Environmental effects on pollination and receptacle development in the strawberry

SummaryPollen formation and receptacle and achene development were studied in four varieties of strawberry growing in glasshouses and growth cabinets. Low temperatures and short days reduced pollen fertility but had only a small effect on percentage fertilization rates following the use of fertile pollen. Merton Princess and Redgauntlet were affected more adversely than other varieties by short days and low temperatures.Tests made with Redgauntlet at 10°, 12.5° and 15 °C in long and short days at two light intensity levels showed that temperature was the major environmental factor regulating pollen formation, achene fertilization and receptacle development. Receptacle size at. maturity tended to be inversely proportional to temperature, but the relationship was modified by other factors, such as the position of the receptacle on the flower truss, the level of fertilization achieved, interactions with light intensity and photoperiod, and the level of embryo abortion during achene development. Long days promoted rapid development of the receptacle and a short period from anthesis to maturity. Low light intensities restricted receptacle size by reducing both the mean daily incremental growth rate and the level of pollen formation.Correlations between achene number and receptacle size were sensitive to variations in the physical conditions of the environment, as well as to internal factors such as the position of the receptacle on the flower truss.