Flight responses of Sitotroga cerealella (Lepidoptera: Gelechiidae) to corn kernel volatiles in a wind tunnel

The flight behavioral responses of males and females of Sitotroga cerealella (Lepidoptera: Gelechiidae) to corn kernel volatiles, in a wind tunnel, and the determination and identification of the active compounds of corn kernel volatiles were investigated. A wind tunnel bioassay was carried out to test the response of males and females to 15, 30, 60, and 120 g equivalents of corn kernel volatiles. Gas chromatography-electroantennography was used to determine which components in corn kernel volatiles elicited an EAD response using male and female antennae. Gas chromatography-mass spectrometry technique was used to identify the active compounds of corn kernel volatiles. A 60-g equivalent of corn kernel volatiles elicited attractant behavior of unmated males to landing near the source. Mated males and virgin females were not attracted to corn kernel volatiles. The number of mated females landing was significantly higher in 60- and 120-g equivalents of corn kernel volatiles, compared to the other concentrations and the control. The antennae of males and females responded to four active compounds of corn kernel volatiles. Three of these compounds were identified, namely nonanal, decanal, and geranyl acetone. It is suggested that host finding and selection by S. cerealella is associated with its host volatiles.     

Apolipoprotein C3 SstI polymorphism and triglyceride levels in Asian Indians

Background  

A close association between Sst I polymorphism in the 3' untranslated region of the apolipoproteinC3 (APOC3 ) gene and levels of plasma triglycerides (TG) had been reported by different investigators. Hypertriglyceridemia(HTG) is a known risk factor for coronary artery disease (CAD) in the context of Asian Indians. We conducted a study on the relationship between APOC3 SstI polymorphism (S1S1, S1S2 and S2S2 genotypes) and plasma TG levels in a group of 139 male healthy volunteers from Northern India.     

Interaction between organophosphate insecticides and the parasitic mite Acarophenax lacunatus (Prostigmata: Acarophenacidae) on Rhyzopertha dominica (Coleoptera: Bostrichidae)

The interaction between the organophosphate insecticides fenitrothion and pirimiphos-methyl with Acarophenax lacunatus (Cross & Krantz) (Prostigmata: Acarophenacidae), an egg parasite of the stored grain pest Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae), was assessed in a range of doses for each compound. The number of physogastric females of A. lacunatus and egg parasitism (%) decreased with increasing insecticide doses and mite density for both organophosphates. Lower insecticide doses for fenitrothion and pirimiphos-methyl and lower mite densities led to higher instantaneous rates of increase of the mite population. Overall lower instantaneous rates of increase of A. lacunatus were obtained with the insecticide pirimiphos-methyl. The sustained presence of the mite species in all insecticide doses suggest that this biological control agent may be used together with insecticide applications for controlling R. dominica, but high insecticide doses, mainly of pirimiphos-methyl, compromise mite population growth. The high rates of egg parasitism obtained with the biological control agent may aid the insecticide effect on the adult pest population preventing its outbreaks in wheat grains, constituting a potential tactic for pest management of stored wheat.     

混合线性模型下猪群间遗传联系的度量

采用关联指数(IC)和决定系数(CD)两种方法,度量混合线性模型遗传评估下 猪群体间的遗传关联性。结果表明,加拿大安大略省的大约克夏猪、长白猪、杜洛克猪和汉普夏猪4个主要品种群体间具有良好的遗传联系。CD法既组合了数据结构和信息量,又考虑了预测误差方差和遗传变异性,是一个选择判断遗传评估精度的好方法。 Abstract:Two criteria for the measures of genetic connectedness in mixed linear model of genetic evaluation are used:the degree of connectedness(IC)and the generalized coefficient of determination(CD).The results indicated that the data of four dominant swine breeds:Yorkshire,Landrace,Duroc and Hampshire in Ontario,Canada are well connected.The CD,which combines data structure and amount of information and also accounts for both prediction error variance and genetic variability,is a good method to select for judging the precision of a genetic evaluation.     

Motile sperm organelle morphology examination (MSOME): intervariation study of normal sperm and sperm with large nuclear vacuoles

Background  

Although the motile sperm organelle morphology examination (MSOME) was developed only as a selection criterion, its application as a method for classifying sperm morphology may represent an improvement in evaluation of semen quality, with potential clinical repercussions. The present study aimed to evaluate individual variations in the motile sperm organelle morphology examination (MSOME) analysis after a time interval.     

Biological efficacy and persistence of biphenthrin sprayed on maize at different grain temperatures

The objective of this work was to evaluate the immediate and latent effects of the grain temperature, during the spraying process, on the persistence and biological efficacy of the biphenthrin insecticide against Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) and Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). For such, biphenthrin was sprayed on the grain at the temperatures: 25, 30, 35, 40 and 45 degrees C. To access the persistence of biphenthrin, insecticide residue analyses were carried out monthly, just after spraying until 90 days of storage. To evaluate the biological efficacy of biphenthrin, 20 adults of each species were placed in petri dishes with sprayed grain, and kept in climate cabinets under 27 degrees C and 55% of RH, during 48h. Evaluations were done every 15 days, starting just after spraying and finishing at 90 days of storage. Both persistence and biological efficacy of biphenthrin reduced as storage time and grain temperatures increased. Additionally, S. zeamais was more tolerant to biphenthrin than T. castaneum.     

The many roles of small RNAs in leaf development

Leaf development involves many complex genetic interactions,signals between adjacent cells or between more distant tissues and consequent changes in cell fate.This review describes three stages in leaf development where regulation by small RNAs have been used to modulate gene expression patterns.     

Susceptibility of Acarophenax lacunatus (Cross & Krantz) (Prostigmata: Acarophenacidae) to Sulfur

The parasitic mite Acarophenax lacunatus (Cross & Krantz) is a potentially important biocontrol agent of stored grain insect pests, but its presence in insect mass rearing is undesirable. This study was carried out to evaluate the susceptibility of A. lacunatus to sulfur. The experimental units were petri dishes containing 30 g of whole wheat grains infested with 30 adults of Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae). The treatments consisted of pulverizing the wheat grains with sulfur, at 0, 0.15, 0.3, 0.6, 0.9 and 1.2 mg a.i./g, in five replicates. Three inoculations of A. lacunatus were carried out in each petri dish at five, ten and fifteen days after infestation with R. dominica. The petri dishes were stored for 60 days at 30 +/- 1 degree Celsius, 60 +/- 5% R.H. and 24h scotophase. The parasitic mite was susceptible to all sulfur doses used in the test. The number of eggs of R. dominica parasitized by A. lacunatus showed a decreasing trend with the increase in doses of sulfur, as did the number of physogastric females of the mite. The mite showed a negative correlation of their instantaneous rate of increase with sulfur dose. No mites developed at sulfur doses higher than 0.3 mg a.i./g. The susceptibility of A. lacunatus to sulfur is an important aspect to consider in the control of this parasitic mite in colonies of R. dominica. In addition, this control method has low cost and is easy to use.