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71.
稻秆潜蝇在重庆市巳由次要害虫上升为主要害虫,该虫在重庆地区1年发生3代,以第3代幼虫越冬。越冬代.幼虫在3月下旬化蛹,4月中旬至下旬为第1代成虫期,5月上旬为产卵期。5月上旬至6月上旬为第1代幼虫期,6月上旬至下旬为蛹期。第2代成虫期为6月下旬至7月中旬,7月上、中旬为产卵期,7月中旬至8月上旬为幼虫期,8月上旬至下旬为蛹期。第3代成虫期为9月上旬至下旬,并迁至越冬寄主上产卵,10月初至11月底孵化为幼虫进入越冬期。成虫羽化后1—2h即可交配,但多数于羽化后1—3d才交配。更尾后越冬代于4—9d,第2代于3—7d后产卵,一般1叶仅产1卵,偶有数粒。单雌产卵量2—81粒不等。成虫寿命为20d左右。  相似文献   
72.
为探究新冠疫情对消费者畜禽产品购买偏好的影响,本研究运用选择实验的方法,基于网络问卷形式获得湖北武汉、河南郑州、湖南长沙、浙江杭州4个城市934位消费者行为数据,采用混合logit模型进行数据分析。结果表明:从区域上看,不同区域消费者对线上渠道偏好存在差异,相对于轻度疫情区域,重度疫情区域的消费者对线上渠道偏好显著,对时间成本负向偏好明显,且对各属性的支付意愿均较高;从产品上看,消费者对不同产品的支付意愿存在差异,对具有品牌属性的产品支付意愿最高,可追溯信息属性次之,且同一区域内猪肉的支付意愿高于鸡肉。因此,畜禽产品零售企业应促进线上线下协同发力,提高效率吸引消费者;加强与完善可追溯畜禽产品的品牌建设;合理细分产品和区域,逐步拓展可追溯产品市场。  相似文献   
73.
为了解家蚕雌蛾交配时间早迟与产卵的关系,对家蚕雌蛾羽化后1~5h交配对产卵速度、产卵量和卵质的影响进行了研究,结果表明:雌蛾羽化后4~5h交配的雌蛾产卵速度快、产卵量最多、不良卵最少。  相似文献   
74.
ARC and ND colony were obtained by rearing the whitebacked planthopper (WBPH), Sogatella furcifera(Horvath), exclusively on ARC10239 (ARC, carrying resistance gene Wbph2) and N‘Diang Marie (ND, carrying resistance gene WbphS) till 15 generations. Taichung Native 1 (TN1) and Rathu Heenati (RHT) served as susceptible and resistant check, respectively. The results of electronic recording revealed that duration of salivation and X-waveform of the two colonies on their corresponding hosts was short while the duration of phloem ingestion was long. The amount of honeydew excreted by ARC and ND colony did not differ on their corresponding host varieties from TN1 and was much higher than that of RHT. The number of eggs laid on their host varieties and TN1 were significantly higher than that on RHT. No distinct change was observed for these two colonies in term of percentage of developed eggs. The nymph survival rate of ND colony on its selection host was 45.0%, significantly different from that on TN1(71.4%0) and RHT(21.0%), while that of ARCcolony was 68. 3%, not significantly different from that on TN1(77.5%), but much higher than that on RHT(22.6%).The nymphal development duration of these two colonies on the corresponding hosts was not different from that on TN1, but significantly shorter than that on RHT. In brief, these two colonies had almost adapted to their corresponding host varieties based on feeding and oviposition, but the nymphal survival rate of ND colony was still low.  相似文献   
75.
在温度(25±1)℃,光暗周期L:D=14:10(光期06:00开始,20:00结束),相对湿度RH=75%-80%的条件下,观察了麻楝蛀斑螟成虫的羽化与生殖行为.结果表明:成虫羽化率85.4%,羽化期25d左右;羽化行为主要出现在暗期,日羽化高峰在20:00-23:00,占总羽化量的80.7%;雌、雄比例0.83:1.羽化后第2天达到性成熟,当天羽化的成虫未发生交配;交配发生在进入暗期5-8h,交配持续时间50—200min;随着日龄的增大,交配率降低,交配持续时间增长;交配后第2天开始产卵;雌、雄虫均未发现2次交配现象.交配雌虫平均产卵104粒,卵期7d左右,孵化率84.3%;未交配雌虫平均产卵157粒,孵化率0.交配雌虫和雄虫的平均寿命为3.73和2.93d,未交配雌虫和雄虫的平均寿命为5.87和5.03d.  相似文献   
76.
