Mapping of QTLs conferring resistance in rice to brown planthopper, Nilaparvata lugens

Brown planthopper (BPH), Nilaparvata lugens Stål (Hemiptera: Delphacide), is a destructive insect pest of rice, Oryza sativa L. (Poaceae), in rice-producing areas worldwide. Host plant resistance is a major aspect of managing this pest. In this study, a mapping population consisting of 150 F3 lines, derived from a cross of MR276 and Rathu Heenati, was used to detect and analyse quantitative trait loci (QTLs) for the resistance to BPH. Composite Interval Mapping (CIM) was used for QTL detection. In total 10 QTLs controlling BPH resistance were mapped on chromosomes 1, 3, 6, 7, 9, 10, and 12. Four QTLs – qBph-1-1, qBph-3-1, qBph-6-1, and qBph-7-1 – were mapped on chromosomes 1, 3, 6, and 7 in the standard seedbox screening test, explaining 41% of the phenotypic variance. Two QTLs, qBph-6-1 and qBph-9-1, were detected on chromosomes 6 and 9 in the honeydew test, accounting for 32% of the total phenotypic variance. Moreover, four QTLs – qBph-3-1, qBph-6-1, qBph-10-1, and qBph-12-1 – were identified on chromosomes 3, 6, 10, and 12 expressing antixenosis to BPH and explaining 41% of the phenotypic variance. QTL qBph-3-1 was located in the chromosomal region between markers RM231 and RM3872 on chromosome 3, and QTL qBph-6-1 was located in the region between RM588 and RM204 on chromosome 6, indicating that these regions have a major effect in controlling the resistance to BPH in the population studied. The molecular markers linked to QTLs that are identified will be useful in the development of varieties resistant to BPH. Our study contributes to the development of genetic material for breeding programmes and marker-assisted selection (MAS) in rice to improve BPH resistance

Path analysis of the relationship between optimism, humor, affectivity, and marital satisfaction among infertile couples

Marital satisfaction is an important factor for establishing a family relationship, feeling satisfied, and living happily together. The aim of the present study was to investigate the relationship between optimism, humor, positive and negative affect, and marital satisfaction among infertile couples. The sample comprised 80 infertile Iranian couples (n = 160) who visited infertility clinics. Participants completed a series of Persian versions of psychometric scales related to optimism (Attributional Style Questionnaire), humor (Humor Styles Questionnaire), marital satisfaction (Enrich Marital Satisfaction Questionnaire), positive affect (PA) and negative affect (NA) (Positive and Negative Affect Schedule). The obtained result of Smart PLS statistical analysis confirmed the significant positive correlation between optimism and humor with marital satisfaction and high PA and low NA. Moreover, the findings also provided an adequate fit of the model. The findings demonstrated that infertile couples high in optimism and humor have higher levels of marital satisfaction and high PA and low PA. Based on the study’s findings, interventions for facilitating optimism and humor among infertile couples are discussed

A survey on some risk factors and evaluation of their impacts on streptococcosis incidence in rainbow trout farms in west of Mazandaran province

