PANICLE DEVELOPMENT AND PLANT VIGOUR IN DACTYLIS GLOMERATA L. IN RELATION TO DATE OF SOWING AND PLANTING

Abstract

Cocksfoot sown late in summer or early in autumn to provide a seed crop the following year generally produces a disappointing yield. The experiments described were set up to study this problem. Seeds of four varieties, American, Danish and two British cocksfoots, were sown at fortnightly intervals during the spring and summer of 1956. The sowings were repeated in 1957 with the addition of Potomac, a bred variety from USA, and an ecotype from Israel.Plants sown after mid‐May showed a diminishing capacity to produce panicles the following summer. The last sowing in 1957 caused the weight of green hay per plant in 1958 to be at least 50% below that of the spring‐sown plants, and panicle number to drop 60–80%. Sowing after mid‐May affected panicle development in the autumn and in the following hay crop. Date of sowing had no effect on mean date of panicle emergence in the following summer. In the populations as a whole, neither the presence nor the number of panicles in the first autumn was related to productivity in the hay stand.