Artificial Selections for Life‐History Traits Affect Effective Cumulative Temperature and Developmental Zero Point in Zeugoducus cucurbitae

큰이십팔점박이무당벌레(Henosepilachna vigintioctomaculata (Motschulsky))의 강릉지역 발생소장과 발육단계별 감자잎 섭식량 및 온도별(10, 15, 20, 25, <TEX>$30^{\circ}C$</TEX>) 발육소요기간을 조사하였다. 큰이십팔점박이무당벌레는 연 3회, 즉 5월 하순, 6월 하순 및 8월 하순에 발생하였으며, 특히 5월 하순부터 7월 중순까지 높은 밀도로 발생하여 감자 식물체를 집중적으로 가해하였다. 발육단계별 감자잎 섭식량은 유충의 영기가 진전될수록 많았으며, 4령 유충기에 가장 많은 섭식량을 보였다. 큰이십팔점박이무당벌레 부화율과 우화율은 각각 <TEX>$10^{\circ}C$</TEX> 및 <TEX>$30^{\circ}C$</TEX>에서는 매우 낮았고 <TEX>$20{\sim}23^{\circ}C$</TEX>에서 가장 높았다. 알에서 성충으로 우화되기까지 발육단계별 생육기간은 온도가 증가함에 따라 감소하였는데, <TEX>$10^{\circ}C$</TEX>에서 90일 정도로 매우 느렸으며 <TEX>$20^{\circ}C$</TEX>에서는 40여일, <TEX>$25^{\circ}C$</TEX>에서는 25일이 소요되었다. 또한 발육영점온도와 유효적산온도는 알에 대해서 <TEX>$7.3^{\circ}C$</TEX>와 83.3 DD, 유충에 대해서 <TEX>$5.2^{\circ}C$</TEX>와 294.1 DD, 번데기에 대해서 <TEX>$6.2^{\circ}C$</TEX>와 97.1 DD이었다. The seasonal fluctuation of the large 28-spotted lady beetle, Henosepilachna vigintioctomaculata (Motschulsky), was observed in potato fields of Gangneung region, Gangwondo Province. The effects of their leaf consumption over a 24 hour period and developmental periods by different temperatures were investigated, and then the developmental threshold (DT) and effective cumulative temperature (ET) of each stage were calculated. Various developmental stages of H. vigintioctomaculata were captured in the fields from May to September, with three peaks in late May, late June, and late August. Leaf consumption by larval stages increased with the development of instar. The 4th instar larvae consumed potato leaves much more than other stages. Egg hatchability and emergence rate of H. vigintioctomaculata were lower at <TEX>$10^{\circ}C$</TEX> and <TEX>$30^{\circ}C$</TEX>, but higher at around <TEX>$20{\sim}23^{\circ}C$</TEX>. The developmental periods of each stage became shorter as temperature increased; 90 days at <TEX>$10^{\circ}C$</TEX>, 40 days at <TEX>$20^{\circ}C$</TEX> and 25 days at <TEX>$25^{\circ}C$</TEX>. Base on developmental velocity to temperature, calculated DT and ET were <TEX>$7.3^{\circ}C$</TEX> and 83.

The effective cumulative soil temperature in relation to the potential germination of P. densiflora seed was investigated and the results are presented in this study. The laboratory experiment was carried out in the chamber at 5°C, 8°C, 10°C, 15°C, 20°C, 25°C, 30°C and 35°C under both light (3, 000 lx) and dark conditions. The daily germination rate was observed. Initial effective cumulative soil temperature was fixed at 5°C, because the seeds did not germinate at 5°C. From the laboratory experiment at 8°C, 10°C and 15°C, it became obvi ous that, from 75°C•day to 200°C•day (germination period) the P. densiflora seed germinates. Five-day periods of effective cumulative soil temperature, 75°C•day are estimated from the data of the geographical distribution of soil temperature, which is considered to be the beginning of the P. densiflora seed germination in various places. As a consequence, the following facts have been observed (Fig. 4(a)): The first five-day period line of May passes through the southern area of Hokkaido. The first five-day period line of April passes through the Kanto district, Nagano, Gifu, the southern area of Fukui, Tottori Prefectures and Oki Island. That line of March passes through Izu Peninsula, Shizuoka Prefecture, Kui Peninsula, Seto Inland Sea and the central area of Kyushu. The line of February passes through the southern edge of Shikoku and the southern area of Kyushu. Next, the five-day periods of the effective cumulative soil temperature of the ending of the P. densiflora seed germination, that is 200°C•day, are worked out and the results are as follows (Fig. 4(b)): The first five-day period line of June passes through the northeast of Hokkaido. That of May passes through Miyagi, the central area of Yamagata Prefectures and the mountainous area of Jyo-shinetsu. That line of April passes through the south of Honshu, Seto Inland Sea and the central area of Kyushu. The line of March passes through the southern edge of Kui Peninsula, Shikoku and Kyushu. Germination period of P. densiflora seed, that is the period from 75°C•day to 200°C•day, is shorter in northeast Japan compared with that of southwest Japan (Fig. 4(c)). Therefore, there are two deficits in northeast Japan, those are, first the germination time is later and the second the germination period is shorter than in southwest Japan.

