Eight kinds of phytoecdysteroids extracted from different parts of Ajuga multiflora Bunge (Labiatae) that were collected from different places at different time were tested for killing effects on the 2-instar larvae o...Eight kinds of phytoecdysteroids extracted from different parts of Ajuga multiflora Bunge (Labiatae) that were collected from different places at different time were tested for killing effects on the 2-instar larvae of Cryptorrhynchus lapathi L by adding them to the artificial diet of larvae. The experimental results indicated that adding 1-3-mL phytoecdysteroids to the artificial diet could lead 58%-100% of 2-instar larvae of C. lapathi to death within 24 days. The phytoecdysteroids extracted from the whole plant of A. multiflora which was collected before flowering time were much more effective than those extracted from the plants collected at flowering and after flowering periods, and the modified mortality rate of larvae reached 65.22%, 85.07%, and 98.11% at the dosage level of 1-mL, 2-mL, and 3-mL extracts, respectively. The extract made from root of A. multiflora plant was more effective in killing efficiency than those from stem and leaves, and the average death rates of larvae were up to 100%, 98.20% and 98.32% at dosage levels of 1-mL, 2-mL, and 3-mL extracts, respectively. The killing speed of the extracted phytoecdysteroids was slower than that of triflumuron, hexaflumuron or deltamethrin emulsifiable concentrate. The mortality rate of larvae is closely related to the feeding duration on the diets containing phytoecdysteroids. Feeding on the diets with addition of phytoecdysteroids for 16 days, more than 80% of treated 2-instar larvae of C. lapathi were led to death. The killing effect of the extracts was little affected by the growth areas of A. multiflora plant and the adding way to artificial diet.展开更多
The behavior of osier weevil’s adult was studied at Lindian County in Heilongjiang Provillce in 1987-90. Osier weevil started emergence in the last ten days in July and peaked in the tirst and second ten days in Augu...The behavior of osier weevil’s adult was studied at Lindian County in Heilongjiang Provillce in 1987-90. Osier weevil started emergence in the last ten days in July and peaked in the tirst and second ten days in August. Emergence on the susceptible species, such as Populus berolinensis, is 5 to 10 days earlier than that on the species of pest-resistance such as P. xiaohei. The adult move slowly, and it spreads or distributes mainly by crawling or by carrying of human beings. Osier weevil has a selection on host species tbr intake nourishment. According to the degree of being addicted, the series can be arranged as Populus berolinensis. Populus staline, Populus pesudo simonii× nigra,Populus xiaohei, Populus pachermis. The adult is likely to dwell on trunks and likely to eat slender and tender branches. Osier weevil makes a choice of host plants to lay eggs. The adult laid more eggs on the P.berolinensis than on P. xiaohei or willow. Most of the eggs laid on the young trees were distributed blow 2 m height. As tree’s age increase, the eggs’ spots get higher and higher. The eggs laid on the eastern and the southern sides of ti1e trunk are more than that laid on the West and the North. P.berolinensis and P. staline are the source trees of osier weevil in artificial Stands in Western Heilongjiang. Cutting the pest source tree, planting pest-resistance species, strengthening the quarantine of the forest plants, and controlling of the diseases and pests timely have very important significance to prevent the occtirrence and damage of this pest.展开更多
基金This paper was supported by National Natural Science Foundation of China(39970620)the"TRAPOYT"
文摘Eight kinds of phytoecdysteroids extracted from different parts of Ajuga multiflora Bunge (Labiatae) that were collected from different places at different time were tested for killing effects on the 2-instar larvae of Cryptorrhynchus lapathi L by adding them to the artificial diet of larvae. The experimental results indicated that adding 1-3-mL phytoecdysteroids to the artificial diet could lead 58%-100% of 2-instar larvae of C. lapathi to death within 24 days. The phytoecdysteroids extracted from the whole plant of A. multiflora which was collected before flowering time were much more effective than those extracted from the plants collected at flowering and after flowering periods, and the modified mortality rate of larvae reached 65.22%, 85.07%, and 98.11% at the dosage level of 1-mL, 2-mL, and 3-mL extracts, respectively. The extract made from root of A. multiflora plant was more effective in killing efficiency than those from stem and leaves, and the average death rates of larvae were up to 100%, 98.20% and 98.32% at dosage levels of 1-mL, 2-mL, and 3-mL extracts, respectively. The killing speed of the extracted phytoecdysteroids was slower than that of triflumuron, hexaflumuron or deltamethrin emulsifiable concentrate. The mortality rate of larvae is closely related to the feeding duration on the diets containing phytoecdysteroids. Feeding on the diets with addition of phytoecdysteroids for 16 days, more than 80% of treated 2-instar larvae of C. lapathi were led to death. The killing effect of the extracts was little affected by the growth areas of A. multiflora plant and the adding way to artificial diet.
文摘The behavior of osier weevil’s adult was studied at Lindian County in Heilongjiang Provillce in 1987-90. Osier weevil started emergence in the last ten days in July and peaked in the tirst and second ten days in August. Emergence on the susceptible species, such as Populus berolinensis, is 5 to 10 days earlier than that on the species of pest-resistance such as P. xiaohei. The adult move slowly, and it spreads or distributes mainly by crawling or by carrying of human beings. Osier weevil has a selection on host species tbr intake nourishment. According to the degree of being addicted, the series can be arranged as Populus berolinensis. Populus staline, Populus pesudo simonii× nigra,Populus xiaohei, Populus pachermis. The adult is likely to dwell on trunks and likely to eat slender and tender branches. Osier weevil makes a choice of host plants to lay eggs. The adult laid more eggs on the P.berolinensis than on P. xiaohei or willow. Most of the eggs laid on the young trees were distributed blow 2 m height. As tree’s age increase, the eggs’ spots get higher and higher. The eggs laid on the eastern and the southern sides of ti1e trunk are more than that laid on the West and the North. P.berolinensis and P. staline are the source trees of osier weevil in artificial Stands in Western Heilongjiang. Cutting the pest source tree, planting pest-resistance species, strengthening the quarantine of the forest plants, and controlling of the diseases and pests timely have very important significance to prevent the occtirrence and damage of this pest.
