Pattern Of Co-parasitism Both Hemiberlesia Pitysophila And Pestalotiopsis Funereal And Its Effects On The Main Chemical Substances In Masson Pine Needle

Based on the first discovery of co-parasitism both the dangerous and invasive pine armored scale, Hemiberlesia pitysophila, and the native wide-distributed fungi, Pestalotiopsis funereal, the pattern of this co-parasitism and its effects on the main chemical substances contented in Masson Pine needles were investigated and measured, aimed to explore the mechanism of the invasive pine armored scale in South China, in the pine forest located at Fuqing of Fujian Province in 2010. Results showed that around 50% of pine needles infested with the pine armored scale were co-parasitized by the fungi of P. funereal. In the period from June to October while the pine armored scale population kept the lowest level in a year cycle, densities of the total individuals including dead scales and live individuals, live individuals, and percentage of the needles with live individuals of the pine armored scale in co-parasitic needles were all significantly higher than those in non-co-parasitic needles. These aspects imply that the co-parasitism of both H. pitysophila and P. funereal is prevalent in the pine forest invaded with H. pitysophila, and can be beneficial to the scale pest's occurrence and adaptation to a new habitat. Additionally, biological test experiments showed that the co-parasitism significantly increased the main chemical substances of the pine needles, including water content with a 9.99% of mean increment, chlorophyll a with a 29.36% of mean increment, total chlorophyll with a 34.63% of mean increment, water-soluble sugar with a 143.60% of mean increment, polysaccharide with a 11.51% of mean increment, protein with a 34.93% of mean increment, tannin with a 39.29% of mean increment and total hydroxybenzene with a 45.54% of mean increment. Based on the results above, we suggest that the co-parasitism both H. pitysophila and P. funereal could induce a altruistic efficacy to the pine armored scale through increasing the main nutrimental substances in needles, however, it also could induce a resistant efficacy against the pine armored scale through increasing the tanning and hydroxybenzene contents in needles. So the present co-parasitic pattern in the field could result from their common action of both the two efficacies. Furthermore, the suggestion reveals that the co-parasitism could play an important role in the invasion and outbreak course of H. pitysophila population in South China. It is greatly helpful for clarifying the invasive mechanism of H. pitysophila to further study the co-parasitism's ecological functions and results.