玉米专题1一中国玉米生产基本情况4, v3.ppt

Corn pruduction in Huanghuaihai Plain Two crops (wheat-corn) a year Account for 35％ of total corn area，37％ of total production Yield constraints：drought and short growing season, low fertilizer use efficiency Huanghuaihai Direct corn planting without till after wheat Rotary till of corn stover prior to wheat sowing ′ y = -0.0725x + 3.48 R 2 = 0.359**(n=27, 2008) y = -0.0567x + 2.9765 R 2 = 0.157*(n=24, 2007) 0 1 2 3 30 35 40 45 50 2007 年 2008 年 Delayed corn harvest until maturity Kernel milk line day after silking Gain in 1000-grain weight (g/day) delay from Sept 15-25 to Oct 1-10 in summer corn region Corn in Southwest of China Multiple cropping Hilly fields Account for 14％ of total corn area，11％ of total production in China Yield constraints： seasonal drought extended rainy days Southwest Multiple cropping, inter-cropping Rain water collection for drought,ridge planting for flooding Corn transplanting Plastic film mulching Corn stover staying in fields Rice straw mulching for growing potato, rape and wheat Irrigated corn in Northwest of China One crop a year in most areas Account for 2％ of the total corn area，3％ of total production in China Annual rainfall: 71-144 mm South Northwest Film mulching Drip irrigation Mechanized, direct grain harvest Corn production in South of China Long growing season for corn growth (220～360 days) High annual rainfall (mean 1421 mm) Winter corn Multiple cropping Account for 4％ of total corn area，4％ of total production in China South Seedling and transplanting Greenhouse, arched shed, and flastic muchling （X P Chen et al，2011） Projected corn demand in China Requested corn yield: 6.6 – 7.8 t/ha (105 – 124 bu/acre) 1. Expanding corn area by using shorter maturity varieties Using RM 72-113 day hybrid could add 3.8 million acres in northeast (upper) and 2.7 million acres in northwest (lower) of China. Paths to increase corn pruduction in future 2. Expanding corn area by mechanized operation and replacing other