Light
Effects of light on tomato growth are illustrated in figs 6.1,6.3 and 6.7 and are also discussed in greater detail in this chapter in the section above on vegetative growth. Light quality and photoperiod are not as important to tomato growth as the daily irradiation integral (Picken et al.,1986). Using only fluorescent light,however,decreases net assimilation rate by 20% relative to the same irradiance with incandescent lights added as a source of farred (Hurd,1974). Kronenberg and van de Hulst (1984) analysed the factors accounting for variation in the yields of early tomatoes in Dutch glasshouses. For the period 1970-80,62-74% of the fluctuation in crop yield could be attributed to differences in average hours of sunlight received by the crop.