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Hybrid rice development is stalled: how can it be saved?
Data show that in recent years the downward trend in hybrid rice varieties has been very pronounced. The number of varieties with an annual promotion area of more than 1 million mu rose from 46 in 2002 to a peak of 59 in 2004, then declined year by year to 29 in 2012; the number of varieties with an annual promotion area of more than 5 million mu fell from about 9 in the early period to 1 per year at present; since 2007, no variety with more than 10 million mu has appeared. The average annual promotion area of a single main hybrid rice variety fell sharply from 2.133 million mu in 1993 to 374,000 mu in 2012, a drop of 82.5%.