Bøger af D. Vaughan

It has long been recognized that soil organic matter is the key to soil fertility. But it has another property, the nature and extent of which have been the subject of argu ment and controversy ever since scientists began to study the soil, and that is its ability to affect growth directly, other than by providing nutrient elements.

The Asian beans and grams, the species of Vigna (subgenus Ceratotropis), include several legumes that are an essential component in the diets of a large proportion of Asia's population, and interest in these legumes is growing as ethnic cuisine spreads worldwide.