Quantitative Analysis of Growth and Production of Two Local and Commercial Cultivars of Radish (Rhaphanus sativus L.) in Response to Different Levels of Planting Density

In order to compare the growth indices and phenological stages of development of two local and commercial varieties of radish in response to different levels of population, an experiment was conducted as factorial on the basis of completely randomized block design in the greenhouse in Ferdowsi University of Mashhad, Iran during 2009-2010. Treatments were included two varieties of radish as first factor and three levels of population containing 85, 120 and 170 Pl m-2 as second factor. Phenological stages and growth indices including fresh and dry weight, leaf area, relative growth rate, special leaf area, leaf area ratio, net assimilation rate, edible part yield and dry matter allocation to leaves and roots in optimal conditions since the beginning of germination until final harvest were analyzed. The results showed that there is no significant difference between two varieties in relation to the germination time and 2 and 4 leaves stages in different planting densities. But two varieties responded differently to the different planting densities since the beginning of tubering. The local variety showed higher leaf area ratio and leaf area index, and higher intercepted radiation, but the allocation of photosynthate was more to leaves than edible root. Commercial cultivar showed significantly more economic yield than local cultivar. Increasing the population to170 pl m-2 significantly increased leaf area and leaf area index, radiation use efficiency, leaf weight and biomass, but it had no significant effect on the radish root weight.