Microscopic study of nine galls induced in Populus nigra by aphids of the Iberian Peninsula

[EN] Aphids (Hemiptera, Aphididae) feed on the phloem and some of them induce the formation of conspicuous galls on their primary hosts. Histological studies were proposed to elucidate the evolutionary history of galling habit in Pemphigini tribe, assessing if gall complexity indicates the phylogenetic relations among gall inducers. Nine Eriosomatinae galls induced on Populus nigra from the Iberian Peninsula were studied microscopically. The galls are induced by Pemphigini of the genera Thecabius (2 galls) and Pemphigus (7 galls). Using multiple correspondence analysis of the observed microscopic characteristics, a hierarchical cluster was obtained showing the existence of 2 groups of galls. One group consists of the 2 galls induced by Thecabius and, within the genus Pemphigus, those belonging to the subgenus Pemphigus (P. populi and P. vesicarius). The other group consists of galls of the genus Pemphigus, subgenus Pemphiginus (P. bursarius, P. immunis, P. spyrothecae, P. protospirae and P. populinigrae). The gall histological complexity is related to Pemphigini phylogeny, confirming the importance of such studies in galling aphid taxonomy and possible pathways of galling habit evolution. Similarities are established between the galls of Pemphigini aphids studied here with others we studied microscopically, induced by Fordini and Eriosomatini. Finally, a classification of all Eriosomatinae galls is proposed, establishing 3 groups: galls that cause severe malformations (induced by derived galling taxa), those that cause less severe malformations, and those that cause mild malformations (pseudogalls). It also demonstrates the importance of the strategy of waste evacuation in derived galling speciesS

Histological Study of Leaf Galls Induced by Phylloxera in Vitis (Vitaceae) Leaves

[EN] The galls induced by hemipterans generally show hypertrophy of the phloem; these insects usually feed on the sap in the sieve tube elements, occasioning phloem bundle hypertrophy. However, there are some exceptions; for example, the phylloxerids feed on the gall wall parenchyma. It has remained unknown, however, whether Daktulosphaira vitifoliae (the vine phylloxera) also causes hypertrophy of the phloem bundles. The galls induced by D. vitifoliae in leaves of the rootstock variety Richter-110 (Vitis berlandieri × Vitis rupestris) were examined microscopically. D. vitifoliae was found capable of inducing vascular bundle hypertrophy, as well as the nutritional enrichment of the gall wall parenchyma cells upon which the insect feeds. The hypertrophy of the phloem bundles commonly seen in hemipteran-induced leaf galls also occurs in those induced by D. vitifoliae, even though these do not feed on the phloem contents, but rather on the gall wall parenchyma. The appearance of phloem bundle hypertrophy in hemipteran-induced leaf galls requires the remobilization of photoassimilates that might affect the productivity of the affected plantS

Racial differences in systemic sclerosis disease presentation: a European Scleroderma Trials and Research group study

Objectives. Racial factors play a significant role in SSc. We evaluated differences in SSc presentations between white patients (WP), Asian patients (AP) and black patients (BP) and analysed the effects of geographical locations.Methods. SSc characteristics of patients from the EUSTAR cohort were cross-sectionally compared across racial groups using survival and multiple logistic regression analyses.Results. The study included 9162 WP, 341 AP and 181 BP. AP developed the first non-RP feature faster than WP but slower than BP. AP were less frequently anti-centromere (ACA; odds ratio (OR) = 0.4, P < 0.001) and more frequently anti-topoisomerase-I autoantibodies (ATA) positive (OR = 1.2, P = 0.068), while BP were less likely to be ACA and ATA positive than were WP [OR(ACA) = 0.3, P < 0.001; OR(ATA) = 0.5, P = 0.020]. AP had less often (OR = 0.7, P = 0.06) and BP more often (OR = 2.7, P < 0.001) diffuse skin involvement than had WP.AP and BP were more likely to have pulmonary hypertension [OR(AP) = 2.6, P < 0.001; OR(BP) = 2.7, P = 0.03 vs WP] and a reduced forced vital capacity [OR(AP) = 2.5, P < 0.001; OR(BP) = 2.4, P < 0.004] than were WP. AP more often had an impaired diffusing capacity of the lung than had BP and WP [OR(AP vs BP) = 1.9, P = 0.038; OR(AP vs WP) = 2.4, P < 0.001]. After RP onset, AP and BP had a higher hazard to die than had WP [hazard ratio (HR) (AP) = 1.6, P = 0.011; HR(BP) = 2.1, P < 0.001].Conclusion. Compared with WP, and mostly independent of geographical location, AP have a faster and earlier disease onset with high prevalences of ATA, pulmonary hypertension and forced vital capacity impairment and higher mortality. BP had the fastest disease onset, a high prevalence of diffuse skin involvement and nominally the highest mortality

Histological Study of Leaf Galls Induced by Phylloxera in Vitis (Vitaceae) Leaves

The galls induced by hemipterans generally show hypertrophy of the phloem; these insects usually feed on the sap in the sieve tube elements, occasioning phloem bundle hypertrophy. However, there are some exceptions; for example, the phylloxerids feed on the gall wall parenchyma. It has remained unknown, however, whether Daktulosphaira vitifoliae (the vine phylloxera) also causes hypertrophy of the phloem bundles. The galls induced by D. vitifoliae in leaves of the rootstock variety Richter-110 (Vitis berlandieri × Vitis rupestris) were examined microscopically. D. vitifoliae was found capable of inducing vascular bundle hypertrophy, as well as the nutritional enrichment of the gall wall parenchyma cells upon which the insect feeds. The hypertrophy of the phloem bundles commonly seen in hemipteran-induced leaf galls also occurs in those induced by D. vitifoliae, even though these do not feed on the phloem contents, but rather on the gall wall parenchyma. The appearance of phloem bundle hypertrophy in hemipteran-induced leaf galls requires the remobilization of photoassimilates that might affect the productivity of the affected plant