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Incomplete diallel cross, general diallel cross, fixed model diallel cross, North Carolina II design SUMMARY In this and in an earlier paper formulas are given for analysing genetic variation in general (connected) diallel cross designs, including incomplete and unbalanced designs. Also North Carolina II (NC II) designs are considered.In this paper the procedures are illustrated by the example of an irregular incomplete diallel cross.

Growth curves, measuring growth (design), multivariate analysis of variance (MANOVA), SUMMARY In the first part of this paper some experimental conditions necessary for a valid statistical analysis of differences in growth curves are discussed .Next the multivariate character of growth curves is considered . Data on the growth curves of three genotypes of an experiment with tomatoes of the IVT are used for illustrating the computational procedure and some aspects of interpretation .The growth curves of log dry leaf weight for each plot could be described by a quadratic function of time and were characterised by three components : mean level m, slope 1(linear component) and curvature q (quadratic component) .Univariate analyses of variance (ANOVA) showed significant differences between cultivars for each growth component ; however, this is only part of the information as the correlation between the components is not involved. From a multivariate analysis of variance (MANOVA) it appeared that in this experiment the differences in growth between the cultivars were best expressed by using mean level m only .An estimate of the final (reduced) statistical model underlying the tomato example is derived . It is advised to split up growth into different phases of development each with its own analysis . At least four harvest dates for every phase seem desirable.

Different testing methods to measure solidity and dry matter content of onion bulbs were examined. The correlation coefficients between the characters determined were calculated. No strong correlations were found between the results of the different methods of measuring solidity. The refraction value of the press juice gives reliable information on the dry matter content of the onion bulb.