No abstract

Growth and yield increases, obtained in nodulated soybeans growing in unamended sterile soil by inoculation with the vesicular–arbuscular (VA) mycorrhizal fungus Glomus mosseae, were accompanied by improved P uptake, lower root to shoot ratios, better nodulation with higher nitrogenase activity, and modifications in the pattern of the latter during plant growth. Stimulation of nitrogenase activity occurred early in plant development and preceded plant growth responses by about 2 weeks. Phosphate fertilization increased yield, percent P but not percent N of both mycorrhizal and nonmycorrhizal soybeans, and also modified the pattern and amount of nitrogenase activity during plant growth. Additions of 0.25 g KH2PO4/kg to the soil eliminated the mycorrhizal effect on plant growth, but nodule formation and nitrogenase activity were still significantly stimulated by the mycorrhizal infection. Mycorrhizal effects on nodulation were eliminated with 0.5 g KH2PO4 and on nitrogenase activity with the addition of 1.0 g KH2PO4. These higher levels of phosphate fertilization considerably diminished infection and, in particular, fungal spread within the roots.

SummaryThe impact of noodle processing, storage and cooking on the total phenol content (TPC) and total flavonoid content (TFC) was assessed. Total phenol content (TPC) and total flavonoid content (TFC) of mixed flour were 77.50 and 39.56 mg per 100 g, respectively, and it decreased to 71.80 and 36.30 mg per 100 g after noodle processing. For the fresh Qingke barley noodles (FQBNs), stored at 25 °C, both TPC and TFC decreased significantly during storage. After cooking the fresh noodles, the TPC of the noodles stored for 0 and 4 h increased, while it decreased for the noodles stored for 8, 16 and 24 h; the TFC of all cooked Qingke barley noodles (CQBNs) decreased. Compared with the flour, the DPPH•, ABTS•+, HO• and scavenging ability and ferric reducing antioxidant power (FRAP) decreased significantly (P < 0.05) after noodle processing. For FQBN, increased storage time led to a reduction in antioxidant ability. After cooking, the DPPH• and HO• scavenging ability and FRAP of noodles stored at 25 °C for 0 and 4 h, and the ABTS•+ and scavenging ability of noodles stored at 25 °C for 0, 4 and 8 h increased. Overall, noodle processing, storage and cooking will affect the phenolic compound content and antioxidant activities of barley noodles. Although the shelf life of FQBN is 17 h at 25 °C, from the perspective of nutrition, it is not suitable for long‐term storage, and it is best choice to consume it within the first 4 h.

Summary Microbial diversity and volatile compounds in Qingke barley fresh noodles (QBFN) with different storage time at 25 ± 1 °C were investigated. The results showed that Pseudomonas, Pantoea, Erwinia and Alternaria, Pyrenophora, Penicillium were the dominant microorganisms in edible QBFN (stored for 0 and 12 h), while Pantoea, Erwinia, Bacillus and Penicillium, Aspergillus were the dominant spoilage microorganisms in deteriorated QBFN (stored for 18 h). The edible QBFN have high concentration of aldehydes (61.27 μg kg−1), furan and pyrazines (60.87 μg kg−1), alcohols (49.74 μg kg−1) and ketones (29.74 μg kg−1) that give basic flavours to the QBFN. As storage time increased, the concentrations of above volatile compounds decreased, and new esters and sulphuric compounds which gave unpleasant odours to the QBFN appeared. Multivariate data analysis methods showed that 2‐pentyl‐furan, hexanal, 5‐Ethylcyclopent‐1‐enecarboxaldehy, cyclohexanol and methyl allyl sulphide, ethyl isovalerate were the main volatile compounds that make a difference in flavour between the edible and deteriorated QBFN.

Background and objectives Eating quality is an important quality index of rice, which also determines production and sales. However, previous rice breeding mainly took yield as the gold index, and almost no comprehensive consideration of its eating quality. In this study, to further select new high‐quality japonica rice variety, the eating quality differences in the physicochemical, texture, pasting properties, and volatile compounds between five newly bred varieties (JR5, JR6, JR8, JR9, and JR10) and one commercial variety (Kenyu38) were analyzed. Findings Correlation analysis results indicated that the taste value was negatively correlated with protein (r = −.953, p < .01), amylose content (r = −.915, p < .05), and setback value (r = −.902, p < .05). JR5 had a better appearance and taste quality with significantly lower protein content, amylose content, pasting temperature, and setback value. Moreover, the electronic nose could clearly distinguish JR5 from other rice samples. Aroma analysis showed that JR5 had the significantly higher content of 1‐octene‐3‐ol and hexanal, which were important odor‐active volatile compound in cooked rice. Conclusions JR5 had better eating quality than Kenyu38 and could be used as an excellent variety for further popularization. Significance and novelty This study provides a new perspective for the selection of high‐quality rice varieties.