| The result indicate: Hemiberlesia pitysophila Takagi has four generations annually, overlapping generations, not obvious over-wintering generation, the population of the winter is major at 2 instar, every instar rate in the population is 1 instars nymph 26.92%, 2 instar nymphy 47.47%, male adult and pupa 12.35%, female adult 13.26%. At winter occasionally can see the active nymphy in the woods. But at winter does not observed the obvious dispersal at the pine forest .Every generation's active nymphy occur four peak at forest is during the last ten days of March to the middle ten days of April, the first ten days of June to the last ten days of June, the last ten days of July to the first ten days of August, the last ten days of September to the second ten days of November. The first generation and the second generation can observed obvious population peak, but the third generation and the fourth generation overlapping is common. At woods the winter population's the average mortality 1 instar nymphy's is 27.83%, 2 instar nymphy32.35%, female nymphy 19.04%,male nymphy and pupa 11.42%, female adult 9.67%. At woods the whole year's the average mortality 1 instar nymphy's is 49.67%, 2 instar nymphy51.76%, female nymphy 42.25%,male nymphy and pupa 27.08%, female adult 36.33%. The population's mortality is 43.64%. The whole year average ratio of the female and the male is 2.05 : 1 at the woods. The first generation's sexual rate is 2.97 .' 1, the summer s generation's 1.77 : l,the fourth generation's 1.69 : 1. the quantity of each instar nymphy's food hasn't significant difference. The first generation female adult laid eggs' number and it's embryos' number haven't significant difference, we can forecast the first generation population dynamic depending on the number embryo of the female adult. From March to July the density is biggest, the trees is the seriously endanger.The 1 instar nymphy has three growth stages: paralysis stage, active and distribute stage, fix and grow stage. When the eggs hatch, the nymphy is the paralysis stage at the moment. This stage the 1 instar nymphy is still lie inside of the scale. Pass this stage, the nymphy change very alacrity, climb out the scale and move everywhere. This stage nymphy called the active or distributed nymphy. This stage can't be longer 76 hours, average is 18 hours. At this stage it must fix and start to take the food, and enter the third stage, otherwise it would be die. The mortality of the alacrity nymphy is usually Very heavy, inside room the mortality is 45.5%, fixed rate is 51.2% on the host plant. The first generation out hull time most at 10:00 A.M. and 2:00 P.M., each occupy the whole day's 25%, but at the first ten days of July and the first ten days of August, the second generation andthe third generation, if it's hot, outs hull high peak in advanced 8:00 A.M., overcast cloudy day, prolong 3-4:00 P.M., and the rainy day generally not outsides hull; When winter temperature is lower, woods still find some active nymphy. The breeze have not the influence on the active nymphy fixing. The active nymphy physically crawl along the distance can't exceed 30-60 cm, the distance be influenced by the temperature, the temperature is more the high activity is more distance. Cone top 100% is male scale insect and new branch needle leaf top 99.6% is male scale insect. The choice feeding of the Hemberlesia pitysophila Takagi indict P.elliottii have significant anti-insect.the armoured scale insect like to eat Pinus massoniana and P.thunbergii.Female adult have 10-15 days ex-period of laying eggs after overig the tailed. Coming into period of the laying eggs minimal is 8 days, much 1 month is above. Female adult's tallest laid 137 eggs, lowest 72 eggs, average lay 93 eggs. It has an ex-period of mature sex, at that time the male haven't sexual behavior reaction on it. The same female which have embryos also can't cause the sexual behavior reaction. Virgin female scale insect can cause the sexual behavior reaction, but can't succeed the to mate the behavior. Femal... |
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