How to feed a hungry world

With the world's population expected to grow from 6.8 billion today to 9.1 billion by 2050, a certain Malthusian alarmism has set in: how will all these extra mouths be fed? The world's population more than doubled from 3 billion between 1961 and 2007, yet agricultural output kept pace — and current projections suggest it will continue to do so. Producing enough food for the world's population in 2050 will require a wholesale realignment of priorities in agricultural research. There is an urgent need for new seed varieties that offer higher yields but use less water, fertilizers or other inputs and are more resistant to drought, heat and pests. Equally crucial is lower-tech research into basics such as crop rotation, soil management and curbing waste – between one-quarter
and one-third of the food produced worldwide is lost or spoiled.

(Adaptado de Nature, n. 466, p. 531–532, jul. 2010.)

a) No período de 1961 a 2007, qual foi, segundo o texto, a relação entre o crescimento da população e a produção agrícola?

b) Além de investigações sobre novas variedades de sementes, que outras pesquisas seriam necessárias, segundo o texto, para garantir uma produção suficiente de alimentos em 2050?