Multi-decadal trends in large-bodied fish populations in the New South Wales Murray-Darling Basin, Australia

Context: Native fish populations in Australia's Murray-Darling Basin (MDB) have experienced severe declines since European settlement. Information on their status is needed to guide management and recovery. Aims: To quantify trends in MDB fish populations in New South Wales (NSW) from 1994 to 2022. Methods: Relative abundance, biomass, and size structure were examined using generalised additive mixed models at NSW MDB and river catchment (valley) scales for five native species (Murray cod, Maccullochella peelii, golden perch, Macquaria ambigua, silver perch, Bidyanus bidyanus, Macquarie perch, Macquaria australasica, freshwater catfish, Tandanus tandanus) and one alien species (common carp, Cyprinus carpio). Key results: There was strong inter-annual variation in relative abundance, biomass and population structure for all species. At the Basin scale, relative abundance of Murray cod, golden perch and common carp increased across the time series, with no clear trends for silver perch, Macquarie perch or freshwater catfish. Patterns in relative abundance, biomass, and population structure were variable among valleys for most species. Conclusions and implications: Although native fish populations in the MDB remain degraded and face escalating threats, recent increases in the abundance of some native species are an encouraging sign that integrated restoration efforts can improve the outlook for native fish

Floristic homogeneity underlies environmental diversification of northern New Zealand urban areas

<div><p>Urban areas are an important conduit for alien invaders. A floristic study was made of the spontaneously occurring plant species of 11 towns in the lower North Island. Four hundred and eighty-three species were found, from 93 families. <i>Viola sepincula</i> and <i>Sarcococca ruscifolia</i> are recorded as naturalised for the first time. Only <i>Poa annua</i> occurred in > 50% of plots. The majority of species originated from Eurasia and the Mediterranean, having arrived accidentally. A third are annuals and 89% are exotics. Basically homogenous, small floristic differences between towns appear to be related to either chance invasion events or to the environment. Influential environmental factors include the distance to the coast and the size of the central business district. The inland tourist town of Taupo is the most extreme, separated from warmer, coastal, more isolated towns, and from larger, more developed centres. The underlying homogeneity of New Zealand urban floras appears to be due to their recent and relatively uniform history of colonisation and urbanisation.</p></div

Resistance to Meloidogyne incognita, Meloidogyne javanica and Pratylenchus brachyurus in sunflower cultivars adapted to the tropical region of Brazil.

The continuous soybean-maize crop succession in the tropical region of Brazil has led to significant increases in the population size of root-knot (Meloidogyne incognita and M. javanica ) and root-lesion nematodes (Pratylenchus brachyurus), which make soils unsuitable for soybean cropping. A greenhouse study was conducted to identify sunflower genotypes adapted to the tropical region of Brazil and that are resistant to M. incognita, M. javanica and/or P. brachyurus . Two experiments for each nematode were conducted in a completely randomized design with six replicates. Gall index was calculated from visual scores (0?5) of gall intensity on roots for the root-knot nematode. Initial and final population density and reproduction factor were also measured for each nematode. Sunflower genotypes varied in resistance to the nematodes. Sunflower hybrids BRS 321 and BRS 323 were resistant to M. javanica and P. brachyurus and exhibited low gall index for M. incognita . The cultivars are good alternatives to using in the succession of soybean in nematode-infested areas of the tropical regions of Brazil. No sunflower genotype was identified as resistant to M. incognita and thus sunflower cropping is not indicated in areas infested with this nematode

Nematofauna associada à cultura do quiabo na região leste de Minas Gerais The influence of parasitic nematodes on okra crop in eastern Minas Gerais State, Brazil

A cultura do quiabo possui importância sócio-cultural para o estado de Minas Gerais (MG) e 34,2% do volume de quiabo comercializado na Ceasa/Contagem procede dos municípios localizados entre Caratinga e Governador Valadares. Entretanto, o quiabeiro tem a sua produção influenciada pelos danos decorrentes de infecções causadas pelos nematóides das galhas (Meloidogyne spp.). As principais espécies desse nematóide que atacam o quiabeiro já foram relatadas no Brasil, e algumas destas podem causar a morte da planta. A correta identificação da(s) espécie(s) e, ou da(s) raça(s) de Meloidogyne presente(s) nas raízes do quiabeiro é importante na escolha da medida de controle mais apropriada. Para determinar a ocorrência e distribuição de Meloidogyne spp. e outros nematóides na região leste de MG, 70 amostras de solo e raízes da cultura, provenientes de 14 localidades, foram avaliadas por características morfológicas e isoenzimáticas. Dentre as populações de Meloidogyne spp. identificadas prevaleceu M. incognita (fenótipos de Esterase I1 e I2), seguida de M. javanica (fenótipos J2 e J3) e M. arenaria (fenótipo A2). A espécie M. mayaguensis foi confirmada pela ocorrência do fenótipo M2 para esterase, N3 para malato desidrogenase, N2 para superóxido dismutase e N3 para glutamato-oxaloacetato transaminase. Este é o primeiro relato da ocorrência de M. mayaguensis em MG. Outros nematóides detectados na rizosfera do quiabeiro foram Aphelenchus sp., Criconemella sp., Helicotylenchus spp., Pratylenchus brachyurus e P. coffeae, Rotylenchulus reniformis, Rotylenchus sp., Tylenchus sp. e Tylenchorhynchus sp.<br>Okra has a cultural and social importance for the State of Minas Gerais (MG), and 34,2% of the volume marketed in the Ceasa/Contagem, MG, come from the municipalities located near Caratinga and Governador Valadares. The okra production is influenced for the infection caused by the root-knot nematodes (Meloidogyne spp.). The main species of these nematodes attacking okra have already been reported in Brazil, and some of them can cause plant death. The correct identification of Meloidogyne species and, or races infecting okra roots is mandatory for choosing appropriate control measures. To determine the occurrence and distribution of Meloidogyne spp. and other nematodes in the area of the East of MG, 70 soil and root samples coming from 14 municipalities were appraised for morphological and isoenzymatic characteristics. Among the populations of Meloidogyne spp., M. incognita (Esterase phenotypes I1 and I2) prevailed and were followed by M. javanica (phenotypes J2 and J3) and M. arenaria (phenotypes A2). The species M. mayaguensis was confirmed by the phenotypes: esterase (M2), malate dehydrogenase (N3), superoxide dismutase (N2) and glutamate oxaloacetate transaminase (N3). This is the first report of the M. mayaguensis occurrence in MG. Other nematodes associated with the okra plants were Aphelenchus sp., Criconemella sp., Helicotylenchus spp., Pratylenchus brachyurus and P. coffeae, Rotylenchulus reniformis, Rotylenchus sp., Tylenchus sp. and Tylenchorhynchus sp