Plant Mixtures Have Higher Yields than Monocultures
A new study published in the journal Nature finds that growing grasses in a complementary mixture can have higher yields than growing in a monoculture – growing only a single cultivar.
Debra Zuppinger-Dingley and her co-authors compared the performance of grasses in monoculture to grasses taken from a monoculture but planted in a mixture, and also to grasses taken from a mixed environment and planted in a mixture.
They found that the mixtures performed better, especially when the grasses were taken from a mixed environment.
The results suggest that crops may perform better if they are adapted to mixed planting, in a process the researchers call “character displacement.”
The idea is that different crops planted together will have different nutrient needs, different water needs, and will also have different pests. Essentially they will fill different niches within the same field, and will therefore make more efficient use of fertilizer, water, and sunlight.
Further, monocultures are known to attract pests. A mixed planting reduces pests by plants partially shielding each other from their pests.
Currently, however, many cultivars have been bred and optimized for monoculture. If, rather, we breed and select plants for grown in mixture they will evolve traits that better complement each other.
“Grasses, for instance, develop thicker leaves, which are able to utilize the direct sunlight in the upper layer of a meadow while clover species sprout larger but thinner leaves to absorb the weaker light close to the ground more effectively.”
The research suggests that cultivating crops specifically for use in diverse plantings can have multiple advantages.