Occurrence Regularity and Life History of Cigarette Beetle Lasioderrma serricorne(Fabricius)in Tobacco Leaf Threshing and Redrying Workshop

[Objectives]The paper was to study the occurrence regularity and life history of cigarette beetle Lasioderrma serricorne(Fabricius)in tobacco leaf threshing and redrying workshop.[Methods]With the tobacco leaf threshing and redrying workshop as the survey site,the occurrence regularity of L.serricorne was investigated,and the life history table was inferred according to its biological characteristics.The temperature,humidity and duration of tobacco leaf threshing and redrying were simulated in the laboratory to study the survival rate of all states of L.serricorne in this environment.[Results]The lifecycle of L.serricorne in tobacco leaf threshing and redrying workshop was:the overwintering generation pupated in late February;the pupa began to emerge in early March,and reached its peak in late March.The first-generation eggs started hatching in late March,pupated in late May,emerged in early June,and reached the peak eclosion of the first-generation adults in mid-July.The second-generation eggs began to hatch in late July,pupated in mid-August,emerged in late August,and reached the peak eclosion of the second-generation adults in mid-September.The third-generation eggs began to hatch in mid-September;most of the larvae began to overwinter,some pupated in mid-November and survived the winter as pupae,and some pupae emerged to adults.The survival test results of different states of L.serricorne under simulated temperature,humidity and duration in the tobacco leaf threshing and redrying process showed that the mortality rates of eggs in simulated 1,2 and 3 conditions were about 51.22%,90.24% and 100%,and the mortalities of larvae in simulated 1,2 and 3 conditions were about 18.30%,81.25%and 100%,respectively.The mortalities of pupae in simulated 1,2 and 3 conditions were about 69.39%,100% and 100%,and the mortalities of adults in simulated 1,2 and 3 conditions were about 100%,100% and 100%,respectively.[Conclusions]L.serricorne of different states can be killed by appropriately raising the temperature during threshing and redrying.

Quality Evaluation of Threshing and Redrying Process Based on Analytic Hierarchy Process

Improving the stability of the homogenization process to achieve the homogeneity of tobacco products is one of important targets for the redrying industry.According to the specification for threshing and redrying process,a total of 14 indicators in three categories that affect the quality of the threshing and redrying process were selected.Using analytic hierarchy process,combined with expert experiences,a judgment matrix was constructed to conduct consistency test.The weights of indices in production were obtained.This will help in evaluating the actual production quality,finding the weak links of process and adjusting the parameters of the corresponding links in a targeted manner,thereby improving the quality of production process.

Study on Quality Improvement of Flue-cured Tobacco by Threshing and Pneumatic Separation

This study was conducted to further classify threshed strips, so as to broaden the usable range of raw material and facilitate the effective utilization of to- bacco resource. During the threshing and redwing process, various process param- eters including the rotating speeds of threshing drums of threshing machioe, draught fans and fling drums were scientifically and rationally set according to the actual quality of the raw material. According to the characteristic that strips with close in- herent quality have basically the same specific gravity and leaf thickness, the strips from each discharge hole were accurately evaluated, and classified, followed by redrying and packaging. The results showed that the threshing and separating pro- cedure could improve the separating effect and precision according to tobacco qual- ity, so as to satisfy the separation and classification requirements for tobacco.