INHERITANCE STUDIES OF SEVERAL QUALITATIVE AND QUANTITATIVE CHARACTERS IN SPRING WHEAT CROSSES BETWEEN VARIETIES RELATIVELY SUSCEPTIBLE AND RESISTANT TO DROUGHT

Abstract

Genetic studies were made in the F2 and F3 generations of the crosses, Selection I-28-60 × Milturum, Reward × Caesium, and Caesium × Marquis. It was found that the character glume color was controlled by either one or two factor pairs in the cross Selection I-28-60 × Milturum, and by two factor pairs in the crosses Reward × Caesium and Caesium × Marquis. The characters, awning, straw color, glume pubescence and spike regularity were each governed by one factor pair, while three factor pairs were operative in the inheritance of seed color.Polymeric factors apparently control the inheritance of the quantitative characters straw strength, plant height, earliness and grain yield. A partial dominance of strong straw and earliness was found in the crosses Reward × Caesium and Caesium × Marquis. Tallness and low grain yield were partially dominant in the cross Reward × Caesium. Evidence for transgressive segregation of earliness was obtained in the cross between Caesium and Marquis.The characters glume color, awning, straw color, glume pubescence and spike regularity were inherited independently. White straw color and earliness were definitely associated in the crosses Reward × Caesium and Caesium × Marquis. The characters straw color and plant height were loosely linked in the Caesium × Marquis cross. Grain yield was not significantly correlated with straw strength, plant height or earliness in the cross between Reward and Caesium. Small but significant relationships were found among the characters straw strength, plant height and earliness in the crosses Reward × Caesium and Caesium × Marquis. The relation between heading and maturity was studied only in the F4 of Reward × Caesium, in which case a strong positive correlation was obtained.