• Korean journal of applied entomology
• /
• v.7
• /
• pp.15-20
• /
• 1969

This experiment was planned to study the mating behavior of the fall webworm. Hyphantria cunea Drury. In this experiment. observations on mating behavior of the fall webworm were based on the time of moth emergence, time of mating activity, copulation period, mating frequency, and effect of moth ages on the mating ratio. Mating frequency was determined by visual observation and the number of spermatophores. The results obtained were as follows; 1) The moths started emerging at about 3 P. M. and ended at about 12 P. M. The peak of moth emergence was between 7 and 8 P. M. Total ratio or the moths emerged between 7 and 8 P. M. was 42. 1 for female and 41.8 for male. 2) Mating activity was mostly confined to the period between 5 and 6 A. M. The average complation period was 12 hours (ranges between 7 and 17 hours). 3) The average ratio of single mating was $66.0\%$ for both sexes, and that of double. matings were $4.1\%$ for females and $5.4\%$ for males in laboratory test. The mating ratio of female moths collected from the field was $62.1\%$ for single mating. and 15.5" for doubles matings. These data indicated that single mating seemed to be most common. 4) Mating usually occured within four days after the emergence from the pupae. Mating ratio was greatly varied with the moth ages. The highest mating ratio was observed within 6 to 15 hours after moth emergence. Both sexes usually mated with the moths of the same ages.

• Journal of Life Science
• /
• v.12 no.2
• /
• pp.173-181
• /
• 2002

This study was conducted to do the comparative analysis of mating type locus controlling the direct formation of fruiting body in Schizophyllum commune which is indigenous to North America with that of other identified mating locus. The 3120 bp Y-region nucleotide of A $\alpha$ 3 mating locus activating a developmental pathway in S. commune was determined, and appeared to have about 96% homology to S. commune 1-71 $A\alpha$3 allele indigenous to South America, showing strongly a conservative feature. This nucleotide analysis also showed above 96% homology highly in the seven presumed exons, and about 97% in the acidic rich region (AR), about 99% in homeodomain (H7), about 97% in the basic rich region (BR), about 95% in the serine rich region (Ser) respectively. In the comparative analysis to the translated polypeptide sequence, S. commune A $\alpha$ 3 mating locus containing Y-region also showed about 97% homology to the region of S. commune indigenous to North America, but the identity ratio to Y1 including Y4, Y5, Y6 different allele types was declined to about 41~49%. In the analysis of functional loci controlling mating activity, it is assumed to have a highly conservative feature showing about 98% homology in homeodomain polypeptide. Especially, it is notable that the homology ratio of above 85% in homeodomain motif between mating type alleles was higher than in the AR, BR, Ser showing about 10~50% homology.

• The Korean Journal of Mycology
• /
• v.49 no.4
• /
• pp.487-495
• /
• 2021

Lentinula edodes is a tetrapolar basidiomycete and its mating type is determined by two unlinked genetic loci, A and B. Theoretically, one dikaryotic strain could produce basidiospores with four different mating types in a 1:1:1:1 ratio. Previous studies have described the skewed segregation ratio of mating types among basidiospores of L. edodes. However, they were based only on morphological characteristics, such as clamp connection, to determine mating types. To clarify whether the segregation distortion of mating types is a general phenomenon in L. edodes, we analyzed the mating types of basidiospores obtained from three cultivars of L. edodes using recently developed DNA markers. We found that the skewed segregation of mating types was strain-specific, as reported previously. Among the three cultivars, one cultivar showed balanced segregation, while the other two displayed distorted segregation. We also examined the relationship between mating type and mycelial growth rate of monokaryons derived from each basidiospore. It was found that the monokaryotic mycelial growth rate was related to the A mating type but not to the B mating type. Therefore, homeodomain transcription factor genes that reside on the A locus or other genes linked to the A locus affect the growth rate of monokaryotic mycelia. Considering the importance of mating types in mushroom breeding, this study is informative for establishing an efficient breeding strategy as well as for understanding the mechanism of monokaryotic mycelial growth.

• Korean Journal of Animal Reproduction
• /
• v.16 no.3
• /
• pp.261-267
• /
• 1992

The reproductive performance of SPF ICR mice under single paired mating were examined to get reproductive background data and to establish single paired rotational mating system. The results obtained were as follows : average litter size was 15.4$\pm$2.0 heads ; average weaning rate was 95.7$\pm$4.9% ; sex ratio(male/female) was 1.09$\pm$0.26 ; aveage delivery interval was 23.0$\pm$2.4 days. It was given the largest litter size at the age of 121~150 days and in 2nd~4th parities, but at the age of under 90 days and in 1st parity weaning rate and delivery interval were higher and shorter than those of the other ages and parities, respectively. In sex ratio, the number of male litters was slightly increased from that of female litters. The weaning rate of litters from dams which nuresed 12 litters was the highest among those of different litter sizes, and it was decreased dependent upon increment of litter size. There were no difference among 4 groups for reproductive performance, therefore the present study could have important sources for animal breeders who produce mice using the single paired rotational mating system.

