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In recent years, the distribution and population of the Xinjiang wild apple, Malus sieversii, a protected vulnerable plant among endangered rare germplasm resources of China, have been decreasing. A field survey conducted during 2015–2017 detected decline and dieback of Xinjiang wild apple in the Yili region in Xinjiang Province. Two Phytophthora spp. were isolated from cankers and soil samples around symptomatic M. sieversii trees: One isolate was shown to cause infection, based on Koch's postulates. The isolate was identified as Phytophthora plurivora based on morphological features, physiological characteristics, ITS1–5.8S–ITS2 rDNA and cox1 sequence analyses. This is the first report of P. plurivora pathogenicity on Xinjiang wild apple in Xinjiang Province in China, constituting a new host for this pathogen. The potential of P. plurivora to cause damage in pure stands of Xinjiang wild apple in Xinjiang Province should be determined.

Greenhouse experiments were conducted to evaluate the impact of "'red mud", the residue of the Bayer process for extracting alumina from bauxite, on wetland to investigate whether red mud can be used for wetland restoration. Two wetland species, Spartina alterni/lora Loisel. and Sagittaria lanci/'olia L., were used to test their response to the following substrate treatments: 100 % marsh sediment, 100 % red mud, a mixture of 50 % marsh sediment and 50 % red mud, a mixture of 50 % red mud and 50 % compost, and neutralized red mud. Each substrate treatment received two fertilization levels, fertilized (N-P-K) and unfertilized. Red mud could support the growth of the salt marsh species, Spartina aherni/lora, but not the fresh marsh species, Sagittaria lancifolia. The high Na content and salinity of red mud, even when mixed with marsh sediment or compost, appeared to be the primary cause for the high mortality of Sagittaria in these substrates. Fertilization did not reduce the stress response of Sagittaria to red mud, but significantly increased the growth of Spartina. Red mud is low in available N and P and required fertilizer or organic matter (e.g., compost) addition to increase fertility. In experiments with both fresh and salt marsh sediments, the concentrations of soluble heavy metals, with the exception of Mn, were not significantly greater for red mud than for marsh sediment. Thus, the release of heavy metals from red mud over the short-term may not pose an environmental concern. However, the mobilization of heavy metals over the long-term and the influence of plants in accumulating metals requires further investigation.

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