GrainGenes
A Database for Triticeae and Avena
Nikitenko et al., pp. 53-55
II. 25. Genetical analysis of diallel crosses for the trait of protein in spring barley.
G. F. Nikitenko. Scientific Agricultural Research Institute in the Central Regions of the Non-Chernozem, 143013, Mbscow-Nenchinovka, USSR, and M. A. Polukhin and V. A. Gorshkova, Scientific Research Agricultural Institute in the Central Chernozem Zone, 397463, The Voronezh Region, The Talov District, USSR.
The aim of the present investigation was to establish a genetical system controlling the protein inheritance in the grain of five spring barley varieties, which varied considerably in this trait. (G. F. Nikitenko, M. A. Polukhin, 1973). The analyses were carried out by the methods of Hayman (1954) and Jinks (1954) modified by Mather and Jinks (1971). Protein content in F1 and F2 was subjected to the statistic treatment as follows: the variance analysis is of genetical variation parents; the covariance (W2) minus uniformity variance (V2); the covariance regression (W2) for variance (V2); correlation coefficient (Rx/W2 + V2] among the protein average content in the grain of parent forms and the sum of covariance as a measure of dominance to detect the positive and/or negative accumulative effect of dominant or recessive alleles; assessment of the inheritance stipulated by the additive action of genes.
The analysis of the results of our diallel crossings has shown that the additive action of genes played a prevailing role in the genetical control of protein content, though a dominant effect is also significant (Table 1).
According to the method of Hayman, the analysis of regression is possible at the ununiform difference between the covariance and the variance (W2 - V2]. In our experiment, the data (W2 - V2] present comparatively small and similar values: the uniformity of this difference is proved by the Amsela test (t1=0,669: t2=131 atp=3). Consequently, the regression W2 on V2 may be presented.
The results of the regression analysis showed that no significant differences were detected between F1 and F2. (Fig. 1). The regression line is crossing the axis of the covariance (W2) practically at its very beginning and distribution of dates, indicating the distribution of dominant and recessive genes among the parents were near the line (bW2/V2 = 0.848, bW2/V2 = 1.089). According to Hayman, the parent forms containing the most of dominant alleles are situated near the crossing point (at the bottom of the regression line). In our case, these were the varieties with a low or average content of the grain protein (Moskovsky 121 and Nutans 187); varieties with a high content of protein were distributed at some distance from the beginning of the regression line - the varieties Eurepean 353/133 and Spartan II.
Regression W2 + V2 which gives the line, near to the line of a single incline, indicates the absence of epistatic effect and/or randomized distribution of genes. The elicit positive or negative effects of accumulation of dominant or recessive genes was a correlation between middle values of parents with W2 + V2, which indicates the high level of this relation was calculated. For F1 and F2, correlation coefficients were, respectively, +0.854 and +0.931. Thus, a low content of protein was provided by accumulation of dominant alleles and a high one, on the contrary, by recessive alleles.
Parameter, expressed as h2 in percentage, is equal in F1 to 55%, in F2 to 50%, which indicates a high inheritance of the trait in the given system and testifies to the prospects of selection for the high content of the grain protein using the studied varieties as parent forms in the course of hybridization.
References:
Nikitenko, G. F. 1973. On the spring barley selection for the grain
quality. "Selection and seed production", No. 2:34-35. In Russian.
Hayman, B. I. 1954. The analysis of variance of diallel crosses. Biometrics, 10:234-244.
Jinks, S. L. 1954. The analysis of continuous variation in a diallel cross of Nicotiana rustica varieties. Genetics, 39:767-788.
Mather, K., and S. L. Jinks. 1971. Biometrical genetics. London.