Two closely related new species of Aprostocetus Westwood (Hymenoptera: Eulophidae: Tetrastichinae) are described as fortuitous parasitoids of invasive gall inducers in two other genera of Tetrastichinae, Leptocybe

Endoclita signifier Walker (Lepidoptera: Hepialidae) has become a new wood borer pest in Eucalyptus plantations in southern China. This article documents survey results of its geographic distribution and host plant range in Guangxi and its morphological measurements, life cycle and behavior. In total, 83 Eucalyptus growing counties were surveyed. E. signifier was found in 59 counties. Host plants included 31 species in 16 families and 24 genera. Four Eucalyptus hybrid species were recorded as its host plant with E. grandis x E. urophylla and E. urophylla x E. grandis infested the heaviest. The infestation of Eucalyptus trees 1-2 yr old was heavier than that of older trees. Most individuals of E. signifier took 1 yr to complete a generation, overwintering as larvae in tunnels in wooden stems, and pupating in February of the following year. Adults emerge, mate, and lay eggs in April, and the eggs hatch in late April or early May. Adult emergence peaks between 17:00-18:59 hours. Mating flights last under 30 min at dusk and the copulation duration was 24 h. Moths were large, weighting and average of 3.4 g. Eggs and newly hatched larvae were very small, weighing only 0.127 +/- 0.001 mg and 0.093 +/- 0.017 mg, respectively. The larvae have two distinct development stages. One stage spends 1-2 mo living in the forest litter, the second stage then moves to woody stems where it feeds for approximately 10 mo. Larvae start boring into hosts between June and November, mainly in July and August. This study indicated that E. signifier, a highly polyphagous native species, has shifted host to exotic Eucalyptus and can cause significant damage to plantations.

Buzura suppressaria Guenee (Lepidoptera: Geometridae) is a defoliator that seriously harms eucalyptus trees in South China. Buzura suppressaria nuclear polyhedrosis virus (BsNPV) is a baculovirus that infects B. suppressaria with high specificity and efficiency. Transcriptomes of B. suppressaria were sequenced before and after BsNPV infection using an Illumina-based platform to probe for differentially expressed genes (DEGs) of B. suppressaria after viral infection. On average, ∼57.4 million high-quality clean reads were generated and assembled de novo into 69,761 unigenes. The NCBI nonredundant protein, Swiss-Prot, Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene ontology (GO), and Cluster of Orthologous Groups databases were used to annotate unigenes through NCBI BLAST; 33,575 unigenes (48.1%) were then mapped to at least one of these databases, and 4,366 unigenes (6.3%) were mapped to all databases. Differential expression analysis showed that 25,212 unigenes were upregulated and 22,880 unigenes were downregulated in at least one pairwise comparison. Control versus 48 h had more DEGs than other two pairwise comparisons in either the GO or KEGG database, because the number of regulated gene would increase as BsNPV infected more tissues and would decrease as more tissues were disabled. To ascertain B. suppressaria immune response to BsNPV infection, DEGs were annotated to the GO and KEGG databases. In total, 89 GO categories are related to immune response and 1,007 DEGs are annotated to these GO categories. Furthermore, 7 downregulated DEGs and 37 upregulated were obtained simultaneously in all three groups. These DEGs were considered to possess a central role throughout viral infection.

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Eucalyptus grandis × Eucalyptus urophylla hybrid clone is an economically and ecologically important forest variety and is widely planted in Guangxi, China. Black spot, a newly found disease, occurred nearly 5333.3 hectares in an E. grandis × E. urophylla plantation of Qinlian forest farm (N: 21.866°, E: 108.921°) in Guangxi in October, 2019. Infected plants had lesions of black spots with watery margins on petioles and veins of E. grandis × E. urophylla. The size of spots ranged between 3 to 5 mm in diameter. When lesions expanded to girdle the petioles, wilt and death of leaves was observed, which subsequently affected growth of the trees. To isolate the causal agent, symptomatic plant tissues (leaves and petioles) were collected from two different sites, sampled from five plants each site. In the lab, infected tissues were surface sterilized with 75% ethanol for 10 seconds, then 2% sodium hypochlorite for 120 seconds, and rinsed with sterile distilled water three times. Small segments (5×5 mm) were cut from the margins of the lesions, then placed on potato dextrose agar (PDA) plates. The plates were incubated at 26°C in dark for 7 to 10 days. Fungal isolates YJ1 and YM6 with a similar morphology, which were obtained from 14 of 60 petioles and 19 of 60 veins respectively. These two colonies were initially light orange, then turned to olive brown as time progressed. Conidia were hyaline, smooth, aseptate, ellipsoidal, apex obtuse, and base tapering to flat protruding scar, 16.8 to 26.5µm long, and 6.6 to 10.4 µm wide (n=50). Some conidia had one or two guttules. The morphological characteristics were consistent with the description of Pseudoplagiostoma eucalypti Cheew., M. J. Wingf. & Crous (Cheewangkoon et al. 2010). For molecular identification, the internal transcribed spacer (ITS), β-tubulin (TUB2) genes were amplified using primers ITS1/ITS4 and T1/Bt2b, respectively (White et al. 1990; O'Donnell et al.1998; Glass and Donaldson 1995). Sequences of the two strains were deposited in GenBank (ITS: MT801070 and MT801071; BT2: MT829072 and MT829073). Phylogenetic tree was constructed with a maximum likelihood method, revealing that YJ1 and YM6 were on the same branch with P. eucalypti. Pathogenicity tests of the two strains were performed on three-month-old E. grandis × E. urophylla seedlings, by inoculating 6 wounded (by stabbing on petioles or veins) leaves of seedlings with mycelial PDA plugs (5 ×5 mm) from the edge of a 10-day old colony of strain YJ1 or YM6. Another 6 leaves were treated in the same manner but with PDA plugs as controls. All treatments were incubated in humidity chambers at 27°C and 80% relative humidity, under ambient light. All experiments were conducted three times. Lesions were observed at the points of inoculation, the petioles or veins turned black on inoculated leaves after 7 days, wilting of the leaves were also observed after 30 days, however the controls remained asymptomatic. Re-isolation was made and the fungus had same morphological measurements as the inoculated fungus, thus completing Koch's postulates. P. eucalypti had been reported as a pathogen of leaf spot on E. robusta in Taiwan island (Wang et al. 2016), leaf and shoot blight on E. pulverulenta in Japan (Inuma et al. 2015). To our knowledge, this is the first report of P. eucalypti affecting E. grandis × E. urophylla in mainland China. This report provides basis for the rational prevention and control of this new disease in the cultivation process of E. grandis × E. urophylla.