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Summary: Legumes such as soybean are considered important crops as they provide proteins and oils for humans and livestock around the world. Different from other crops, leguminous crops accumulate nitrogen (N) for plant growth through symbiotic nitrogen fixation (SNF) in coordination with rhizobia. A number of studies have shown that efficient SNF requires the cooperation of other nutrients, especially phosphorus (P), a nutrient deficient in most soils. During the last decades, great progress has been made in understanding the molecular mechanisms underlying the interactions between SNF and P nutrition, specifically through the identification of transporters involved in P transport to nodules and bacteroids, signal transduction, and regulation of P homeostasis in nodules. These studies revealed a distinct N–P interaction in leguminous crops, which is characterized by specific signaling cross talk between P and SNF. This review aimed to present an updated picture of the cross talk between N fixation and P nutrition in legumes, focusing on soybean as a model crop, and Medicago truncatula and Lotus japonicus as model plants. We also discuss the possibilities for enhancing SNF through improving P nutrition, which are important for high and sustainable production of leguminous crops. [ABSTRACT FROM AUTHOR]

Summary: Legume crops contribute a great portion of clean nitrogen (N) to agro‐ecosystems through symbiotic N2 fixation in the nodule; however, the nodulation is always inhibited by high N availability which is known as the N inhibitory effect through largely unknown mechanisms.We functionally investigated miR169c‐GmNFYA‐C‐GmENOD40 under multiple N conditions in soybean (Glycine max) (ENOD, Early Nodulin; NFYA, Nuclear Factor‐Y Subunit A). We elucidated their regulatory roles in soybean nodulation through analyzing expression patterns, micro–messenger RNA (miRNA–mRNA) interactions, phenotypes of transgenic soybean plants and genetic interactions.We found that miR169c expression was induced by high N, whereas its target GmNFYA‐C was preferentially expressed in nodules and induced by rhizobium inoculation. Overexpression of miR169c inhibited nodulation through targeting 3′‐UTR of GmNFYA‐C, whereas knockout miR169c through CRISPR‐cas9 promoted nodulation. However, overexpression of GmNFYA‐C promoted soybean nodulation through facilitating rhizobium infection and increasing the expression of symbiotic signaling gene GmENOD40. Besides, GmNFYA‐C directly induced the expression of GmENOD40. In addition, overexpression of GmNFYA‐C without the target site of miR169c partially attenuated the inhibitory effect of high N on soybean nodulation.We discovered a new regulatory pathway involving the miR169c‐NFYA‐C‐ENOD40 module that regulates soybean nodulation in response to N availability. This pathway provides substantial new insights into the mechanisms underlying the N inhibitory effect on nodulation. [ABSTRACT FROM AUTHOR]

Maize has the largest cultivation area of any crop in the world and plays an important role in ensuring food security. High-density planting is essential for maintaining high maize yields in modern intensive agriculture. Nonetheless, how high-density planting and the tolerance of individual genotypes to such planting shape the root-associated microbiome of maize is still unknown. In this study, we analyzed the root and rhizosphere bacterial communities of two maize accessions with contrasting shoot architectures grown under high- and low-density planting conditions. Our results suggested that maize hosted specific, distinct bacterial communities in the root endocompartment and that the maize genotype had a significant effect on the selection of specific microbes from the rhizosphere. High-density planting also had significant effects on root-associated bacterial communities. Specifically, genotype and high-density planting coordinated to shape the structure, composition, and function of root and rhizosphere bacterial communities. Taken together, our results provide insights into how aboveground plant architecture and density may alter the belowground bacterial community in root-associated compartments of maize. [ABSTRACT FROM AUTHOR]

