| Tea is one of the three major health drinks in the world,and the quality of tea directly affects the quality of tea drink.Basilepta melanopus Lefevre is an important pest of tea plants,which leads to the decrease of yield and quality of tea and seriously endangers the sustainable and healthy development of dark tea industry in Hubei Province,the breeding of highly resistant tea cultivars is one of the most economical and effective green prevention and control technologies to control B.melanopus.In order to clarify the resistance of different tea cultivars to B.melanopus,this study investigated the population number and the dynamics of B.melanopus on five tea cultivars in Chibi City,Hubei Province,determined the morphological structures,anatomical structures and biochemical composition of the leaves of five tea cultivars,and analyzed the volatile components of five tea cultivars,observed the ultrastructures of the antennal sensilla of B.melanopus,hoping to provide basic data for the selection and breeding of tea cultivars to resistant B.melanopus.The main results of this study are as follows:1.The field population of B.melanopus on five tea cultivars were investigatedThere was a significant difference in the population number of B.melanopus on five tea cultivars.The number of insect populations in the field was:ECHA 1>Zhuyeqi>Zhongcha 108>local population>Fuding Dabai.The investigation of the various insect states of the B.melanopus by sieve soil method showed that the larvae of the B.melanopus occurred from March to early May,the adults emergence began in early May,the peak period occurred in 1st the-days of May,and the adults disappeared in mid-June.2.The volatile components of different tea cultivars were discoveredThe volatile compounds of ECHA 1,Zhuyeqi,Zhongcha 108,Fuding Dabai and local population were collected by dynamic headspace adsorption method,and the VOCs of five tea cultivars were isolated and identified by GC-MS.The results showed that a total of 7substances,D-limonene,basil,nonaldehyde,camphor,decanal,α-cedarine and longifolene,were extracted from the experimental tea trees,but the volatile compositons of different tea cultivars were different.3.The correlations between the insect resistance and the morphological structures and biochemical components in five tea cultivars were discussedThe resistance of different tea cultivars was closely related to glutamate concentration,amino acid content,free amino acid content,epicatechin gallate（ECG）,and epicatechin（EC）content.The population number on the five tea cultivars was positively correlated with glutamate concentration,amino acid content and free amino acid content,and negatively correlated with the content of epicatechin gallate（ECG）,epicatechin（EC）,epidermal thickness and leaf thickness.4.The ultrastructures of the antennal sensilla of B.melanopus was clarifiedThe total length of the antennae of males was significantly longer than females（P<0.05）,antennal segments F1,F2 of females significantly narrower than males（P<0.05）,it was found that 9 types of antennal sensilla of the B.melanopus were identified,namely sensillum trichoid,sensillum archaetica,sensillum basiconca,sensilla furcatea,B?hm bristles,According to the morphological characteristics of the sensor,the sensillum trichoid,the sensillum archaetica and the B?hm bristles are mainly for feeling mechanical stimulation.This study clarified the occurrence dynamics of B.melanopus in Chibi City,Hubei Province and the difference of resistance in five tea cultivars to B.melanopus,and discussed the correlations between the physicochemical traits of tea plants and the number of insect populations in the field.The results will be helpful for the accurate prevention and control of B.melanopus,which will provide a theoretical reference for the selection and breeding of resistant cultivars of tea. |
