Bioindicator potential of Spathosternum prasiniferum prasiniferum (Orthoptera; Acridoidea) in pesticide (azadirachtin)-induced radical toxicity in gonadal/nymphal tissues; correlation with eco-sustainability

Acridids are highly abundant living-organism/major-component in agricultural field, globally. It may act as a dependable bio-indicator species in response to environmental-stress. Antioxidants protect insects by scavenging free radicals. Here, we investigated the dose dependant azadirachtin (C₃₅H₄₄O₁₆ AZT) toxicity on oxidative-biomarker; Alkaline-phosphatase (ALP), malondialdehyde (MDA), non-protein-soluble-thiol (NPSH) and antioxidants like superoxide-dismutase (SOD), catalase (CAT), glutathione-peroxidase (GPx) and amylase of gonads from both sexes and juvenile tissues of common grasshopper, Spathosternum prasiniferum prasiniferum (Walker, 1871). The newly hatched adults (female: male = 1:1) are exposed to 1 to 20 ppm AZT for 48 h and have compared to control and 6 h incubation with same concentration of azadirachtin for in vitro experiments. Both in vivo and in vitro experiment demonstrated significant influences on oxidative biomarkers with increasing antioxidant enzymatic activities in either sex. The male gonads represents decreasing antioxidant enzyme activities compared to female gonads. Lesser protection by CAT and SOD are noticed in male than female in response to AZT exposure. This experiment suggests that azadirachtin increased the major biomarkers with decreasing antioxidant enzyme activities resulting in more free-radicals related threat in adult male gonads. Variable dose responses were noticed on ALP, AchE and MDA in either gender suggesting multiphasic action of the pesticides. Higher mortality rate is noticed in male with lower nymphal life span. Moreover, nymph II^nd is more susceptible than nymph IV^th in vitro intoxication of azadirachtin. Possible life threat of vast representatives of agricultural ecosystem by pesticide should be avoided to maintain different bio-geo cycle and eco-sustainability.     

New species of the pleasing lacewing genus Dilar Rambur, 1838 (Neuroptera,Dilaridae) from the Hengduan Mountains,southwestern China

The genus Dilar Rambur, 1838 (Neuroptera, Dilaridae) is the most species-rich genus of the family Dilaridae and is diverse in China, previously with 32 described species. Here we report two new species of Dilar from the southern part of the Hengduan Mountains, Sichuan, southwestern China, namely Dilar muliensis sp. nov. and Dilar punctulosus sp. nov. A revised key to species of Dilar from China is provided.www.zoobank.org/urn:lsid:zoobank.org:pub:27EC214B-6587-4E38-BDAC-295F7389ABF3.     

Genetic diversity and geographic distribution of Bemisia tabaci species complex in Nepal

Bemisia tabaci species complex comprises at least 44 cryptic species worldwide. Here, we analyze the nucleotide sequences of mitochondrial cytochrome oxidase subunit 1 (COI) gene obtained from 76 samples of B. tabaci collected from 23 districts in Nepal. This is the first genetic and geographic study of B. tabaci species complex in Nepal. Our phylogenetic study identified the presence of three cryptic species—Asia I, Asia II 1, and Asia II 5—with high interspecific but low intraspecific variations. Among the three cryptic species, Asia II 5 was the most prevalent in Nepal, constituting 64.47% of all the sequenced samples. Based on haplotype network analysis of COI sequences, Asia II 1 was more genetically diversified than the other two cryptic species. Our results provided useful information on the genetic diversity and geographic distribution of B. tabaci in Nepal, which help monitor population changes of B. tabaci at cryptic species level and develop sustainable management strategies for its control.     

Genetic diversity of Bemisia tabaci cryptic species in Nigeria and their relationships with endosymbionts and acquired begomoviruses

Bemisia tabaci is a species complex of at least 44 cryptic species with a worldwide distribution. It is a serious pest of many crop plants as well as a successful vector of at least 100 begomoviruses. Using B. tabaci collected from cassava and tomato fields in the southwestern and north central regions of Nigeria, we determined nucleotide sequences from the mitochondrial cytochrome c oxidase subunit I (COI) of 23 B. tabaci samples, the 16S and 23S ribosomal DNA of endosymbionts, and the coat protein gene of geminiviruses ingested by the whiteflies. The COI analysis identified three different genetic groups including the indigenous Sub-Saharan Africa 1 subgroup 1 (SSA1-SG1) and 5 (SSA1-SG5, which was most prevalent), and an invasive cryptic species (Mediterranean). SSA1 was infected by five known secondary endosymbionts, Arsenophonus, Cardinium, Hamiltonella, Rickettsia, and Wolbachia, and co-infections with two or three endosymbionts were common. Five begomoviruses, okra enation leaf curl virus, squash leaf curl China virus, tobacco curly shoot virus, tomato leaf curl New Delhi virus, and tomato yellow leaf curl virus, were detected from 43.5% of the B. tabaci samples. However, cassava mosaic disease that causes devastating cassava yield losses was not detected in this study. This study improves the current understanding of the genetic diversity of B. tabaci cryptic species, and it reveals their relationships with endosymbionts and geminiviruses in the cassava and tomato fields of Nigeria.     