• Korean Journal of Animal Reproduction
• /
• v.10 no.2
• /
• pp.182-187
• /
• 1986

As a fundamental study to increase the fertility and to modify the sex ratio in cattle, highly motile sperm were separated by bovine serum albumin gradients. The pregnancy rates of Korean native cow and Holstein cow, and the sex ratio between AI and natural mating were also investigated. The results obtained were as follows. 1. First service pregnancy rate of Korean native cow in artificial insemination was higher than that of Holstein. 2. At secondary sex ratio in artificial insemination and natural mating, male ratio in artifical insemination was slightly higher than that in natural mating. 3. The sperm separated from marketed frozen semen using 6%, 10% and 20% bovine serum albumin showed significantly high value in motility, percent of normal sperm and progressive motility as compared with control sperm.

• The Plant Pathology Journal
• /
• v.38 no.2
• /
• pp.78-89
• /
• 2022

Phaeosphaeria species are pathogenic on wheat, barley and a wide range of wild grasses. To analyze mating type loci of the Phaeosphaeria species and investigate mating type distribution in Iran, we sequenced mating type loci of 273 Phaeosphaeria isolates including 67 isolates obtained from symptomatic leaves and ears of wheat, barley, and wild grasses from two wheat growing region in Iran as well as 206 isolates from our collection from other regions in Iran which were isolated in our previous studies. Mating type genes phylogeny was successfully used to determine the species identity and relationships among isolates within the Phaeosphaeria spp. complex. In this study, we reported seven new host records for Phaeosphaeria species and the Phaeosphaeria avenaria f. sp. tritici 3 group was first reported from Iran in this study. Mating type distribution among Phaeosphaeria species was determined. Both mating types were present in all sampling regions from Iran. We observed skewed distribution of mating types in one region (Kohgiluyeh va Boyer-Ahmad) and equal distribution in the other region (Bushehr). However, when considering our entire dataset of 273 Iranian Phaeosphaeria isolates, the ratio of mating types was not deviated significantly from 1:1 suggesting possibilities for isolates of opposite mating type to interact and reproduce sexually, although the sexual cycle may infrequently occur in some regions especially when the climatic conditions are unfavorable for teleomorph development.

• Journal of Ecology and Environment
• /
• v.31 no.1
• /
• pp.17-21
• /
• 2008

Mating behaviour of the gammarid amphipod, Hyale rubra, was observed. H. rubra displayed precopulatory mate guarding: males clasped females with their gnathopods during copulation, forming a pair. Males also participated in embryo care during the incubation period. The population was small, and the sex ratio was almost equal. Energy allocation for mating effort and parental effort in the two sexes appear to be almost equal. The mating system was sequentially polygamous (or promiscuous) and there was conspicuous sexual dimorphism in the size of the gnathopod, which was used for mate guarding. However, there appears to be relatively weak sexual competition for mating opportunities despite conspicuous sexual dimorphism. H. rubra did not display territorial competition or external fertilization. Nevertheless, the male provided paternal care. Since H. rubra inhabit tide pools and live on algae, the polygamous mating system of the species can be explained by the polygyny threshold model. The evolution of mate guarding and parental care may have been favored by the species' low population density and harsh environments, an interpretation consistent with the optimality model.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.9 no.4
• /
• pp.59-65
• /
• 2010

This paper presents the study on the contact stress analysis of a pair of mating spur gears during rotation. Contact stress analysis is performed between two spur gear teeth at different contact positions during rotation. An example is presented to investigate the variation of contact stress on a pair of mating gears with contact positions. The variation of contact stress during rotation is compared with the contact stress at lowest point of single tooth contact(LPSTC) and AGMA Equation for contact stress. The results show that contact stress varies along the contact position and gets maximum values in the beginning and end of the contact. In this study, the gear design considering the contact stress on a pair of mating gears is more severe than that of AGMA standard.

• Journal of Aquaculture
• /
• v.22 no.1
• /
• pp.16-22
• /
• 2009

Life history of Korean crayfishes Cambaroides similis (Koelbel) was studied 8 month from March to October, 2006 from the Gwanak mountain, Seoul, South Korea. By capture and recapture method, 551 crayfishes were collected analyzed during the experimental period. Based on the distribution pattern of body lengths, the local population putatively divided into four age groups. The sex ratio of male and female was almost equal. However, their growth rates varied by water temperature. Early juveniles seen during June became adult during August. The study findings suggest that late autumn is mating season.

• Korean journal of applied entomology
• /
• v.30 no.2
• /
• pp.101-105
• /
• 1991

The host finding, ovipostition of Anagrus incarnafus Haliday and the sex ratio of its offsprings was determined. Both male and female mate immediately after emergence and the female parasitoid search for host eggs by drumming with antenna immediately after release on the rice seedings. Time required for the host searching, drumming with antenna, tapping and inserting with ovipositor, and ovipositing of A. incarnaws takes 188.5, 17.5, 72.4 and 206.7 seconds, respectively. The time required for mating takes 16-21 seconds. The sex ratio of offsprings between female and male was about 3: 1 in mated females and all the offsprings emerged from the eggs of unmated females were males. So, A. incarnafus can reproduce zygogenetically and parthenogenetically and the mode of parthenogenetic reproduction was an arrhenotokous parasitoid.