Pollen Distribution and the Seedset on Triticum aestivum L.1

Abstract
Wheat (Triticum aestivum L. em Thell.) pollen dispersion was estimated, utilizing the Kramer‐Collins spore trap and tape on glass rods, in Kansas during 1966, 1968, and 1969. Seedset and yield were recorded in 1966 and 1968 on cytoplasmic male‐sterile (cms) lines. The malesterile sources were cms ‘Bison,’ ‘Shawnee,’ ‘Parker,’ ‘Scout,’ and ‘Aztec,’ with Shawnee B‐line as the pollen source. The male‐sterile lines extended 60 m north to south and 48 m east to west in 1968 and 1969, and 60 m in four directions in 1966.Pollen distribution, measured continuously in the Kramer‐Collins spore trap, gave a diurnal pattern in 1966 but not in 1968. Cold, cloudy weather in 1968 resulted in a low but nearly continuous pattern throughout the pollinating period. Pollen grains, as measured by tape on glass rods, decreased in numbers as distance from the pollen source increased, but were recorded as far as 60 m from the source. Beyond 3 m, the amount of pollen decreased rapidly.Seedset and yield patterns were similar to that of pollen number; thus, pollen number and seedset correlated significantly.