The Ca^(2+)/CaN/ACC and cAMP/PKA/HK signal pathways are required for PBAN-mediated sex pheromone biosynthesis in Conogethes punctiferalis

Conogethes punctiferalis is a crop and fruit pest that has caused serious economic losses to agricultural production.This pest relies heavily on its sex pheromone to ensure sexual encounters and subsequent mating success.However,the molecular mechanism underlying sex pheromone biosynthesis in this species remains elusive.The present study investigated the detailed mechanism underlying PBAN-regulated sex pheromone biosynthesis in C.punctiferalis by transcriptome sequencing of the C.punctiferalis pheromone glands(PGs)and subsequent functional identification of the target genes.The results showed that female mating started from the first scotophase,and peaked at the second to fifth scotophases in accordance with the release of sex pheromones.PBAN regulated sex pheromone biosynthesis by employing Ca^(2+)and cAMP as secondary messengers,as demonstrated by RNA interference(RNAi),pharmacological inhibitors,and behavioral assays.Further investigation revealed that calcineurin(CaN)and acetyl-CoA carboxylase(ACC)were activated by PBAN/Ca^(2+)signaling,and the RNAimediated knockdown of CaN and ACC transcripts significantly reduced sex pheromone production,ultimately leading to a significantly reduced ability of females to attract males.Importantly,hexokinase(HK)was found to regulate sex pheromone biosynthesis in response to the PBAN/cAMP/PKA signaling pathway,as demonstrated by RNAi,enzyme activity,and pharmacological inhibitor assays.Furthermore,Far2 and Desaturase1 were found to participate in PBAN-regulated sex pheromone biosynthesis.Altogether,our findings revealed that PBAN regulates sex pheromone biosynthesis through the PBANR/Ca^(2+)/CaN/ACC and PBANR/cAMP/PKA/HK pathways in C.punctiferalis,which enriches our comprehension of the details of sex pheromone biosynthesis in moths.

Molecular Taxonomy of Conogethes punctiferalis and Conogethes pinicolalis(Lepidoptera: Crambidae) Based on Mitochondrial DNA Sequences

Conogethes punctiferalis（Guenée）（Lepidoptera： Crambidae） was originally considered as one species with fruit-feeding type（FFT） and pinaceae-feeding type（PFT）, but it has subsequently been divided into two different species of Conogethes punctiferalis and Conogethes pinicolalis. The relationship between the two species was investigated by phylogenetic reconstruction using maximum-likelihood（ML） parameter estimations. The phylogenetic tree and network were constructed based upon sequence data from concatenation of three genes of mitochondrial cytochrome c oxidase subunits I, II and cytochrome b which were derived from 118 samples of C. punctiferalis and 24 samples of C. pinicolalis. The phylogenetic tree and network showed that conspecific sequences were clustering together despite intraspecific variability. Here we report the results of a combined analysis of mitochondrial DNA sequences from three genes and morphological data representing powerful evidence that C. pinicolalisand C. punctiferalis are significantly different.

Effects of photoperiod and temperature on diapause induction in Conogethes punctiferalis （Lepidoptera： Pyralidae）

The yellow peach moth, Conogethes punctiferalis （Guenee）, a multivoltine species that overwinters as diapausing larvae, is one of the most serious insect pests on maize in China. Effect of photoperiod and temperature on larval diapause was examined under empirical laboratory conditions. Short-day treatments caused larval diapause at 25℃, and the critical photoperiod was between 12 and 13 h （or 12 h 51 min） light per day. No sensitive instar was identified for diapause induction under alternated short- （L ： D 11 ： 13 h） and long-day （L ： D 14 ： 10 h） treatments at different larval stages. However, accumulative treatment of three instars and 10 d under short-day treatment was required for the induction of 50% larval diapause. All larvae entered diapause at 20℃, whereas less than 3% did so at 30℃, irrespective of the long- or short-day treatment. Furthermore, under the short-day treatment, more than 90% of larvae went into diapause with temperatures ≤ 25℃, but less than 17% did so at 28℃. In contrast, under the long-day treatment, less than 19% of larvae went into diapause with temperatures ≥23 ℃. The forward shift （5℃） of critical temperature under the long-day regime demonstrated the compensatory effect of temperature and photoperiod on diapause induction. In conclusion, C. punctiferalis had a temperature-dependent type Ⅰ photoperiodic diapause response; there was no sensitive instar for diapause determination, but the photoperiodic accumulation time countermeasures both of the short-day cycles and the number ofinstars exposed, and the photoperiodic diapause response, was a temperature-compensated phenomenon.

桃蛀螟在广西莪术上的发生危害规律及防治研究

研究了桃蛀螟（Conogethes punctiferalis）的为害特性与田间药剂及诱集植物的防治效果。结果表明,桃蛀螟从心叶开始自上而下钻蛀为害广西莪术（Cureuma kwangsiensis）茎部,7-9月为全年为害高峰期;供试的6种药剂中20%氯虫苯甲酰胺悬浮剂、2.5%三氟氯氰菊酯乳油防效较好,分别为76.52%、71.62%;种植诱集植物红球姜并辅以使用1次氯虫苯甲酰胺,受害株率减少93.71%,虫口减退率96.21%。

不同寄主植物对桃蛀螟解毒酶活性的影响

在室内条件下,对桃蛀螟(Conogethes punctiferalis)幼虫取食桃(Amygdalus persica)、向日葵(Helianthus annuus)、棉花(Gossypium spp)、大豆(Glycine max)、蓖麻(Ricinus communis)、柿(Diospyros kaki)、玉米(Zea mays)、高粱(Sorghum bicolor)、无花果(Ficus carica)9种寄主植物后的磷酸酯酶、谷胱甘肽-S-转移酶和乙酰胆碱酯酶的活性进行了研究。结果表明,不同寄主植物对桃蛀螟幼虫磷酸酯酶、乙酰胆碱酯酶和谷胱甘肽-S-转移酶活性均有显著的影响。