Ripening-related defense proteins in Annona fruit     

Oscar Goñi  María T. Sanchez-Ballesta  Carmen Merodio  María I. Escribano 《Postharvest Biology and Technology》2010,55(3):169-173

In order to obtain a better understanding of the active defense strategy of cherimoya (Annona cherimola Mill.) fruit, hydrolytic and antifungal activity, as well as expression of proteins functionally and immunogenically related to the pathogenesis-related proteins chitinase (PR-Q) and 1,3-β-glucanase (PR-2), were estimated in fruit at different ripening stages. Increase in expression of the 27 kDa constitutive chitinase and the induction of two new proteins, a 26 kDa chitinase and a 51 kDa 1,3-β-glucanase were associated with enhanced in vitro hydrolytic and antifungal activity of the acidic protein extract in ripe fruit. Ripening modified the expression of constitutive basic isoenzymes, with a sharp decrease in both relative accumulation and hydrolytic activity. Likewise, a new basic 33 kDa chitinase was induced in the over-ripe fruit, concomitant with accumulation of a basic constitutive 76 kDa 1,3-β-glucanase. At this stage, the basic protein extract modified in vitro growth inhibition of Botrytis cinerea. Short-term high CO₂ treatment delayed fruit ripening and maintained a similar distribution of activity and isoenzymatic pattern in both protein fractions to that in unripe fruit. These results indicate that the changes in the pattern of defense proteins and hydrolytic activity in cherimoyas appear to be associated with ripening. Moreover, unlike the constitutively expressed isoenzymes, only the transitorily induced chitinases and 1,3-β-glucanases were associated with an active defense-related response.  相似文献   

Comparative Studies on Corynebacter1Um Pyogenes Toxin Formation in Monocultures and Mixed Cultures: The Demonstration of a Stimulating Effect of Peptococcus Indolicus and Stuart-Schwan Cocci     

Gunner Hi Srensen 《Acta veterinaria Scandinavica》1980,21(3):438

The growth and the toxin (i.e. hemolysin) producing capacity of Corynebacterium pyogenes were studied in monocultures and in co-cultures with 1 or more of the organisms frequently accompanying it in summer mastitis in cattle (Peptococcus indolicus, Stuart-Schwan cocci, Bacteroides melaninogenicus subsp. levii, Fusobacterium necrophorum and Streptococcus dysgalactiae) or with organisms seldom associated with summer mastitis (Streptococcus uberis, Streptococcus agalactiae, non-toxic staphylococci and Escherichia coli).Pc. indolicus, and to some extent also Stuart-Schwan cocci, stimulated the growth as well as the hemolysin producing capacity of Gb. pyogenes (Table 1) while Str. dysgalactiae, Str. uberis, Str. agalactiae, E. coli and the majority of the staphylococci reduced these activities. Most F. necrophorum strains stimulated the growth, but not the hemolytic activity. With B. melaninogenicus the results were inconclusive.The effect of Pc. indolicus appeared to be associated with the production of a filterable factor (Tables 2 and 3).Mouse toxicity and hemolytic activity of culture filtrates were closely correlated (Table 4).  相似文献   

Sequence and expression analyses of the UL37 and UL38 genes of Aujeszky's disease virus     

Braun A  Kaliman A  Boldogköi Z  Aszódi A  Fodor I 《Acta veterinaria Hungarica》2000,48(1):125-136

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荷斯坦育肥牛饮喂甲醛液的增重效果试验     

李太平 《中国牛业科学》1997,(2)

选用西宁市奶牛场荷斯坦育肥牛 1 6头 ,随机分为试验组和对照组 ,每组为 8头。试验组饮喂 1 50 ppm甲醛液 ,对照组饮自来水。试验期 50天。结果表明 ,试验组和对照组平均增重分别为 51 .0 0千克和 2 8.50千克 ,日增重分别为 1 0 2 0克和 570克 ,差异极显著 (p<0 .0 1 )。  相似文献   

Antibacterial activity of seed proteins of Robinia pseudoacacia   总被引：1，自引：0，他引：1  

Talas-Oğraş T  Ipekçi Z  Bajroviç K  Gözükirmizi N 《Fitoterapia》2005,76(1):67-72

A low molecular weight cationic peptide was isolated from Robinia pseudoacacia seed and tested in vitro against seven bacteria (Corynebacterium michiganense, Staphylococcus aureus, Bacillus subtilis, Erwinia carotovora subsp. carotovora, Pseudomonas syringae pv syringae, Xanthomonas campestris pv campestris, and Escherichia coli). The peptide inhibited the growth of the tested strains. The effective concentrations required for 50% inhibition of bacterial growth ranged between 20 and 120 microg ml(-1) protein. S. aureus was found to be the most sensitive strain, however, E. coli was not affected much when compared with others. Reduction of antibacterial activity of the peptide with CaCl2 addition into the growth medium was also observed.  相似文献   

Fruit load and canopy shading affect leaf characteristics and net gas exchange of 'Spring' navel orange trees     