This study aimed to investigate the effects of 5- parameter dissolved oxygen, PH, nitrite, nitrate and temperature of the water on Streptococcosis incidence in two groups of fry and grower fish. Research was performed at west Mazandaran province -Tonkabon region in 12 rainbow trout selected farms. Research conducted in 3 farms with well source water, 8 farms with water source of the river of Dohezar and one farm with water source of the river of Azarood, during 12 consecutive months. From 1390.04.01 to 1391.04.01, once time each month, and in each time 10 fish randomly sampled, inlet water were sampled simultaneously Of 1350 sampled fish 607 fish with an average weight 22.04 gr, average length 12.59 cm were in fry category and 743 fish with an average weight 156.25 gr, average length 23.32 cm in were grower category. Streptococcosis observed only in grower category Of 72 fish with clinical signs of the disease, 14 numbers were positive Streptococcosis (19.44%) and 58 numbers were negative Streptococcosis (80.55%). Three fish from grower category has not any clinical signs of disease and seemed to be healthy but were positive Streptococcosis in examinations (0.22% of total fish sampled. Fish with clinical signs of the disease but negative Streptococcosis were of at least 55.1 gr and at most weight 417 gr respectively. The results showed that 47.07% cases of Streptococcosis happened at 15.6°C water temperature, 35.29% at 16.98°C and 17.64% cases happened at 18.04°C so that 100% of Streptococcosis cases was observed at the average temperature of 16.99°C. In addition, the survey results show that despite relatively high levels of nitrite in source water of farms from wells, nitrite does not effect on the disease incidence. It seems that an optimal level of dissolved oxygen in water is effective in reducing the effectiveness of nitrite in this disease. According to equation coefficients logit model is as follows: According to Logit model, it seems that for every degree change in temperature and pH of water, morbidity change will diminish 0.37 % and 1.74 % respectively. 80.56% of fish sampled that had the clinical symptoms, was ranging from an average weight of 5.1 gr (fry) and 417 gr (grower fish), that despite having clinical signs of the disease were negative Streptococcosis. Isolation of Staphylococcus bacteria as well as Gram-negative bacilli from fish with clinical symptoms similar to the symptoms of Streptococcosis, may indicate the involvement of other pathogens in fish clinical signs

PERFORMANCE OF YIELD AND YIELD CONTRIBUTING CHARACTERISTICS OF BC2F3 POPULATION WITH ADDITION OF BLAST RESISTANT GENE

ABSTRACTThe study was carried out in the University Putra Malaysia (UPM) Rice Research Centre to evaluate the yield performance of newly developed selected blast resistant plants of BC2F3 generations derived from a cross between MR263, a high yielding rice variety but blast susceptible and Pongsu Seribu 1, donor with blast resistant (Pi-7(t)and Pi-d (t)1, Pir2-3(t)genes and qLN2 QTL), Malaysian local variety. On the basis of assessed traits, the plants 12, 6, 7, 5, 21, 22, 5, 26, 11, 8, 10, 13 and 15 had the higher yield, blast resistant and good morphological traits. More than 70% heritability was found in days to maturity, plant height, tiller numbers per hill, and panicle per hill, 80% heritability was found in filled grain and yield per hill and more than 90% heritability was found in grain length, grain width and seed weight. Cluster analysis based on the traits grouped 30 plants along with MR263 into seven clusters. According to PCA, the first four principal components account for about 69.3% total variation for all measured traits and exhibited high correlation among the characteristics analyzed

Hybrid Hydrogel Based On Pre-Gelatinized Starch Modified With Glycidyl-Crosslinked Microgel

Hybrid hydrogels based on pre-gelatinized starch were synthesized by inverse emulsion polymerization through modifying the starch with a glycidyl-crosslinked microgel. Glycidyl-crosslinked microgel is a special latex with high ability to impart hydrophilic characteristics to various substrates. Glycidyl-crosslinked microgel latexes with various structures were synthesized, and the effect of latex type on swelling capacity of the hybrid hydrogels based on pre-gelatinized starch was investigated. The highest swelling capacity was achieved for a pre-gelatinized starch modified with a glycidyl-crosslinked microgel latex based on poly(acrylic acid, sodium acrylate, acrylamide, 2-acrylamide-2 methyl propane sulfonic acid) (AA–SA–AM–AMPS). The swelling values of this hybrid hydrogel in distilled water and saline solution were 52.4 and 28.8 g/g, respectively. A key advantage of these hybrid hydrogels is that starch constitutes 64% of their structure. Given the fact that such hybrid hydrogels display low absorbency under load (AUL), they were surface crosslinked using microwave heating instead of conventional heating. Ethylene glycol diglycidyl ether was used as surface crosslinker. The AUL of the surface crosslinked hybrid hydrogels was increased by 85%. The hydrogels were characterized using FTIR, thermogravimetric analysis, scanning electron microscopy, and rheological measurements