Stress intensity and fitness in the parasitoid Aphidius ervi (Hymenoptera: Braconidae): temperature below the development threshold combined with a fluctuating thermal regime is a must

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Struggles for Indigenous Education and Self-Determination: Culture, Context, and Collaboration

These comments—by a Singaporean and an American—-focus on four themes: roles of anthropologists; the pedagogy of culture; challenges in combining Indigenous and mainstream epistemologies; and reciprocal influences between social and political contexts, and struggles for Indigenous education and self-determination.     

From kissing to belly stridulation: comparative analysis reveals surprising diversity,rapid evolution,and much homoplasy in the mating behaviour of 27 species of sepsid flies (Diptera: Sepsidae)

Our understanding of how fast mating behaviour evolves in insects is rather poor due to a lack of comparative studies among insect groups for which phylogenetic relationships are known. Here, we present a detailed study of the mating behaviour of 27 species of Sepsidae (Diptera) for which a well‐resolved and supported phylogeny is available. We demonstrate that mating behaviour is extremely diverse in sepsids with each species having its own mating profile. We define 32 behavioural characters and document them with video clips. Based on sister species comparisons, we provide several examples where mating behaviour evolves faster than all sexually dimorphic morphological traits. Mapping the behaviours onto the molecular tree reveals much homoplasy, comparable to that observed for third positions of mitochondrial protein‐encoding genes. A partitioned Bremer support (PBS) analysis reveals conflict between the molecular and behavioural data, but behavioural characters have higher PBS values per parsimony‐informative character than DNA sequence characters.     

A Comparison of Abscission of Rubber (Hevea brasiliensis) Leaves Infected with Microcyclus ulei with Leaf Abscission Induced by Ethylene Treatment, Deblading and Senescence

Studies on the histology and on effects of growth substancesand phenols as well as changes in activities of pectinmethylesterase indicated that the mechanism of abscission of Hevealeaflets infected with Microcyclus ulei differed from the mechanismof abscission of debladed, ethylene treated and senescent leaves.An abscission layer which was formed during abscission of debladed,ethylene-treated and senescent leaves was absent during abscissionof heavily diseased leaves. The ratio of pectinmethyl esteraseactivities in tissues distal to the abscission zone to activitiesin tissues proximal to the zone decreased in debladed and ethylenetreated leaves but such decreases were not detected during abscissionof Hevea leaves infected with M. ulei. Hevea brasiliensis Muell. Arg., rubber, leaf abscission, Microcyclus ulei, ethylene, indol-3-ylacetic acid, kinetin     

Nuclear binding sites for juvenile hormone III in the male accessory reproductive glands of Melanoplus sanguinipes

Summary

We have identified a potential nuclear juvenile hormone (JH) receptor in the long hyaline tubules (LHT), part of the male accessory reproductive gland (MARG) of M. sanguinipes. The MARG was incubated in vitro with [³H]JH III, and the distribution of the [³H]JH III among the cellular fractions of the LHT was determined. Some 37±4% of the radioactivity was associated with the crude nuclear pellet, while the cytosolic, microsomal and mitochondrial fractions contained 30±3%, 23±2% and 10±1%, respectively. The bound JH III was measured in nuclear extracts of LHT from males up to 15 days post-eclosion. These results revealed that JH binding increased in an age-dependent manner up to day 7, then levelled off to day 12, to increase again on day 14. The nuclear-binding component in the LHT had a very strong affinity for JH III, with a K_D value of 0.8 nM. Our observations are considered in relation to the potential site and mode of action of JH.     

Coccidia (Protozoa: Eimeridae) of the Herbivorous Mole-Rat, Spalax leucodon Nordmann

SYNOPSIS. A survey of 96 herbivorous mole-rats, Spalax leucodon Nordmann, in Lalahan district of Ankara, Turkey, revealed the presence of 6 new species of coccidia. The species found, the shape and average length-width dimensions (in micrometers) of their oocysts, and the numbers of animals from which they were isolated were as follow: Eimeria lalahanensis sp. n., subspherical to ellipsoidal (20.3 × 12.5), from 10; Eimeria tuzdili sp. n., spherical to subspherical with radially striated oocyst wall, (20.5 × 16.5), from 3; Eimeria spalacis sp. n., ellipsoidal to cylindrical (16.3 × 9.8), from 90; Eimeria elliptica sp. n., ellipsoidal (14.3 × 10.1), from 8; Eimeria turkmenica sp. n., ellipsoidal (11.3 × 8.9), from 1; Isospora anatolicum sp. n., spherical (7.6 × 5.1), from 1 animal. The overall infection rate for 96 examined herbivorous mole-rats was 100%.     

Evidences of the extraglandular origin of two secretory proteins in the male accessory reproductive glands of Chilo partellus (Pyralidae,Lepidoptera, Insecta)

Summary

The male accessory reproductive glands (MARG) play an important role in contributing proteins for the formation of the spermatophore, a structure that transports sperm from the male to the female. Several studies have shown that these proteins could be either of intraglandular or extraglandular origin. SDS-PAGE analysis revealed proteins in the adult MARG of Chilo partellus, which comigrate with the larval hemolymph proteins (LHP). Ouchterlony's immunodiffusion showed that the antiserum raised against MARG extract cross-reacts with the proteins present in the adult hemolymph and fat body. Immunoprecipitates of labelled hemolymph proteins with anti-LHP or anti-MARG proteins reveal two polypeptides that comigrate with LHPs. Thus, there appear to be some proteins of extraglandular origin in the MARG of C. partellus, and the LHP could belong to this category.     

The efficiency of visual assessment for yield and its components in winter oat rows

The efficiency of visual assessment of grain yield and yield components in 0–75 m rows of winter oats was, in general, moderately high. Only eight or less lines were needed to be saved in six out of eight cases to retain at least 50% of the best four lines from the set of 40 lines. Assessments of yield/row and tillers/row were more effective than assessments of grains/panicle and 1000-grain weight on the basis of the proportion of variation accounted for by regression of visual assessment on actual performance. An experienced oat breeder was more successful in his assessment than another assessor unfamiliar with the crop. Assessments of yield/row by the experienced assessor were apparently biased towards assessments of grains/row as the single most easily assessed character, while the assessor unfamiliar with the crop attempted to take tillers/row and 1000-grain weight into account in his assessments. Implications to a winter oat breeding programme are indicated.     

The efficiency of visual assessment of grain yield and its components in spring barley rows

The efficiency of visual assessment for grain yield and its components in spring barley rows was examined using a number of assessors. In 20 out of 28 combinations of assessor and character, only 20 or less lines were needed to be retained from the set of 99 lines to save at least 50% of the best 10 lines. Assessments of tillers/row and to a lesser extent 1000-grain weight were generally more effective than assessments of yield/row and grain/ear. The low effectiveness of assessment of grains/ear was attributed to inadequate sampling of ears. Four out of five assessors showed bias towards assessment of tillers/row, the most easily assessed character, in their assessments of yield/row. Experienced barley workers were more successful in their assessments than others less familiar with the crop. Specially developed keys, aimed at making visual assessment more objective, generally had only small positive effects on the efficiency of assessment. Repeated assessments of characters by some assessors were consistent. It was concluded that visual assessment rather than direct measurement should be recognised as a basic tool of breeding in the early generations, using a large number of lines as a ‘safety net’ allowing the loss of some of the best lines.