The relationship between the meteorological elements, especially the thermal conditions and the Poaceae pollen appearance in the air, were analysed as a basis to construct a useful model predicting the grass season start. Poaceae pollen concentrations were monitored in 1991–2012 in Kraków using the volumetric method. Cumulative temperature and effective cumulative temperature significantly influenced the season start in this period. The strongest correlation was seen as the sum of mean daily temperature amplitudes from April 1 to April 14, with mean daily temperature >15 °C and effective cumulative temperature >3 °C during that period. The proposed model, based on multiple regression, explained 57 % of variation of the Poaceae season starts in 1991–2010. When cumulative mean daily temperature increased by 10 °C, the season start was accelerated by 1 day. The input of the interaction between these two independent variables into the factor regression model caused the increase in goodness of model fitting. In 2011 the season started 5 days earlier in comparison with the predicted value, while in 2012 the season start was observed 2 days later compared to the predicted day. Depending on the value of mean daily temperature from March 18th to the 31st and the sum of mean daily temperature amplitudes from April 1st to the 14th, the grass pollen seasons were divided into five groups referring to the time of season start occurrence, whereby the early and moderate season starts were the most frequent in the studied period and they were especially related to mean daily temperature in the second half of March.

Biological clocks regulate various behavioural and physiological traits; slower circadian clocks are expected to slow down the development, suggesting a potential genetic correlation between the developmental period and circadian rhythm. However, a correlation between natural genetic variations in the developmental period and circadian rhythm has only been found in Bactrocera cucurbitae. The number of genetic factors that contribute to this genetic correlation is largely unclear. In this study, to examine whether natural genetic variations in the developmental period and circadian rhythm are correlated in Drosophila melanogaster, we performed an artificial disruptive selection on the developmental periods using wild-type strains and evaluated the circadian rhythms of the selected lines. To investigate whether multiple genetic factors mediate the genetic correlation, we reanalyzed previously published genome-wide deficiency screening data based on DrosDel isogenic deficiency strains and evaluated the effect of 438 genomic deficiencies on the developmental periods. We then randomly selected 32 genomic deficiencies with significant effects on the developmental periods and tested their effects on circadian rhythms. As a result, we found a significant response to selection for longer developmental periods and their correlated effects on circadian rhythms of the selected lines. We also found that 18 genomic regions had significant effects on the developmental periods and circadian rhythms, indicating their potential for mediating the genetic correlation between the developmental period and circadian rhythm. The novel findings of our study might lead to a better understanding of how this correlation is regulated genetically in broader taxonomic groups.

Three strains of Aedes aegypti and 3 strains of Ae. albopictus of laboratory colonies were reared in different temperatures to compare their development in the immature stage (larval and pupal periods). The duration of developmental times of Ae. aegypti strains averaged 31.0-32.0 days at 15℃, 13.9-16.6 days at 20℃, 10.2-11.8 days at 25℃ and 7.4-8.2 days at 30℃. The developmental zero was 8.2-10.6℃ and the effective cumulative temperature was 145-176 days degree. For Ae. albopictus the duration of developmental times averaged 12.6-15.1 days at 20℃, 10.0-11.7 days at 25℃ and 7.6-8.4 days at 30℃. The developmental zero was 4.2-8.2℃ and the effective cumulative temperature was 166-214 days degree. Male adults emerged 0.2-1.0 days faster than females due to a difference in the duration of the 4th-instar larval period. Aedes aegypti that easily breeds in urban environment could be re-established if introduced in Japan.

