Wheat scab caused by F. graminearum is a highly destructive disease that leads to yield reduction and mycotoxin contamination of grains. In this study, an endophytic bacterium of strain YB-130 was isolated from surface sterilized wheat spikes with scab symptoms and identified as Bacillus velezensis by whole genome annotation, 16S rRNA gene and average nucleotide identities analysis. The whole-genome sequence of strain YB-130 was obtained by PacBio sequencing. 88 putative Carbohydrate-Active Enzymes and 12 gene clusters encoding for secondary metabolites were identified in the YB-130 genome, including one gene cluster for the synthesis of lanthipeptide only found in strain YB-130 genome. In dual cultures, strain YB-130 significantly inhibited the growth of F. graminearum PH-1 and other eight fungal plant pathogens, indicating a broad antifungal activity. Furthermore, strain YB-130 was able to significantly inhibit spore morphology and hyphal development of F. graminearum PH-1. Strain YB-130 also reduced deoxynivalenol production by F. graminearum PH-1 in dual cultures, possibly due to its ability to suppress the expression of tri5, tri3, and tri8 that are required for deoxynivalenol production in F. graminearum. Overall, B. velezensis YB-130 is a promising biological control agent of both F. graminearum infection and mycotoxin production.

The effects of periods of drought during different phases of reproductive growth of faba bean (Vicia faba L.) cv. Xichang Dabai were investigated in a pot experiment at Xichang Agricultural College, China. Parameters were total dry matter; seed yield; yield components; concentrations of nitrogen, phosphorus, and potassium; and total uptake in different organs. All drought treatments decreased total dry matter production and seed yield per plant. Plants subjected to drought from initiation of pod-set to full pod-set (stage D4) produced 32% less total dry matter and 45% less seed yield than the irrigated control. Mean seed weight was a relatively stable yield component. Statistical analysis indicated that only plants subjected to drought at stages D4 and D5 (drought from full pod-set to maturity) had a significantly (P < 0·05) lower mean seed weight than the control. The nutrient concentration was generally high in the younger or more active organs of faba bean, and comparing the nutrients, the N concentration in leaves, stems, flowers, pods, and grain was greatest, followed by K concentration, and P concentration was least. All soil drought treatments decreased the nutrient concentration in various organs after 17–19 days of drought. However, the decreases at maturity were less clear, except the nutrient concentrations in stems and leaves. Water deficit significantly decreased total grain nutrients per plant, the decreases being 34–45% for N uptake, 34–47% for P uptake, and 33–46% for K uptake. Simple linear correlations with the P and K concentration in leaves at maturity and number of pods and seeds per plant gave a correlation coefficient (r) of 0·804–0·874.

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