Assessment And Control Technology Of Ecological Risk During The Field Planting Of Transgenic Phytase Maize

Therefore, this paper takes the transgenic phytase maize and its control parent Liyu-35 as the object of study, to make risk detection and monitoring on the drift and dispersal of its pollen and fruit-setting, develop risk control techniques for the natural ecology of transgenic maize based on sorghum isolation area, establish a risk probability model for pollen drift and dispersal of transgenic maize and fruit-setting, and research the growth difference between the individuals and populations of asiatic corn borer in indoor and field conditions. Based on the "four test bases" for transgenic maize located in "such three places" as Dezhou and Jiyang of Shangdong Province, and Xing’an of Guangxi Province from 2011 to 2013, a study is carried out on the control technology for the natural ecological risks to transgenic maize. The main results are as follows:(1) By setting control field and unifying farm operation, an investigation is made on the major economical characters of phytase maize in the period of plant height, ear height and loose powder, an analysis is made on the significant difference between the main nutritional ingredients of transgenic maize kernel, and a survey is made on its economic yield. The research result shows:after farm operation is unified, the plant height (H=215.3) of farm operation, compared to that of parental maize, is universally higher than that of parental maize (h=206.2); however, analysis of nutritional component shows that in phytase corn kernel, only phosphorus content is obviously higher than parental corn, increased by 29.54%, while other nutrient contents are not different (P<0.05); data analysis on the yield in 2012 and 2013 shows that there was not significant difference among the transgenic phytase maize and the contrast maize.(2) Through such research methods as field pollen staining and fruit-setting, use is made of self-made adhesive plate to inspect tinted pollen and of metaxenia phenomenon to inspect corn kernel, and a systematic study is made on the pollen dispersal distance, probability as well as effective dispersal distance and probability of phytase maize at different distances, in different azimuths and in different weather conditions. The research result shows:the risk probability of pollen drift and dispersal and fruit-setting is different in different azimuths, and it is reduced as its distance from the field where transgenic maize is planted is increased. Hereinto, the risk probability of pollen drift and dispersal is 72.7% in high-risk area (1 meter away), is 6.3% in general risk area (3 to 10 meters away), is 0.4% in low risk area (5 to 35 meters away), and is risk-free over 45 meters away. According to the risk monitoring on hybrid fructification, it’s also feasible to divide the periphery of transgenic maize-growing region into three areas, which are high-risk area (1 meter away: 9.67%), general risk area (3 to 10 meters away:2.76%) and low risk area (20 to 60 meters away:0.63%). Based on the above analysis, the effective range for the drift and dispersal of transgenic maize is 100 meters in 2012 and the data was 250 meters in 2013 and within the possible range of pollen drift and dispersal, the probability of hybrid fructification is lower.(3) By setting prevention and control and opening parcels, a systematic study is made on whether the use of sorghum isolation area for ecological prevention and control can effectively prevent pollen from drifting and dispersing, and finally the effect of prevention and control is inspected. The research result shows:sorghum isolation area has a significant effect of prevention and control. Sorghum isolation area can reduce the dispersal distance of pollen, the probability of hybrid fructification.(4) All-weather video record probe is used to monitor the pollinating insects in the flowering period of maize and the larceners of corn in mature period, with the analytical and observation data showing:There are untold vector insects for maize in the experimental field, and the major vector insects are divided into 24 kinds,10 families and 4 orders (lepidoptera, coleopteran, hymenoptera and thysanoptera). Among them, lepidoptera falls into 12 kinds and 5 families, coleopteran falls into 6 kinds and 3 families, coleopteran falls into 5 kinds and 1 family, and thysanoptera falls into 1 kind and 1 family. Survey shows that Ostrinia furnacalis and beet armyworm, which belong in lepidoptera, are the major vector insects in the flowering period of maize. A total of nine kinds of seed stealers are found, which are field mouse, hedgehog, gopher, rock dove, cyanopica cyana, picapica, sparrow, woodpie and hare. Among them, the number of cyanopica cyana and sparrow is obviously increased by 87.5% and 37.3% in the transgenic maize field, and the total feeding time for pheasant, cyanopica cyana and sparrow are respectively increased by 516.7%,39.1% and 6.7%.(5) Through a field investigation on experimental field and a contrast between the amount of the ovum of Ostrinia furnacalis and the quantity of the plants injured by insects, and with the combination of the feeding status of different treatments and different nutritive tissues, the analysis shows:Relative to the control field, the experimental field is attacked severely by Ostrinia furnacalis; however, the feeding results of different nutritive tissues show that the stem of transgenic maize is most conducive to the individual development of Ostrinia furnacalis, while the individuals of the Ostrinia furnacalis, which eat transgenic corn kernel, have a strong reproductivity. A dynamic investigation on the individual physicochemical property and population quantity of Sitophlus zeamais during storage shows:The imago of Sitophlus zeamais, which eat transgenic corn kernel, is heavier and reproductive more efficiently.