A Preliminary Study of the Key Technologies in Rice Seed Production

To study the production technology of rice seeds,with Lianjing 7 as test material,this paper explores the effects of the key rice seed production,processing and storage technologies( such as nitrogen fertilizer application and management,weeding mode in seed breeding field,temperature control of mechanical drying and water control on seed storage) on the quality of rice seeds. The results show that the optimal application proportion of tillering stage dressing and earing fertilizer is 8: 2,followed by 7 : 3; the best time of weeding is booting stage,with the highest purity; the effect of drying and germination rate is best when the temperature is controlled at 44℃ in mechanical drying process; the seed storage quality and storage costs can be guaranteed when the water content of rice seed is controlled at 18%.

Effects of solid-state fermentation product of yeast supplementation on liver and intestinal health,and resistance of common carp(Cyprinus carpio)against spring viraemia carp virus

This study aimed to investigate the effects of solid-state fermentation products of yeast(SFPY)on liver and intestinal health and disease resistance of common carp(Cyprinus carpio).A total of 200 common carp with an initial average weight of 2.55±0.004 g were divided into 5 groups(4 replications per group and 10 fish per replication),and were fed with one of five diets,including a control diet and 4 diets supplemented with 2‰(Y2),3‰(Y3),4‰(Y4),or 5‰(Y5)SFPY,respectively,for 8 weeks.Results indicated that,the addition of SFPY to the diet of common carp did not affect the growth performance or survival rate of fish(P=0.253).Interestingly,with the addition of SFPY,the triacylglycerol(TAG)content of the liver presented a linear decreasing tendency(P=0.004),with significantly decreased in Y4 and Y5 groups(P=0.035)compared with control.Serum lipopolysaccharide(LPS)content and diamine oxidase(DAO)activity presented a negative linear relationship with the addition of SFPY(P=0.015,P=0.030),while serum lipopolysaccharide binding protein(LBP)content first decreased and then increased(P<0.001).The total antioxidant capacity(T-AOC)in the intestine of fish increased continuously with increasing SFPY supplementation(P=0.026),reaching the highest level in Y5 group.The villus height in all experimental groups were significantly higher than that in the control group(P<0.001).Furthermore,compared to the control,adding 3‰SFPY to the control diet of common carp significantly increased the relative abundance of Fusobacteria(P=0.018)and decreased that of Proteobacteria(P=0.039)at phylum level,and increased the relative abundance of Cetobacterium(P=0.018)and decreased that of Shewanella(P=0.013)at genus level.Compared with the control,the relative mRNA expression level of spring viraemia of carp virus N protein(SVCV-n)in the kidney was lower than that of the control group without significance and bottomed out in Y4 group(P=0.138).In conclusion,dietary SFPY enhanced the SVCV resistance capacity of common carp by improving liver and intestinal health and modulating the gut microbiota.Thus,SFPY is a potential feed additive to be used in aquaculture to reduce the huge economic loss of common carp due to SVCV disease.Based on liver TAG content and intestinal villus height,the optimal addition level of SFPY was 3.02‰and 2.72‰,respectively.

Biocontrol agents modulate phyllosphere microbiota interactions against pathogen Pseudomonas syringae

The pathogen Pseudomonas syringae,responsible for a variety of diseases,poses a considerable threat to global crop yields.Emerging biocontrol strategies employ antagonistic microorganisms,utilizing phyllosphere microecology and systemic resistance to combat this disease.However,the interactions between phyllosphere microbial dynamics and the activation of the plant defense system remain poorly understood.Here we show significant alterations in phyllosphere microbiota structure and plant gene expression following the application of biocontrol agents.We reveal enhanced collaboration and integration of Sphingomonas and Methylobacterium within the microbial co-occurrence network.Notably,Sphingomonas inhibits P.syringae by disrupting pathogen chemotaxis and virulence.Additionally,both Sphingomonas and Methylobacterium activate plant defenses by upregulating pathogenesis-related gene expression through abscisic acid,ethylene,jasmonate acid,and salicylic acid signaling pathways.Our results highlighted that biocontrol agents promote plant health,from reconstructing beneficial microbial consortia to enhancing plant immunity.The findings enrich our comprehension of the synergistic interplays between phyllosphere microbiota and plant immunity,offering potential enhancements in biocontrol efficacy for crop protection.