An efficacious strategy to adapt to climate change involves optimizing the planting season, a technique that has been extensively utilized to enhance the use of solar radiation and temperature resources in rice cultivation. Field experiments were executed in the middle and lower reaches of the Yangtze River, China, employing three distinct rice cultivars and seven disparate sowing periods spanning 2019 to 2021. The objective of assessing the impact of sowing date on apparent radiation use efficiency (RUEA), accumulated temperature use efficiencies (TUE), and overall rice yield. Subsequent to the delay of sowing dates, the duration of the comprehensive growth period initially exhibited a declining trajectory before subsequently escalating, with the reduction predominantly ascribed to a decrease in the number of days preceding heading. Furthermore, there was a tendency for both the mean daily and effective cumulative solar radiation to decline over the course of the growing period. The yield of the three rice varieties demonstrated an initial surge, which was then followed by a subsequent decline in reaction to the delay of sowing dates. A correlation analysis disclosed that solar radiation and effective cumulative temperature (EAT) were the predominant elements impacting grain yield. The outcomes of the path analysis indicate that EAT exerts the most substantial influence on yield, succeeded by cumulative total solar radiation (TSR), while photothermal quotient (PTQ) demonstrates the least impact on yield. There was a significant positive correlation between EAT and cumulative TSR with spikelets per panicle (0.237** and 0.218**), grain filling (0.753** and 0.576**), and grain weight (0.339** and 0.359**), respectively. The findings of this study indicate that an increase in yield is facilitated when the EAT after heading exceeds 594.9 ℃, the EAT surpasses 2016.7 ℃, the cumulative TSR before heading is above 1548.7 MJ m− 2, the cumulative TSR after heading is over 603.0 MJ m− 2, and the cumulative total radiation throughout the entire growth period is more than 2151.8 MJ m− 2. Furthermore, the most optimal sowing date, as identified by this study, is June 6. This study provides key insights into boosting rice productivity in the middle and lower reaches of the Yangtze River, China by analyzing the impact of temperature and solar radiation on yield and identifying optimal growth conditions.Clinical trial number Not applicable.

Multiple resistance to pirimiphos-methyl and bifenthrin in Tribolium castaneum involves the activity of lipases, esterases, and laccase2

Identifying the genetic architecture of complex traits is important to many geneticists, including those interested in human disease, plant and animal breeding, and evolutionary genetics. Advances in sequencing technology and statistical methods for genome-wide association studies have allowed for the identification of more variants with smaller effect sizes, however, many of these identified polymorphisms fail to be replicated in subsequent studies. In addition to sampling variation, this failure to replicate reflects the complexities introduced by factors including environmental variation, genetic background, and differences in allele frequencies among populations. Using Drosophila melanogaster wing shape, we ask if we can replicate allelic effects of polymorphisms first identified in a genome-wide association studies in three genes: dachsous, extra-macrochaete, and neuralized, using artificial selection in the lab, and bulk segregant mapping in natural populations. We demonstrate that multivariate wing shape changes associated with these genes are aligned with major axes of phenotypic and genetic variation in natural populations. Following seven generations of artificial selection along the dachsous shape change vector, we observe genetic differentiation of variants in dachsous and genomic regions containing other genes in the hippo signaling pathway. This suggests a shared direction of effects within a developmental network. We also performed artificial selection with the extra-macrochaete shape change vector, which is not a part of the hippo signaling network, but showed a largely shared direction of effects. The response to selection along the emc vector was similar to that of dachsous, suggesting that the available genetic diversity of a population, summarized by the genetic (co)variance matrix (G), influenced alleles captured by selection. Despite the success with artificial selection, bulk segregant analysis using natural populations did not detect these same variants, likely due to the contribution of environmental variation and low minor allele frequencies, coupled with small effect sizes of the contributing variants.

