The utility of microsatellite DNA markers for the evaluation of area-wide integrated pest management using SIT for the fruit fly, Bactrocera dorsalis (Hendel), control programs in Thailand

The oriental fruit fly, Bactrocera dorsalis (Hendel), is a key pest that causes reduction of the crop yield within the international fruit market. Fruit flies have been suppressed by two Area-Wide Integrated Pest Management programs in Thailand using Sterile Insect Technique (AW-IPM-SIT) since the late 1980s and the early 2000s. The projects’ planning and evaluation usually rely on information from pest status, distribution, and fruit infestation. However, the collected data sometimes does not provide enough detail to answer management queries and public concerns, such as the long term sterilization efficacy of the released fruit fly, skepticism about insect migration or gene flow across the buffer zone, and the re-colonisation possibility of the fruit fly population within the core area. Established microsatellite DNA markers were used to generate population genetic data for the analysis of the fruit fly sampling from several control areas, and non-target areas, as well as the mass-rearing facility. The results suggested limited gene flow (m < 0.100) across the buffer zones between the flies in the control areas and flies captured outside. In addition, no genetic admixture was revealed from the mass-reared colony flies from the flies within the control area, which supports the effectiveness of SIT. The control pests were suppressed to low density and showed weak bottleneck footprints although they still acquired a high degree of genetic variation. Potential pest resurgence from fragmented micro-habitats in mixed fruit orchards rather than pest incursion across the buffer zone has been proposed. Therefore, a suitable pest control effort, such as the SIT program, should concentrate on the hidden refuges within the target area.     

Inter-regional mating compatibility among Bactrocera dorsalis populations in Thailand (Diptera,Tephritidae)

Mating compatibility among recently colonized (wildish) populations of Bactrocera dorsalis (Hendel) from different geographic origins in Thailand was assessed through inter-regional mating tests. Outdoor octagonal nylon screen field cages containing single potted mango trees (Mangifera indica L.) were used. Sexual compatibility was determined using the index of sexual isolation (ISI), the male relative performance index (MRPI), and the female relative performance index (FRPI). The ISI values indicated that the northern population of Bactrocera dorsalis from Chiang Mai province was sexually compatible with the southern population of Bactrocera dorsalis (previously Bactrocera papayae) from Nakhon Si Thammarat province. The MRPI values showed that the northern males had a slightly higher tendency to mate than southern males, while the FRPI data reflected that females of both origins participated equally in matings. In all combinations there were no differences between homotypic and heterotypic couples in mating latency. Southern males tended to mate first with southern females, followed by northern males mating with northern females, while the latest matings involved heterotypic couples, in particular northern males mating with southern females. Overall, more couples were collected from higher parts of the field cage and the upper tree canopy, while there were no differences between the origins of flies in terms of elevation of couples within the cage. Laboratory assessments of fecundity showed no differences in the average number of eggs resulting from inter-regional crosses. Development of immature stages was also equal in the two hybrid crosses, with no differences found in the number of pupae produced, percentage pupal recovery, and percent adult emergence. The practical implication of this study is that colony of Bactrocera dorsalis derived from any northern or southern region of Thailand can potentially be used in sterile insect technique programs against this pest.     

Increased NO bioavailability in aging male rats by genistein and exercise training: using 4, 5-diaminofluorescein diacetate

Background

Some studies have suggested that the suppression of endogenous LH secretion does not seem to affect the majority of patients who are undergoing assisted reproduction and stimulation with recombinant FSH (r-FSH). Other studies have indicated that a group of normogonadotrophic women down-regulated and stimulated with pure FSH preparations may experience low LH concentrations that compromise the IVF parameters. The present study aimed to compare the efficacy of recombinant LH (r-LH) supplementation for controlled ovarian stimulation in r-FSH and GnRH-agonist (GnRH-a) protocol in ICSI cycles.

Methods

A total of 244 patients without ovulatory dysfunction, aged <40 years and at the first ICSI cycle were divided into two groups matched by age according to an ovarian stimulation scheme: Group I (n = 122): Down-regulation with GnRH-a + r-FSH and Group II (n = 122): Down-regulation with GnRH-a + r-FSH and r-LH (beginning simultaneously).

Result(s)

The number of oocytes collected, the number of oocytes in metaphase II and fertilization rate were significantly lower in the Group I than in Group II (P = 0.036, P = 0.0014 and P = 0.017, respectively). In addition, the mean number of embryos produced per cycle and the mean number of frozen embryos per cycle were statistically lower (P = 0.0092 and P = 0.0008, respectively) in Group I than in Group II. Finally the cumulative implantation rate (fresh+thaw ed embryos) was significantly lower (P = 0.04) in Group I than in Group II. The other clinical and laboratory results analyzed did not show difference between groups.

Conclusion

These data support r-LH supplementation in ovarian stimulation protocols with r-FSH and GnRH-a for assisted reproduction treatment.     

Increased NO bioavailability in aging male rats by genistein and exercise training: using 4, 5-diaminofluorescein diacetate

Background  

Several kinds of anti-oxidants have drawn a lot of intension for their benefits on vascular protection. In addition, it has been demonstrated that exercise training could improve endothelial function by up-regulating endothelial nitric oxide synthase (eNOS) protein. Therefore, the present study aims to investigate the effects of genistein, a potent phyto-antioxidant, and exercise training on age-induced endothelial dysfunction in relation to NO bioavailability using in situ NO-sensitive fluorescent dye detection.