Variation in tree growth characteristics, stress-wave velocity, and Pilodyn penetration of 24-year-old teak (Tectona grandis) trees originating in 21 seed provenances planted in Indonesia

Growth characteristics [stem diameter (D), tree height (H), and bole volume (V)], stress-wave velocity (SWV), and Pilodyn penetration (P) were measured for 21 seed provenances of 24-year-old teak trees planted in Indonesia to characterize variation in tree growth characteristics, SWV, and P among seed provenances. Broad-sense heritability and correlations between the measured characteristics were also determined. Significant differences for all measured characteristics were observed among provenances, indicating that these characteristics are genetically controlled. Broad-sense heritabilities of growth characteristics, SWV, and P are moderate values. These results indicate potential for improving growth characteristics and wood properties of teak trees with the help of breeding programs. Highly significant positive correlations were observed among the growth characteristics, suggesting that they are closely related. In contrast, no significant correlations were observed between the growth characteristics and SWV, indicating that they are independent. We conclude that mechanical properties are also important criteria for selecting plus trees in tree breeding programs. Principal component analysis revealed that seed provenances from Indonesia (Bangilan, Deling, and Randublatung) and India (Malabar and Central Province) have high scores of growth characteristics and SWV.     

Correction to: Chlorantraniliprole application differentially affects adult emergence of Sympetrum dragonflies in rice paddy fields

Paddy and Water Environment -     

Short-term responses of adult kuruma shrimp Marsupenaeus japonicus (Bate) to environmental salinity: osmotic regulation, oxygen consumption and ammonia excretion

The effects of salinity on haemolymph osmolality, oxygen consumption and ammonia excretion were investigated in adult kuruma shrimp, Marsupenaeus japonicus (Bate), at salinities of 20, 25, 30 and 35 g L^?1. Haemolymph osmolality showed a positive linear relationship (r²=0.9854) with medium osmolality. The isosmotic point calculated from this relationship was 1039 mOsm kg^?1, which corresponds to a salinity of approximately 35 g L^?1. The slope of the regression equation was very high (0.81), suggesting that M. japonicus adults are poor osmoregulators compared with the adults of other penaeids and to conspecific young. The difference between haemolymph and medium osmolality (D_OP) was lowest at 35 g L^?1 and highest at 20 g L^?1. Thus, the minimum D_OP coincided with the isosmotic point of the shrimp. The respiration rate was significantly lower at 30 g L^?1 than at the other salinities. Ammonia excretion rates were inversely related with salinity and therefore were minimal at 35 g L^?1. The results of this study suggest that the optimum salinity for adult kuruma shrimp is around 30–35 g L^?1 and that even minor (e.g. 5 g L^?1) deviations from this optimum cause significant physiological changes. Further, the observed increases in oxygen consumption and ammonia excretion during exposure to low salinities, which indicate higher energy expenditure and amino acid catabolism for osmoregulation, respectively, suggest that the growth efficiency of M. japonicus adults may be severely compromised by hypohaline water inflow into the rearing ponds.     

Complete mitochondrial DNA sequence of Atlantic horse mackerel Trachurus trachurus and molecular identification of two commercially important species T. trachurus and T. japonicus using PCR-RFLP

ABSTRACT:   To characterize and identify mitochondrial DNA (mtDNA) nucleotide sequence variation in two commercially important Trachurus species, Trachurus trachurus and T. japonicus , the complete mtDNA sequence of T. trachurus was determined. The T. trachurus mtDNA consists of 16 559 bp, containing 22 transfer RNA (tRNA) genes, two rRNA genes, and 13 protein-coding genes. Comparing the mtDNA nucleotide sequences of the Trachurus species, a polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) method was developed to differentiate these two commercially important species. The primer pair Lt1-ND5 and Ht1-ND5, corresponding to ND5 , was designed to amplify a 360-bp fragment. Following digestion with Eco  RI, the PCR product for T. japonicus resulted in 93- and 267-bp fragments, while T. trachurus lacked a restriction site for Eco  RI. In contrast, after digestion with Hin  fI, the T. trachurus PCR product yielded 44-, 84-, and 232-bp fragments, while the T. japonicus product was not digested. The PCR-RFLP analysis established in the present study was useful for identifying T. trachurus and T. japonicus .     

Biocontrol of Pythium root rot on lisianthus using a new dark septate endophytic fungus Hyaloscypha variabilis J1PC1

European Journal of Plant Pathology - Pythium root rot is one of the most destructive diseases on lisianthus in Japan. Current management strategies against Pythium root rot are insufficient in...     

Glycosphingolipid receptors for pathogenic vibrios in intestines of mariculture fish

Vibrios are highly motile, facultatively anaerobic bacteria that are ubiquitous in aquatic environments and part of the normal intestinal microflora of healthy fish, but some species can cause vibriosis. The adherence of vibrios to host fish intestines is a significant event not only for their survival and growth, but also in terms of pathogenicity. However, the molecular mechanism underlying the adhesion of vibrios to the intestinal tract of fish is not fully understood. We report here the identification of intestinal glycosphingolipid (GSL) receptors to which pathogenic vibrios attach in typical mariculture fish. Thin-layer chromatography overlay assays using five species of ³⁵S-labeled vibrios and intestinal glycosphingolipids of seven species of mariculture fish revealed that all of the fish tested possessed GM3 (NeuAcα2-3Galβ1-4Glcβ1-1′Cer) and/or GM4 (NeuAcα2-3Galβ1-1′Cer) as major acidic intestinal GSLs and that all of the vibrios tested specifically adhered to GM3 and/or GM4. Our results demonstrate that these GSLs were able to function as a receptor for the various vibrios tested. Analysis of the relationship between sugar structure and receptor activity for vibrios revealed that ‘NeuAcα2-3Galβ1-’ is required at the non-reducing end of glycosphingolipids for the bacteria to attach.