The mechanism by which a clock gene pleiotropically controlling life history and behavioral traits causes reproductive isolation is explained using a model species, the melon fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae). Melon flies mate once a day, at dusk. The population selected for life history traits exhibits correlated responses in the time of mating during the day. For example, the fly populations selected for faster (slower) development have an earlier (later) time of mating. A circadian rhythm controls the time of mating. The circadian periods in constant darkness were about 22 h in lines selected for a short developmental period and about 31 h in lines selected for a long developmental period. The data on crosses between the selected lines indicated that the developmental period is controlled by a polygene, whereas the circadian period may be controlled by a single clock gene. These results suggest a clock gene pleiotropically controls developmental and circadian periods in the melon fly. Reproductive isolation may often evolve as an indirect (pleiotropic) consequence of adaptation to different environments or habitats. For example, niches that are temporally or seasonally offset can select organisms with different developmental characteristics. These developmental differences can inadvertently cause reproductive isolation by a variety of means including shifts in mating activity patterns. The difference in time of mating between populations selected for developmental period translated into significant prezygotic isolation, as measured by mate choice tests. If the mating time between populations differed more than 1 h, the isolation index was significantly higher than zero. These findings indicate that premating isolation can be established by a pleiotropic effect of a clock gene. There are many examples in which the difference in timing of reproduction prevents gene flow between populations, such as the egg spawning time in marine organisms, the flowering time in angiosperms, and the time of mating in insects. In such organisms, if genetic correlations between circadian rhythm and reproductive traits exist, multifarious divergent selection for life history traits would often accelerate the evolution of reproductive isolation through clock genes. Natural populations may diverge in reproduction time through drift, direct natural selection for time of reproduction, or as a by‐product effect of genetic correlations. In any case, clock genes are keys in reproductive isolation.

We evaluated the thermal adaptations of embryos of 6 terrestrial hermit crab species in the family Coenobitidae (genera Birgus and Coenobita): B. latro, C. brevimanus, C. cavipes, C. purpureus, C. rugosus, and C. violascens. Embryos of each species were cultured in vitro at 6 dif- ferent temperatures (18 to 34°C) in artificial seawater to avoid air desiccation; the lower threshold temperatures for embryonic development were estimated using heat summation theory equa- tions. Additionally, partial effective cumulative temperatures (> lower threshold temperature) until hatching were determined for ovigerous females of each species cultured in containers. The relationships between the embryonic growth index values (relative area of the embryonic body vs. total embryo surface) and effective cumulative temperatures were expressed using cubic equa- tions. Lower threshold temperature was estimated to be 12.7 to 14.5°C. The effective cumulative temperature and egg incubation period estimates from the appearance of the embryonic body to hatching were higher in B. latro and C. brevimanus, followed by C. rugosus, C. cavipes, and C. violascens, and lower in C. purpureus, suggesting that C. brevimanus may retain an ancestral thermal adaptation trait for embryos, as in B. latro, which is considered the most ancestral species in the coenobitid phylogeny. Egg size varied among species but did not affect the thermal adap- tations of embryos. The lower effective cumulative temperature and shorter egg incubation period may be advantageous to producing broods during the shorter summer breeding season in C. pur- pureus, which has the northern-most geographical distribution.

Sugarcane is a globally significant economic crop, and sugar content is a key determinant of its financial and industrial value. This study utilized sugar content information from spring-planted and ratoon sugarcane in six research regions across Guangxi, China from 2008 to 2023 along with concurrent meteorological data. By conducting statistical tests, the critical meteorological factors influencing the sugar content of sugarcane (effective cumulative temperature and rainfall) were identified. These factors were then used as independent variables to construct a vector autoregression (VAR) model, which was employed to analyze the spatiotemporal dynamic relationships between sugar content and meteorological variables across different planting periods. The empirical results demonstrated that the influence of effective cumulative temperature on sugar content across various regions and planting periods shifted from positive to negative in the short-term, eventually reverting to a positive effect after a period of alternating influences. The impact of rainfall mirrored effective cumulative temperature, though it was relatively less pronounced. The sugarcane in Nanning and Baise was less influenced by effective cumulative temperature and rainfall, with the short-term impact changing from positive to negative and diminishing over time. Our findings provide scientific insights for guiding the ecosystem management of sugarcane in China.