Effects of redox potential on soil cadmium solubility:Insight into microbial community

Understanding the role of microbes in the solubility of cadmium(Cd) is of fundamental importance for remediation of Cd toxicity. The present study aimed to identify the microbes that involved in regulating Cd solubility and to reveal possible mechanisms. Therefore,microbial communities were investigated through high-throughput sequencing approach, the molecular ecological network was constructed and metagenomes were predicted. Our results indicated that redox conditions affected both the solubility of soil Cd and the microbial communities. Anaerobic microbes, such as Anaerolineaceae, did not only play important roles in shaping the microbial community in soils, but might also be involved in regulating the Cd solubility. Two possible mechanisms that how Anaerolineaceae involved in Cd solubility are(1) Anaerolineaceae are important organic matter degraders under anoxic conditions and(2) Anaerolineaceae can co-exist with methane metabolism microbes, while methane metabolism promotes the precipitation of soluble Cd. Thus, application of Anaerolineaceae in bioremediation of soil Cadmium contamination is a potential approach. The study provided a novel insight into the role of microbial community in the regulation of Cd solubility under different redox conditions, and suggested a potential approach for the remediation of soil Cd contamination.

Determining the biological zero for gonadal development razor clams Sinonovacula constricta (lamarck 1818) in Zhejiang,China

The biological zero of gonadal development and the effective accumulated temperature of one and two-year-old razor clams Sinonovacula constricta(Lamarck 1818)were studied in Sanmen County,Zhejiang Province,China between April 2016 to October 2017,using a new variety named“Shen-Zhe No.1”.The biological zero was determined by using the rule of effective accumulated temperature and the linear regression method,which was confirmed using a histological analysis of the full gonadal development cycle.The results showed that the biological zero of gonadal reproduction of 1-year-old and 2-year-old S.constricta was the same:20.8℃.When the temperature reached 20–21℃,analysis of the histological sections indicated that more than half of the S.constricta individuals initiated gonadal development.The average effective accumulated temperature over two years was 806 d℃.This study contributes to our understanding of the regulation and control of gonadal maturation,suggesting that changes in the spawning and breeding season during one-year of farming using the new variety of razor clam could provide an economic benefit to industrialized large-scale spat production.The results demonstrated that the razor clam S.constricta is a typical clam of the accumulative temperature mature oviposition type.In addition,although S.constricta does not display hypothermy,it requires a lower temperature for gonadal maturity and spawning.

Innate endogenous adjuvants prime to desirable immune responses via mucosal routes

Vaccination is an effective strategy to prevent infectious or immune related diseases, which has made remarkable contribution in human history. Recently increasing atten- tions have been paid to mucosal vaccination due to its multiple advantages over conventional ways. Subunit or peptide antigens are more reasonable immunogens for mucosal vaccination than live or attenuated pathogens, however adjuvants are required to augment the immune responses. Many mucosal adjuvants have been developed to prime desirable immune responses to different etiologies. Compared with pathogen derived adjuvants, innate endogenous molecules incorporated into mucosal vaccines demonstrate prominent adjuvanticity and safety. Nowadays, cytokines are broadly used as mucosal adjuvants for participation of signal transduction of immune responses, activation of innate immunity and polarization of adaptive immunity. Desired immune responses are promptly and efficaciously primed on basis of specific interactions between cytokines and corresponding receptors. In addition, some other innate molecules are also identified as potent mucosal adjuvants. This review focuses on innate endogenous mucosal adjuvants, hoping to shed light on the development of mucosal vaccines.