Effects of Competition Among Flammulina Velutipes Fruitbodies on Their Growth

ABSTRACT

Flammulina velutipes was grown on nutrient-supplemented sawdust and specific numbers of the earliest and largest fruitbodies were left per culture. Ranked by decreasing length before they elongated rapidly they showed a corresponding gradation in final dimensions and fresh weights of stipes and pilei both in still air with KOH present and in flowing air. The fruitbodies were much heavier in flowing air, mainly because of the larger size of the pilei. Young fruitbodies of different ranks left alone on a mycelium attained larger dimensions than those of the same ranks in groups, and reached 60–80% of the total weights of groups of 3–7 fruitbodies each in still air, and 54–64% of the weight of five fruitbodies in flowing air. Fruitbodies of the same ranks weighed more in smaller than in larger groups but the total weights of groups of 3–7 fruitbodies each did not differ significantly. Competition was demonstrated also for fruitbodies in their late phase of rapid elongation. Pileus/stipe weight ratios increased with decreasing numbers of fruitbodies on a mycelium and were greater in flowing than in still air. The results indicate that fruitbodies in groups inhibit each other's growth by competing for materials supplied in limited amounts from the mycelium and distributed among individuals proportionately to their ranks. Factors which limit the availability of substrates to the fruitbodies are discussed.

Key Words:

• competition
• growth
• fruitbodies
• Flammulina velutipes