Effect of Source Size on Rice Pollen Diffusion under Field Experiments

doi:10.3969/j.issn.1000-6362.2018.12.004

Abstract

Abstract: Pollen-mediated gene flow from rice is one of the main ways of transgenic escape. Therefore, it is great significance to master the rule of pollen diffusion for the study of gene flow. In this study, three treatments with different source size of 5m×5m(TR1), 10m×10m(TR2) and 15m×15m(TR3) were designed. Rice panicles per unit area, flowering spikelets per panicle, pollen grains for each spikelet and pollen depositions along the main wind direction were observed to calculate pollen source strength per unit area and effective source strength ratio. The effect of source size on pollen source strength, pollen deposition, effective source strength ratio and pollen diffusion distance was studied. The results showed that: (1) source size did not affect the pollen source strength per unit area, while it could only change the total source strength. The proportion of total source strength between TR1, TR2 and TR3 was 1:4:9. (2) Source size did not change the characteristic of pollen deposition along the main wind direction. The pollen deposition first had a rapid increase and then declined after the peaks within the source area. In the downwind, pollen deposition could be expressed as the negative exponential function of distance. (3) The pollen source size was larger, the pollen deposition at different distances was greater, and the pollen diffusion distance was increased accordingly. However, this effect would levelled off with a larger pollen source size. (4) 27.9%?33.4% of the effective source strength ratio for three treatments meant that only about 30 percent pollen could escape and dropped down out of the source area, which might lead to gene flow. But, the effective source strength ratio would gradually decrease, when the pollen source size was increasing. (5) There were similar effects of wind on pollen diffusion between different treatments. The effective source strength ratio was larger and the pollen diffusion distance was farther at higher wind speed. Wind direction mainly affects the effective source strength ratio. It should be noted that the wind had a more significant influence on the larger pollen source.

Key words: Rice, Pollen source size, Pollen source strength, Pollen deposition, Effective source strength ratio

ZHANG Jie, WANG Yong-qun, HU Ning, JIANG Xiao-dong, LIU Zi-he, PEI Xin-wu. Effect of Source Size on Rice Pollen Diffusion under Field Experiments[J]. Chinese Journal of Agrometeorology, 2018, 39(12): 796-804.

References

[1] 单琨,刘布春,李茂松,等.基于花粉量的作物产量预测模型研究进展[J].中国农业气象,2010,31(2):282-287. Shan K,Liu B C,Li M S,et al.Research progress of pollen variable models for forecasting crop yield[J].Chinese Journal of Agrometeorology,2010,31(2):282-287.(in Chinese) [2] Dietiker D,Stamp P,Eugster W.Predicting seed admixture in maize combining flowering characteristics and a lagrangian stochastic dispersion model[J].Field Crops Research,2011, 121(2):256-267. [3] 裴新梧,袁潜华,胡凝,等.水稻转基因飘流[M].北京:科学出版社,2016. Pei X W,Yuan Q H,Hu N,et al.Rice transgene flow[M]. Beijing:Science Press,2016.(in Chinese) [4] 贾士荣,袁潜华,王丰,等.转基因水稻基因飘流研究十年回顾[J].中国农业科学,2014,47(1):1-10. Jia S R,Yuan Q H,Wang F,et al.What we have learnt in ten years’ study of rice transgene flow[J].Scientia Agricultural Sinica,2014,47(1):1-10.(in Chinese) [5] Jia S R,Yuan Q H,Pei X W,et al.Rice transgene flow:its patterns,model and risk management[J].Plant Biotechnology Journal,2015,12(9):1259-1270. [6] 樊龙江,吴月友,庞洪泉,等.转基因Bt水稻花粉在桑叶上的自然飘落浓度[J].生态学报,2003,23(4):826-833. Fan L J,Wu Y Y,Pang H Q,et al.Bt rice pollen distribution on mulberry leaves near rice fields[J].Acta Ecologica Sinica,2003,23(4):826-833.(in Chinese) [7] Wang L,Haccou P,Lu B R.High-resolution gene flow model for assessing environmental impacts of transgene escape based on biological parameters and wind speed[J].PLoS ONE,2016,11(3):1-16. [8] 胡凝,陈万隆,刘寿东,等.水稻花粉扩散的模拟研究[J].生态学报,2010,30(14):3665-3671. Hu N,Chen W L,Liu S D,et al.A model for simulating rice pollen dispersal[J].Acta Ecologica Sinica,2010,30(14): 3665- 3671.(in Chinese) [9] Kanya J I,Kinyamario J I,Amugune N O,et al.Dispersal distance of rice(Oryza sativa L.) pollen at the Tana River delta in the coast province,Kenya[J].African Journal of Biotechno- logy,2009,8(10):2265-2270. [10] Song Z P,Bao R L,Chen J K.Pollen flow of cultivated rice measured under experimental conditions[J].Biodiversity and Conservation,2004,13(3):579-590. [11] Rong J,Song Z,de Jong T J,et al.Modelling pollen-mediated gene flow in rice:risk assessment and management of transgene escape[J].Plant Biotechnology Journal,2010,8(4): 452-464. [12] 胡凝,曹明会,江晓东,等.不同品种水稻开花量估算模型[J].中国农业气象,2013,34(4):440-446. Hu N,Cao M H,Jiang X D,et al.Estimation model of flowering amount of different rice varieties[J].Chinese Jour- nal of Agrometeorology,2013,34(4):440-446.(in Chinese) [13] Marceau A,Loubet B,AndrieuB,et al.Modelling diurnal and seasonal patterns of maize pollen emission in relation to meteorological factors[J].Agricultural and Forest Meteorology, 2011,151(1):11-21. [14] 李如海,张忠旭.北方杂交粳稻保持系产粉量研究[J].杂交水稻,2017,32(2):27-29. Li R H,Zhang Z X.Study on the production of powder in the maintaining lines of northern Japonica hybrid rice[J].Hybrid Rice,2017,32(2):27-29.(in Chinese) [15] 张忠旭,李全英,张丽颖,等.北方杂交粳稻恢复系产粉量研究[J].杂交水稻,2010,(s1):492-494. Zhang Z X,Li Q Y,Zhang L Y,et al.Study on yield of restorer lines of Japonica hybrid rice in North China[J].Hybrid Rice,2010,(s1):492-494.(in Chinese) [16] Fonseca A E,Lizaso J I,Westgate M E,et al.Simulating potential kernel production in maize hybrid seed fields[J].Crop Science,2004,44(5):1696-1709. [17] 敖光明,王志兴,王旭静,等.主要农作物转基因飘流频率和距离的数据调研与分析Ⅳ:玉米[J].中国农业科技导报, 2011,13(6):27-32. Ao G M,Wang Z X,Wang X J,et al.Data survey and analysis of the transgene flow frequencies and distances in major crops Ⅳ:maize[J].Journal of Agricultural Science and Technology,2011,13(6):27-32.(in Chinese) [18] Luna V S,Figueroa M J,Baltazar M B,et al.Maize pollen longevity and distance isolation requirements for effective pollen control[J].Crop Science,2001,41:1551-1557. [19] Bannert M,Stamp P.Cross-pollination of maize at long dista- nce[J].European Journal of Agronomy,2007,27(1):44-51.