In this study, protein content (PC) of brown rice before harvest was established by remote sensing (RS) and analyzed to select the key management factors that cause variation of PC using a GIS database. The possibility of finding out the key management factors using GreenNDVI was tested by combining RS and a GIS database. The study site was located at Yagi basin (Japan) and PC for seven districts (85 fields) in 2006 and nine districts (73 fields) in 2007 was investigated by a rice grain taste analyzer. There was spatial variability between districts and temporal variability within the same fields. PC was predicted by the average of GreenNDVI at sampling points (Point GreenNDVI) and in the field (Field GreenNDVI). The accuracy of the Point GreenNDVI model (r 2 > 0.424, RMSE < 0.256%) was better than for the Field GreenNDVI model (r 2 > 0.250, RMSE < 0.298%). A general-purpose model (r 2 = 0.392, RMSE = 0.255%) was established using 2 years data. In the GIS database, PC was separated into two parts to compare the difference in PC between the upper (mean + 0.5SD) and lower (mean − 0.5SD) parts. Differences in PC were significant depending on the effective cumulative temperature (ECT) from transplanting to harvest (Factor 4) in 2007 but not in 2006. Because of the difference in ECT depending on vegetation term (from transplanting to sampling), PC was separated into two groups based on the mean value of ECT as the upper (UMECT) and lower (LMECT) groups. In 2007, there were significant differences in PC at LMECT group between upper and lower parts depending on the ECT from transplanting to last top-dressing (Factor 2), the amount of nitrogen fertilizer at top-dressing (Factor 3) and Factor 4. When the farmers would have changed their field management, it would have been possible to decrease protein contents. Using the combination of RS and GIS in 2006, it was possible to select the key management factor by the difference in the Field GreenNDVI.

Two replicate lines of the melon fly, Bactrocera cucurbitae , were selected for short or long developmental periods. The lines selected for long developmental periods responded positively to the selection, and selection for short developmental periods showed only a slight response. The responses to selection for long developmental periods were caused mainly by change in the larval period rather than in the pupal period. The comparisons of adult body sizes and survival rate before emergence showed that longer developmental periods were associated with larger adults, but also with lower survival rates during larval and pupal stages. These results are discussed in relation to the sterile insect technique in the melon fly.

水稲冷害の早期警戒システムにおいて東北全域の生育監視に適用する止葉展開期までの発育ステージを葉齢で予測するモデルを作成した.本モデルでは, 主稈葉齢が1進むのに必要な10～24℃の有効積算気温を出葉間隔とした.葉齢増加による出葉間隔の転換点を主稈葉齢9.1と11.1とし, 3時期に分割した.出葉間隔はPhase Iは一定, Phase IIでは一定の割合で拡大し, Phase IIIで再び一定とする.葉齢は出葉間隔に基づいて, 日々の葉齢進度を積算して推定する.東北の基幹12品種のうち, 1997年と1998年の7品種の盛岡における出葉経過からモデルのパラメータを決定した.本モデルによる推定葉齢と実測葉齢を1999年の盛岡について比較すると, 「おきにいり」を除いた11品種で誤差平均が0.25葉, 日数に換算すると1.7日であった.作成したモデルを宮城県松山町と山形県最上町の農家圃場で検証したところ, 予測精度は比較的高かった.ただし, 出葉間隔は分げつの影響も受けるため, 初期に分げつ形成が旺盛な生育型では予測精度が低くなった.

Inter- and intrasexual selection are often assumed to push phenotypes in similar directions, but this must not always be the case. The current study used two artificial selection treatments in an attempt to disentangle the effects of inter- and intrasexual selection in the guppy (Poecilia reticulata). The first artificial treatment (inter) was maintained by selecting males that were most appealing to prospective females; in the second treatment (intra), only the most dominant males were allowed to reproduce. Male morphology, aggression, and reproductive behaviour, as well as female choice and reproductive behaviour were compared between intra- and inter-treatment. After three generations of artificial selection, inter-males varied more in their orange colouration pattern than did intra-males. This may indicate that male orange colouration is subject to negative frequency dependent selection by means of female choice in the inter-treatment. Females preferred inter-males, regardless of their own selection history. These results question the seldom tested assumption that intra- and intersexual selection reinforce the same characters. The lack of direct benefits for choosing a dominant male are hypothesized to be at the basis of this discrepancy, since male guppies do not defend territories and do not provide resources to mates.