Transcriptome analysis in Malus halliana roots in response to iron deficiency reveals insight into sugar regulation.[Pubmed: 30101382]

Iron (Fe) deficiency is a frequent nutritional problem limiting apple production in calcareous soils. The utilization of rootstock that is resistant to Fe deficiency is an effective way to solve this problem. Malus halliana is an Fe deficiency-tolerant rootstock; however, few molecular studies have been conducted on M. halliana. In the present work, a transcriptome analysis was combined with qRT-PCR and sugar measurements to investigate Fe deficiency responses in M. halliana roots at 0 h (T1), 12 h (T2) and 72 h (T3) after Fe deficiency stress. Total of 2473, 661, and 776 differentially expressed genes (DEGs) were identified in the pairs of T2 vs. T1, T3 vs. T1, and T3 vs. T2, respectively. Several DEGs were enriched in the photosynthesis, glycolysis and gluconeogenesis, tyrosine metabolism and fatty acid degradation pathways. The glycolysis and photosynthesis pathways were upregulated under Fe deficiency. In this experiment, sucrose accumulated in Fe-deficient roots and leaves. However, the glucose content significantly decreased in the roots, while the fructose content significantly decreased in the leaves. Additionally, 15 genes related to glycolysis and sugar synthesis and sugar transport were selected to validate the accuracy of the transcriptome data by qRT-PCR. Overall, these results indicated that sugar synthesis and metabolism in the roots were affected by Fe deficiency. Sugar regulation is a way by which M. halliana responds to Fe deficiency stress.

Transcriptional and physiological analyses of short-term Iron deficiency response in apple seedlings provide insight into the regulation involved in photosynthesis.[Pubmed: 29902966]

Iron (Fe) is an essential micronutrient for plants. Utilization of Fe deficiency-tolerant rootstock is an effective strategy to prevent Fe deficiency problems in fruit trees production. Malus halliana is an apple rootstock that is resistant to Fe deficiency; however, few molecular studies have been conducted on M. halliana.

Antithrombotic components of Malus halliana Koehne flowers.[Pubmed: 29496530]

Flowers of Malus halliana (M. halliana) Koehne have been used as a Chinese traditional medicine to treat metrorrhagia and in our study, its chemical composition and anticoagulant effect were investigated. Five compounds were isolated and identified from M. halliana flowers, including limocitrin-3-O-glucoside (1), baohuoside Ⅱ (2), kaempferol-3-O-α-L-furan arabinoside (3), phloretin-4'-O-glycosidase (4) and afzeloside (5). Compound 1-3 were isolated for the first time from this genus. The anticoagulant effect of the compounds and extracts of M. halliana flowers were evaluated by APTT, PT, TT and FIB on plasma of rabbit in vitro. The results indicated that several fractions of M. halliana flowers and compounds 2-5 exhibited anticoagulant activity in vitro. Subsequently, afzeloside (5), the abundant component in M. halliana flowers, was investigated further for its antithrombotic effect in vivo and its antithrombotic mechanisms were evaluated on rats acute blood-stasis model. The antithrombotic effect was evaluated by WBV, PV, HCT, ESR, APTT, PT, TT, FIB, 6-keto-PGF1α, TXB2, ET-1 and eNOS in vivo. Afzeloside demonstrated inhibitory effect of thrombus formation, and its underlying antithrombotic mechanism was found to be related to the regulation of vascular endothelium active substance, activating blood flow and anticoagulant effect. Hence, we postulate that flavonoids may be the active ingredients of the plant.

[Simultaneous determination of quercitrin, phloridzin and 3-hydroxyl phloridzin in leaves of Malus halliana by ultrasound-assisted ionic liquid-reversed phase liquid chromatography].[Pubmed: 28901112]

To establish a method for the simultaneous determination of phloridzin, 3-hydroxy phloridzin and quercitrin in leaves of Malus halliana by ultrasonic-assisted ionic liquid coupled with RP-HPLC. An Agilent TC-C₁₈ (4.6 mm×250 mm, 5 μm) column was used, with the mobile phase of acetonitrile and 1% phosphoric acid-water (20∶80) by gradient elution at the detection wavelength of 270 nm. The flow rate was 0.8 mL•min⁻¹, and chromatographic column temperature was controlled at the room temperature. Under the optimized conditions, the linear ranges for phloridzin, 3-hydroxy phloridzin and quercitrin were 0.9-112.5 μg (r = 0.999 6), 0.093 2-11.65 μg (r = 0.999 1) and 0.097 2-12.15 μg (r = 0.999 8), respectively. The average recoveries of the three constituents were 99.35%, 98.80% and 98.19%, respectively. The method was environmental friendly, rapid, accurate and highly reproducible, and so suitable for the quantitative analysis of phloridzin, 3-hydroxy phloridzin and quercitrin in leaves of M. halliana.

Furandiones from an endophytic Aspergillus terreus residing in Malus halliana.[Pubmed: 22971827]

Two new furandiones named asperterone B (1) and C (2) together with four known metabolites (3-6) were isolated from the liquid culture of the endophytic fungus Aspergillus terreus MHL-P22 residing in the fresh leaves of Malus halliana. The structures of the new compounds were elucidated by analysis of their MS, IR, 1D- and 2D-NMR spectra. 1 and 2 showed moderate cytotoxic activities against human colorectal carcinoma SW1116 cells with IC(50) values of 57.5 and 71.0 µM, respectively. The biosynthetic pathway for 1, 2 and their analogues was also postulated and briefly discussed.

Seasonal variation of diet and food availability in a group of Sichuan snub-nosed monkeys in Shennongjia Nature Reserve, China.[Pubmed: 16477596]

We studied the diet and food availability of a group of Sichuan snub-nosed monkeys for 14 months (July 2003 to September 2004, except for February) in the Shennongjia Nature Reserve, China. This species is primarily a lichen eater, with lichens (Usneaceae) accounting for 43.28% of feeding records (n=3,452). Other food types in the diet were young leaves (28.71%), fruits or seeds (14.57%), buds (5.36%), mature leaves (3.51%), herbs (2.09%), bark (1.36%), and flowers (1.13%). The monkeys used 23 plant species. Their diet showed a complicated seasonal variation: the monthly diet varied from primarily lichens in November-April, to a mixture of leaves and lichens in May-July, to a mixture of fruits or seeds and lichens in August-October (the latter depended on annual fruit and seed availability). The proportion of fruits or seeds in the diet was negatively correlated with that of lichens, which suggests that the monkeys prefer fruits or seeds to lichens when all of these items are available. The fruit or seed availability varied greatly between the two study years. The proportion of lichens, young leaves, flowers, and fruits or seeds in the diet was positively associated with their availability. The monkeys appeared to be selective feeders. They preferred 10 tree species for plant parts, and nine tree species for lichens. The selection index of tree species for lichens was positively related to lichen coverage per branch on tree species, demonstrating that the monkeys preferred tree species with abundant lichens, as well as dead trees for lichens. The results suggest that dead-tree harvesting in the reserve could significantly reduce the quality of habitat for these monkeys, and should therefore be prohibited. Connus controversa, Cerasus discadenia, Salix willichiana, and Malus halliana should be conserved as top priority species because the monkeys preferred them for both their vegetative parts and the lichens that grow on them.