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To understand the influence of salt content in soil on the photosynthetic physiological indexes of spring wheat with trickle irrigation, the changes of the photosynthetic physiological indexes of spring wheat and the stomatal limitation and non-stomatal limitation features of photosynthesis were analyzed so as to provide theoretical basis and technical support for spring wheat cultivation in salinealkali soils with trickle irrigation. Pot experiment was conducted to investigate changes of the photosynthetic characteristics of spring wheat under different salt contents in soil (0.15 % (CK), 0.80 %, 1.70 %, and 2.60 %). The results showed that under different conditions of salt content, the daily variations of photosynthetic physiological indexes were similar, and the "noon nap" phenomenon during photosynthesis was obvious. Leaf stomatal conductance of spring wheat was suppressed by the salts in soil, resulting in the decreases of net photosynthetic rate, water utilization efficiency and solar energy utilization efficiency; leaf photosynthesis of spring wheat was restrained by the simultaneous existing of stomatal and nonstomatal factors; decrease of the net photosynthetic rate was mainly caused by stomatal factors under low salt content conditions and by non-stomatal factors under high salt content conditions. The spring wheat leaves had relatively high net photosynthetic rates in soils with initial salt contents of 0.15 % and 0.80 %. According to the results from this study, it is preliminarily concluded that spring wheat with trickle irrigation can be planted in saline-alkali soils with salt content lower than mild salinization soil. Keywords: Trickle irrigation; Spring wheat; Salt content in soil; Photosynthetic characteristics; Stomatal and non-stomatal factor The ability of endophytes to grow in plant tissues is poorly understood as the plant-endophyte association is a complex interaction. It has been hypothesized that poor endophyte growth in plant tissues may consequently result in inferior colonization and expression of antifungal activities. It is pertinent that the growth of the various endophytes (fast-and slow-growing endophytes) are studied in planta, particularly when fast-and slow-growing endophytes competitively exclude pathogens and produce strong antifungal compounds, respectively. In this study, plantlets were first inoculated with fastgrowing endophytes (Trichoderma asperellum T2, Diaporthe phaseolorum WAA02) and slow-growing endophytes (Penicillium citrinum BTF08, Ganoderma boninense or Gb). Their growth in planta was determined based on ergosterol extraction (microwave-assisted extraction method) and quantified with HPLC. Results revealed that slow-growing endophyte BTF08 is naturally richer in ergosterol (66.4 μg per 2 g biomass) compared to fast-growing endophytes (WAA02 and T2 with 13.4 and 39.3 μg per 2 g biomass, respectively). Unlike BTF08, Gb (22.6 μg per 2 g biomass) has lesser ergosterol, suggesting that sporulation may be another factor contributing to ergosterol content. In plants...

Background Cashew is a widely attractive food in the world with high nutritional value for human health. The quality of cashew is closely associated with the flower coloration. However, the underlying mechanism of flower coloration of cashew was poorly understood. Here, we identified two cashew cultivars with variable flower coloration. Then, integrated analysis of metabolome and transcriptome was performed to explore the potential mechanisms. Results The results showed that 8 flavonoid compounds were markedly accumulated in red flower cashew, including taxifolin, procyanidin B2, delphinidin-3-O-glucoside, peonidin-3-glucoside, L-epicatechin, chalconaringenin, luteolin, naringenin and chrysin. In particular, delphinidin-3-O-glucoside, peonidin-3-glucoside and procyanidin B2 were key metabolites that promoted the formation of red flower coloration. Transcriptome analysis revealed that genes involved in flavonoid biosynthesis were also varied among these two cultivars. The flavonoid biosynthesis direction was reprogrammed to synthesize delphinidin-3-O-glucoside, peonidin-3-glucoside and procyanidin B2. Typically, four core genes encoding anthocyanin synthesis were also highly expressed in cashew with red flower, including CFI (TRINITY_DN4346_c0_g1), CHS2 (TRINITY_DN16129_c0_g1), CHS1 (TRINITY_DN2623_c0_g1) and F3H (TRINITY_DN8780_c0_g1). Conclusions This study sheds light on flavonoid metabolic pathways and candidate genes varied in two cashew cultivars and lays a foundation for the breeding programs of cashew.