Integrating management techniques to restore subtropical forests invaded by Hedychium coronarium J. Köenig (Zingiberaceae) in a biodiversity hotspot

The restoration of areas invaded by non‐native plants is challenging as invasive plants may affect both biotic and abiotic components of ecosystems, leading to impacts that constrain recolonization by native species after invaders are eliminated. In such a scenario, restoration techniques as topsoil transposition might accelerate colonization by native species in forests. Hedychium coronarium J. Koenig (Zingiberaceae) is a Himalayan herbaceous rhizomatous plant recognized as invasive in several countries. This study aimed to experimentally evaluate the response of plant assemblages to topsoil transposition on a site invaded by H. coronarium after chemical control. Four treatments were applied: chemical control integrated with topsoil transposition, chemical control of H. coronarium alone, topsoil transposition alone, and no intervention (control). Plots were evaluated prior to the application of treatments and then monthly for 11 months after treatments. Parameters were measured for H. coronarium (number of ramets, ramet height, and cover) and other species (species richness, abundance, and cover). Plots treated with chemical control (regardless of topsoil transposition) were similar in terms of all parameters measured and species composition, with dominance of herbs and shrubs. Plots managed solely with topsoil transposition had lower species richness, abundance, and cover, but more diverse life‐forms, being equally rich in climbers, trees, and herbs. Chemical control was effective to control invasion by H. coronarium and increase species richness and abundance on the managed site. Topsoil transposition promoted colonization by species that might accelerate restoration.     

The impact of a fox‐ and cat‐free safe haven on the bird fauna of remnant vegetation in southwestern Australia

Introduced predators are a serious threat to Australian vertebrates. However, the consequences of predation for an area's avifauna have rarely been quantified. We took advantage of the establishment of a 7,832 ha fox‐ and cat‐free safe haven at Mt Gibson, in Western Australia, to assess the consequences of excluding introduced mammal predators on the bird fauna. Bird surveys were conducted over 6 years, before and after the establishment of the introduced predator‐free safe haven. After 3 years, half the sites were enclosed by the fence that excluded introduced predators, while the remainder of sites remained outside the fence and were exposed to fox and cat activity. The sites were stratified by four major vegetation types. A total of 91 bird species were variously detectable with the survey approach, but were typically more detectable during morning surveys. Site occupancy varied considerably among species, but overall, occupancy by all species was most likely to be either not impacted or positively impacted by the safe haven. The most notable change was that avifaunal richness appeared to increase in woodland and shrubland habitats within, as compared to outside, the safe haven. We conclude that: (1) the safe haven had an overall positive impact on bird occupancy; and (2) there were no consistent trends with respect to the kinds of species whose occupancy was positively impacted, beyond them all being small‐ to medium‐sized birds and mostly insectivorous. However, these conclusions must be tempered by the poor detection probability of many species.     

Shrub influences on seedling performance when restoring the slow‐growing conifer Pilgerodendron uviferum in southern bog forests

Forest restoration is most efficient if it can take advantage of facilitative interactions between established vegetation and planted trees. However, positive and negative interactions have been identified in a number of plant communities. After centuries of anthropogenic fires, forest recovery has been extremely slow in southern bog forests previously dominated by the slow‐growing and vulnerable conifer Pilgerodendron uviferum on Chiloé Island, Chile. Today, the landscape is dominated by secondary shrublands with scattered patches of Sphagnum moss and limited natural tree regeneration. We hypothesized that the retention of secondary shrubs facilitates the early performance of P. uviferum restoration plantings by providing better microsite conditions. To test this hypothesis, we compared the response of seedlings planted on sites prepared at two levels of intervention: after shrubs had been removed or where shrubs were retained. Shrub retention showed a nurse‐plant effect on P. uviferum seedlings 4 years after planting, which resulted in reduced physiological stress (measured as Fv/Fm) for seedlings, as well as reduced browsing. Consequently, the seedlings growing in areas with shrub retention had larger height increment and higher vitality than those in areas where shrubs had been removed. Thus, the more open micro‐site conditions created by shrub removal resulted in generally poorer seedling performance, although seedling mortality—which was low overall (approximately 2–4%)—showed no significant difference between the two levels of intervention. These findings have direct implications for the restoration of slow‐growing conifers that can tolerate extreme wet conditions in highly degraded forests.     

Do soil inoculants accelerate dryland restoration? A simultaneous assessment of biocrusts and mycorrhizal fungi

Biological soil crusts (biocrusts) and arbuscular mycorrhizal (AM) fungi are communities of soil organisms often targeted to assist in the achievement of multiple ecological restoration goals. In drylands, benefits conferred from biocrust and AM fungal inoculation, such as improved native plant establishment and soil stabilization, have primarily been studied separately. However, comparisons between these two types of soil inoculants and investigations into potential synergies between them, particularly at the plant community scale, are needed to inform on‐the‐ground management practices in drylands. We conducted two full‐factorial experiments—one in greenhouse mesocosms and one in field plots—to test the effects of AM fungal inoculation, biocrust inoculation, and their interaction on multiple measures of dryland restoration success. Biocrust inoculation promoted soil stabilization and plant drought tolerance, but had mixed effects on native plant diversity (positive in greenhouse, neutral in field) and productivity (negative in greenhouse, neutral in field). In greenhouse mesocosms, biocrust inoculation reduced plant biomass, which was antagonistic to % root length colonized by AM fungi. Inoculation with native or commercial AM fungi did not influence plant establishment, drought tolerance, or soil stabilization in either study, and few synergistic effects of simultaneous inoculation of AM fungi and biocrusts were observed. These results suggest that, depending on the condition of existing soil communities, inoculation with AM fungi may not be necessary to promote dryland restoration goals, while inoculation with salvaged biocrust inoculation may be beneficial in some contexts.