The overuse and abuse of antibiotics in animal husbandry is an ongoing problem. While probiotics could be an alternative, their effectiveness, stability and production cost are key factors that need to be addressed first. This study used a mixed culture of Bifidobacterium bifidum, Clostridium butyricum, Bacillus subtilis and Bacillus licheniformis on a simple and inexpensive solid-state medium generated by pouring a liquid MRS medium, which was designed to favor the dense growth of lactobacilli, onto wheat bran at a ratio of 1:2 by weight. Using this method, we achieved a very high number of live bacteria (NLB), at 3.93 × 10 CFU/g, without the need for expensive anaerobic equipment. The mixed culture thus achieved striking results that were up to 10,000 times better than the pure culture and did not require special anaerobic equipment. A real-time PCR analysis demonstrated that the shares of the four strains in the mixed culture probiotics (MCPs) were 2, 17, 46, and 35%, respectively, which indicates that the fermentation product contained an uneven distribution of the four probiotic target bacteria. The MCPs possessed good storage stability at room temperature, and the NLB was greater than 10 CFU/g after 30 days at 25°C, which made it easier to transport and store. They also demonstrated good stability in artificial digestion fluids, with an NLB of over 10 CFU/g after sequential treatments, which enabled them to maintain effectiveness in the animal gastrointestinal tract. Finally, the MCPs were fed to the mealworms ( Tenebrio molitor) and raccoon dogs ( Nyctereutes procyonoides) in order to test their effectiveness, and the growth rates of both significantly improved with the MCPs feeding. This study thus demonstrated that culturing MCPs on a solid-state medium is an efficient method to affordably produce probiotic feed additives that can improve the performance of very physiologically different animals, such as the mealworm and raccoon dog, which indicates their potential for very wide applicability. [ABSTRACT FROM AUTHOR]

Restoration of fish populations is required in China with the use of fishways at dammed rivers, but scant biological data is available for their design and operation. The Changzhou fishway ( CFW) on the Pearl River is the largest in China, providing a channel for multispecies upstream migrations. This preliminary study used a combination of fish traps and hydroacoustic detection to document the diurnal presence of fish in the CFW, with the purpose of providing essential data for a future, solid performance of this fishway. Eighteen species from a total of 1362 fish individuals were collected in the traps. Three species were dominant, namely, Squaliobarbus curriculus, Pseudobagrus vachellii and Cirrhinus molitorella, altogether sharing proportions of 74.70 and 76.26% in the daytime and nighttime, respectively. Balanced by the up-/downward movements of each fish, they entered the fishway with net numbers of 339.9 ± 113.4 ind.h−1, and exited with net numbers of 234.54 ± 26.66 ind.h−1. In diel fishway use, no significant differences were observed in either species composition or individual size during a diurnal period. Fish presence at the monitored sites within the fishway was recorded primarily during the daytime, showing a particular trend towards crepuscular use at the entrance and an uninterrupted use at the exit. This initial study showed a significant fish presence in the CFW during the flood season; the outcome of the study will be the basis of future research aimed at evaluating the passage efficiency of the CFW and the use thereof in other seasons. [ABSTRACT FROM AUTHOR]

Hydraulics play an essential role in successful fish passage through fishways, yet little is known about the response of fish species to specific hydraulic characteristics. This study aims to determine the response of fish presence to water velocity that results from the flow regulation in the Changzhou Fishway (CFW). Water velocity meters and fish traps were used in the study to monitor water velocities and the presence of fish species at flood control levels as well as at normal pool levels. Water velocities in the CFW have a varied significantly as result of flow regulation, whereby water velocities at flood control levels are significantly higher than at normal pool levels (P = 0.014). A total of 3558 fish representing 28 species collected in the CFW were divided into two groups by cluster analysis. This type of divergence in species is strongly associated with the two controlled water levels in the fishway, wherein pelagic species predominate at normal pool levels, and demersal species predominate at flood control levels. This study suggests that the variations in water velocities trigger the shifts in species compositions that in the use of CFW. [ABSTRACT FROM AUTHOR]

Short stature, onychodysplasia, facial dysmorphism and hypotrichosis (SOFT) syndrome is a rare autosomal recessive disease caused by POC1 centriolar protein A (POC1A) pathogenic variants. However, knowledge of genotypic and phenotypic features of SOFT syndrome remain limited as few families have been examined; therefore, the clinical identification of SOFT syndrome remains a challenge. The aim of the present case report was to investigate the genetic cause of this syndrome in a patient with a short stature, unusual facial appearance, skeletal dysplasia and sparse body hair. Giemsa banding and exome sequencing were performed to investigate the genetic background of the family. Spiral computed tomography and magnetic resonance imaging were used for investigating further phenotypic features of the patient. Exome sequencing identified that POC1A had two compound heterozygous variants, namely c.850_851insG and c.593_605delGTGGGACGTGCAT, which, to the best of our knowledge, have not been reported elsewhere. Novel phenotypes were also identified as follows: i) Metaphyseal dysplasia was alleviated (and/or even disappeared) with age; ii) the density of the femoral neck was uneven and the hyperintensity signal of the metaphysis was stripe-like. Thus, the present case report expands the knowledge regarding phenotypic and genotypic features of SOFT syndrome. [ABSTRACT FROM AUTHOR]