Genetic analysis on plant type traits and yield traits in tartary buckwheat hybrid progeny

【Objective】 The study aimed to conduct a genetic analysis of plant type traits and yield traits in tartary buckwheat hybrid progeny，providing theoretical basis for the cultivation of new dwarf tartary buckwheat varieties. 【Method】 The study focused on the F₂ and F₃ generation populations of hybrid progeny from 2 tartary buckwheat varieties with great differences in plant height. The genetic patterns of 8 agronomic traits were analyzed，including plant height， node number of main stem，number of first branches，number of secondary branches，stem diameter，number of seeds per plant，seed weight per plant，and thousand-kernel weight，along with the analysis of the correlation among these traits. 【Result】 The 8 agronomic traits exhibited superparental segregation in both F₂ and F₃ populations. The coefficients of variation for node number of main stem and thousand-kernel weight were less than 20.00%，while the coefficients for the number of seeds per plant and seed weight per plant were greater than 50.00%. The coefficients for all other traits ranged from 20.00% to 40.00%. The additive variance for plant height，node number of main stem，number of seeds per plant and seed weight per plant was less than the dominant variance，with a mean degree of dominance greater than 1.00. Conversely，for the number of first branches，number of second branches，stem diameter and thousand-kernel weight， the dominant variance was less than the additive variance，resulting in a mean degree of dominance less than 1.00. In this case，the narrow sense heritability，broad sense heritability and fixed heritability of thousand-kernel weight were greater than those of the other traits. Correlation analysis among agronomic traits in the F₃ generation population revealed that both plant height and seed weight per plant were extremely significantly and positively correlated with number of seeds per plant，thousand-kernel weight，node number of main stem，number of first branches，number of secondary branches and stem diameter（P<0.01，P<0.001）. A total of 13 superior lines were identified which were shorter than the female parent and had a greater number of seeds per plant and seed weight per plant than the female parent，with 3 lines being at least 50 cm shorter than the female parent. Correlation analysis among the agronomic traits of the 13 superior lines revealed extremely significant positive correlation between plant height and the node number of main stem（P<0.01），and extremely significant positive correlation between seed weight per plant and both stem diameter and number of seeds per plant（P<0.001）. Both plant height and seed weight per plant were not significantly correlated with the other traits（P0.05）. 【Conclusion】 In the breeding process for high-yield dwarf tartary buckwheat，thousand-kernel weight has a low correlation coefficient with other traits and exhibits high heritability，allowing for single-plant selection in the early generations of hybridization. However，since plant height shows significant or extremely significant positive correlation with other main agronomic traits，it is necessary to comprehensively consider the correlations among traits during single-plant selection to achieve the optimal selection target for high-yield dwarf tartary buckwheat.