Syvertsen JP  Goñi C  Otero A 《Tree physiology》2003,23(13):899-906

Five-year-old 'Spring' navel (Citrus sinensis (L.) Osbeck) orange trees were completely defruited, 50% defruited or left fully laden to study effects of fruit load on concentrations of nitrogen (N) and carbohydrate, net assimilation of CO2 (Ac) and stomatal conductance (gs) of mature leaves on clear winter days just before fruit harvest. Leaves on defruited trees were larger, had higher starch concentrations and greater leaf dry mass per area (LDMa) than leaves on fruited trees. Both Ac and gs were more than 40% lower in sunlit leaves on defruited trees than in sunlit leaves on trees with fruit. Leaves immediately adjacent to fruit were smaller, had lower leaf nitrogen and carbohydrate concentrations, lower LDMa and lower Ac than leaves on non-fruiting branches of the same trees. Removing half the crop increased individual fruit mass, but reduced fruit color development. Half the trees were shaded with 50% shade cloth for 4 months before harvest to determine the effects of lower leaf temperature (Tl) and leaf-to-air vapor pressure difference on leaf responses. On relatively warm days when sunlit Tl > 25 degrees C, shade increased Ac and gs, but had no effect on the ratio of internal to ambient CO2 (Ci/Ca) concentration in leaves, implying that high mesophyll temperatures in sunlit leaves were more important than gs in limiting Ac. Sunlit leaves were more photoinhibited than shaded leaves on cooler days when Tl < 25 degrees C. Shade decreased total soluble sugar concentrations in leaves, but had no effect on leaf starch concentrations. Shading had no effects on canopy volume, yield or fruit size, but shaded fruit developed better external color than sun-exposed fruit. Overall, the presence of a normal fruit crop resulted in lower foliar carbohydrate concentrations and higher Ac compared with defruited trees, except on warm days when Ac was reduced by high leaf temperatures.  相似文献   

Rundschau     

RD i. R. Dr. Edmund Leib 《Journal of pest science》1986,59(4):77-78

Ohne ZusammenfassungPflanzenschutzorganisation für Europa und die Mittelmeerländer  相似文献   

Rundschau     

RD i. R. Dr. Emdund Leib 《Journal of pest science》1983,56(5):98-102

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Stand structure of an uneven-aged fir–beech forest with an irregular diameter structure: modeling the development of the Belevine forest, Croatia     

Juro Čavlović  Mario Božić  Andrej Boncina 《European Journal of Forest Research》2006,125(4):325-333

This study focuses on the problem of irregular diameter structure in a silver fir–beech selection (plenter) forest with a “surplus” of large diameter trees and a lack of natural regeneration and small diameter trees. We sampled 274 plots (900 m² each) in the Belevine research site (266.24 ha) in the mountain region Gorski Kotar (Croatia), where diameter (dbh) distribution, diameter increment, and natural regeneration were analyzed in detail. A low density of natural regeneration, weak annual recruitment of small (10 cm dbh) diameter trees (only five trees per hectare), delayed diameter growth of trees, and a low annual rate of trees reaching the next dbh class were attributed to the current irregular dbh structure. The stand development prediction for the next 50 years is based on a simulation model, which considers the current diameter structure, increment, recruitment, and future cutting regime. Intensive cutting in the first of five 10-year cutting cycles (intensity higher of 25%) is needed to initiate natural regeneration and to accelerate growth of young silver fir trees. In the next 50 years, the irregular diameter structure will be gradually improved.  相似文献   

Mutants in the lipopolysaccharide of Brucella ovis are attenuated and protect against B. ovis infection in mice     

Pedro Soler-Lloréns  Yolanda Gil-Ramírez  Ana Zabalza-Baranguá  Maite Iriarte  Raquel Conde-álvarez  Amaia Zú?iga-Ripa  Beatriz San Román  Michel S Zygmunt  Nieves Vizcaíno  Axel Cloeckaert  María-Jesús Grilló  Ignacio Moriyón  Ignacio López-Go?i 《Veterinary research》2014,45(1):72

Brucella spp. are Gram-negative bacteria that behave as facultative intracellular parasites of a variety of mammals. This genus includes smooth (S) and rough (R) species that carry S and R lipopolysaccharides (LPS), respectively. S-LPS is a virulence factor, and mutants affected in the S-LPS O-polysaccharide (R mutants), core oligosaccharide or both show attenuation. However, B. ovis is naturally R and is virulent in sheep. We studied the role of B. ovis LPS in virulence by mutating the orthologues of wadA, wadB and wadC, three genes known to encode LPS core glycosyltransferases in S brucellae. When mapped with antibodies to outer membrane proteins (Omps) and R-LPS, wadB and wadC mutants displayed defects in LPS structure and outer membrane topology but inactivation of wadA had little or no effect. Consistent with these observations, the wadB and wadC but not the wadA mutants were attenuated in mice. When tested as vaccines, the wadB and wadC mutants protected mice against B. ovis challenge. The results demonstrate that the LPS core is a structure essential for survival in vivo not only of S brucellae but also of a naturally R Brucella pathogenic species, and they confirm our previous hypothesis that the Brucella LPS core is a target for vaccine development. Since vaccine B. melitensis Rev 1 is S and thus interferes in serological testing for S brucellae, wadB mutant represents a candidate vaccine to be evaluated against B. ovis infection of sheep suitable for areas free of B. melitensis.  相似文献