transpiration (E) rates decreased significantly with awn removal, but dark respiration (R D) rate was not affected. We estimated for each ear a temperature-adjusted respiration rate (R a) from R D. When we corrected P N with R a, we found that rates of spikelet photosynthesis were largely underestimated. Moderate water stress had minimal effect on gas exchange of bracts and awns of the barley ear. Barley lines did not differ for any individual gas-exchange parameter.

Effects of Shading and Flag Leaf or Awn Removal on Structure of Reserve Substances Accumulation in the Grain Endosperm of Two-rowed Barley

Effects of Shading and Flag Leaf or Awn Removal on Structure of Reserve Substances Accumulation in the Grain Endosperm of Two-rowed Barley

Manipulation of xylem transport affects Zn and Mn transport into developing wheat grains of cultured ears

Zinc and manganese loading into developing wheat grain is little understood at present. The objective of this work was to investigate factors that may affect the rate of transport of Zn and Mn into developing wheat grain of cultured ears. Ears 18‐22 days post‐anthesis were cultured in solutions containing labelled Zn and Mn. The effect of additions of Cu, Fe, citrate, malate and EDTA to the culture solution was observed. The effect of humidity and awn removal as well as the sucrose status of the ears on Zn and Mn transport was also investigated. The effect of high concentration of Zn and Mn on [14C]‐sucrose transport was determined. High humidity almost completely blocked transport of Zn and Mn into the grain. Awn removal reduced the transport of Zn and Mn to the lemma but not the grain. When the ears were depleted of sucrose (by maintaining them in the dark prior to labelling) transport of Zn and Mn to the grain was reduced compared to ears cultured with sucrose. The presence of Cu reduced the loading of Zn into the grain. There was little effect of Cu on Mn transport or Fe on either Zn or Mn transport. High concentrations of Zn and Mn in the culture solution did not affect [14C]‐sucrose loading into the grain but loading of Zn and Mn was limited at high concentrations suggesting membrane saturation. This study demonstrates that sucrose status and humidity clearly influence the transport of Zn and Mn into the grain, and that other ions may influence Zn and Mn transport.

Nitrogen and Carbon Isotope Composition of Wheat Grain: Alteration due to Sink-source Modifications at Flowering

An experiment of sink-source modifications was performed in field-grown wheat at flowering on five varieties (four Triticum aestivum and one T. durum); among these, two varieties were non-awned. The sink-source modifications were blade removal (treatment B) and blade deletion and stalk and sheaths darkening (treatment C). Intact plants (treatment A) acted as a control. In the three awned varieties, the effect of awn removal was also analysed. Two lots of tests were initially performed, with awns (treatments A+, B+, C+) or with awns removed (treatments A−, B−, C−). Yields and carbon and nitrogen isotope compositions were then determined on seeds harvested at maturity. Blade deletion reduced the yield by one third whereas additional stalk and sheaths darkening led to a two thirds decrease. Nitrogen yield was similarly affected but the deprivation due to treatment C was less marked for nitrogen than for carbon. Thus, treatment C produced grains which were notably richer in nitrogen than plants which had received treatment A and B. For each of the five varieties, the decrease in yield was highly correlated with a 13C enrichment of grains (roughly from −28 to −25‰). In contrast with the 13C variations, there was no general trend for 15N evolution among treated plants. The final yield for treated T. durum plants was strongly modified when the awns were removed at flowering whereas no significant variations were noted in the other T. aestivum awned varieties. T. durum seeds obtained from plants deprived of awns were notably depleted in 13C and in 15N compared to control plants. Isotope compositions of C and N of the different pools supplying the grain filling were estimated and discussed in the context of the physiology of the mother plants between flowering and maturity.

De-awning of Agropyron spicatum cultivator for use as an understory grass on erosive sites

South-facing, semi-arid slopes supporting sagebush (Artemisia tridentata) with scant understory are difficult sites for establishment of perennial vegetative cover in Central Washington. Blue-bunch wheatgrass (Agropyron spicatum) is the most ubiquitous, widely distributed native perennial where exotic annuals are a competitive problem. It can be found as an understory associate or in open stands.Secar is a cultivar, of A. spicatum developed in the Pacific Northwest. Unfortunately, the percent germination of secar seed has been found to be low. It was suspected that a possible inhibitor exists in the awn and mechanical removal may result in earlier and greater germinative ability for increased establishment on Conservation Reserve Program lands.It was found that total germination was not significantly affected by temperature treatment but an apparent difference in rate was determined. A significant increase in germination occurred with awn removal. Specific location of an inhibitor(s) was not statistically apparent. Key words: Agropyron spicatum, germination, seedling vigor, reseeding

Effect of flag leaf and awn removal on grain yield and yield components of wheat grown under dryland conditions

Abstract Effect of flag leaf and/or awn removal on grain yield, kernel number and single weight were investigated in nine durum ( Triticum durum Desf.) and one hexaploid ( Triticum aestivum L.) wheat genotypes grown under dryland conditions in Jordan. The treatments were control, removal of the flag leaf, removal of the awns, and a combination of awn and flag leaf removal. Genotypes studied differed in the traits investigated in addition to other agronomic characters. Flag leaf removal, awn removal and their combination significantly reduced grain yield by 10.7, 15.9 and 21.2%, respectively. Reduction in kernel number per plant was 11.1, 11.3, and 11.2%, respectively. Kernel weight was decreased by 5.2 and 11.3% as a result of awn removal and the combination treatment, respectively, but not by flag leaf removal. Although no genotype × treatment interaction was detected for any of the traits studied, grain yields of the local cultivars which are adapted to dryland conditions were affected more than other genotypes by awns' removal.

Influence of Age and Awn Removal on Dormancy of Medusahead Seeds

Influence of Age and Awn Removal on Dormancy of Medusahead Seeds