The relationship between leaf area and yield of the field bean with a statistical study of methods for determining leaf area

The data presented show that a close approximation exists between leaf areas measured with a planimeter and leaf areas estimated from the use of factors obtained from length and width measurements of the center leaflets. Total leaf area = .004517 LXW (of center leaflet) is the best equation of the four because of the time saved since only the length and width of the center leaflet are necessary. It would be possible to secure the leaf area of a bean plant without necessitating the removal of the leaves. The only measurements required would be the length and width measurements of the center leaflet. The data show that the measurements of 36 leaves are sufficient to arrive at a suitable factor. It seems possible that this method of securing leaf areas need not be limited to the bean plant but could be used with any plant with similar leaf habits providing a suitable factor were calculated. In all instances, plants both large and small, from fertilized plats, had a greater average leaf area than plants from untreated plats. However, these differences were not found to be significant except in one case in the large plants and one in the small plants, but since all of the differences were in favor of the fertilized plats the results indicate a tendency for plants from fertilized plats to have greater leaf area than plants from untreated plats. Similarly the yields of plants from the fertilized plats were greater than those from unfertilized plats with one exception, but again these differences were not great enough to be significant with the number of plants used. In either case the indications are that if a sufficient number of plants had been used significant differences might have resulted. With the inherent variability that is evident between individual plants the data bring out very clearly the necessity of using a number of plants sufficiently large to overcome this variability before a definite conclusion can be reached.