Using scanning electron microscopy, we investigated the distribution of the trichoid, basiconic, and coeloconic sensilla on the antennae of the diamondback moth (DBM;Plutella xylostella). The trichoid sensilla were the most abundant sensory organ, and the male moth antennae host signiifcantly more trichoid sensilla than female moth antennae. Conversely, basiconic and coeloconic sensilla were found more frequently on female than on male antennae. We performed experiments with various degrees of antennal ablation and demonstrated that DBM antennae played a key role in the control of mating and oviposition. We found that neither oviposition preference nor mating behaviors changed signiifcantly when less than 1/4 of both antennae were removed. However, there was a signiifcant behavioral change when the antennae were ablated by more than half. As the length of the antenna was shortened, the successful mating rate decreased and mating peak was delayed. An otherwise consistent host preference for oviposition was eliminated when both antennae were completely removed. Furthermore, we found that the number of trichoid sensilla was positively correlated with mating rate and oviposition preference. However, the numbers of basiconic and coeloconic sensilla were not correlated with mating rate and mating peak, but highly correlated with oviposition preference. Taken together, our results indicate that antennal sensory information plays a critical role in the mating and oviposition behaviors of this economically important pest.  相似文献   
77.
Abstract –  The European bitterling is a freshwater fish with an unusual spawning symbiosis with freshwater mussels. Female bitterling possess long ovipositors that they use to place their eggs onto the gills of a mussel. Males fertilise the eggs by releasing sperm into the inhalant siphon of the mussel. The embryos develop inside the mussel for approximately a month, eventually leaving the mussel as actively swimming larvae. Because they use a discrete spawning site that can be readily manipulated they represent an ideal model for linking reproductive decisions with population dynamics. Bitterling have been used in field and large-scale pool experiments, in combination with modelling and population and genetic studies to investigate the population consequences of behaviour. Here we show how male mating tactics, female mate and oviposition decisions, and aggressive interference competition among juveniles, may have significant impacts on bitterling population size and population genetics.  相似文献   
78.
为比较杨小舟蛾对不同寄主的选择差异性,利用生物观察法研究了该成虫在5种黑杨无性系寄主间的停靠选择行为和产卵选择行为,验证了5种寄主挥发物对该虫进行寄主选择过程产生的作用。结果表明:不同性别、不同生理状态的成虫对5种寄主的选择率存在差异;雌性个体无论是否交配均表现出对5种样本相同的差异性选择,而雄性个体则未表现出这种选择差异性。在相同虫数下,有更多的交配后雌蛾对寄主做出了选择,与未交配雌蛾选择虫数相比差异显著。杨小舟蛾对碧玉杨的寄主产卵选择性最强,108杨次之,与对照差异显著;其余处理与对照差异不显著。  相似文献   
79.
We determined the effects of petroleum spray oil (PSO) (Caltex Canopy®) on oviposition responses of Helicoverpa armigera Hubner and Ostrinia nubilalis Hubner adults, and larval survival of the pest moths on cotton and maize plants in the laboratory. Application of 2% (v/v) of the PSO deterred H. armigera oviposition. Increasing the rate from 2 to 5% (v/v) did not significantly reduce the number of eggs laid by H. armigera on the treated plants. In contrast, the minimum rate at which the oil could deter oviposition of O. nubilalis on maize plants was 5% (v/v). Increasing the rate from 5 to 10% (v/v) did not significantly reduce the number of eggs laid per plant. However, a reduction in the rate of the PSO from 5 to 3% (v/v) resulted in a 73.9% increase in oviposition activity on the maize plants. In wind tunnel bioassay tests, all mated H. armigera females tested could detect and settle on plants treated with water but with plants treated with PSO at various times, only 50% of tested females settled on the plants 4?–?5 days after treatment (DAT) and none on the plants 0?–?2 DAT. A solid phase micro-extraction (SPME) test to determine the effect of the PSO on volatiles released by the cotton plants showed that the quantity of volatiles released by the cotton plants treated with PSO was lower than for water treated plants. This indicates that the PSO sprays may be suppressing or masking the leaf surface volatiles of the cotton plants, thereby deterring oviposition of H. armigera. Larval survival data show that PSO sprays can cause direct mortality of first, second and third instar O. nubilalis larvae. PSOs may have the potential to be integrated into pest management programme targeting H. armigera and O. nubilalis on cotton and maize crops, respectively.  相似文献   
80.
小菜蛾产卵对寄主的选择性及其应用初步研究   总被引:8,自引:0,他引:8  
以广州,深圳种植的几种主要十字花科蔬菜,研究了小菜蛾对寄主的选择性,室内试验和田间调查结果基本一致,小菜蛾对芥菜,菜心的嗜好性最大,对萝卜,白菜次之,对芥蓝,花椰菜最差,根据小菜蛾喜受在芥菜上产卵这一特性,进行了芥菜与芥蓝套种诱集防治小菜蛾的田间试验,结果表明,所有套种田中芥蓝上的小菜蛾卵数量都显著低于单种田(P〈0.05),在芥蓝生长后期,单种田芥蓝中卵数量高出套田近10倍,芥菜中数量是芥蓝中的  相似文献   
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