Manual emasculation and pollination methods for wheat and barley crossing

Author

James E. Lothrop

Date of Award

6-1980

Degree Type

Thesis

Degree Name

Master of Science

Major

Plant, Soil and Environmental Sciences

Major Professor

V.H. Reich

Committee Members

F.L. Allen, L.N. Skold

Abstract

A field study was conducted to evaluate the effect of several methods of emasculation and pollination on the efficiency of producing F₁ seed of barley (Hordeum vulgare L.) and wheat (Triticum aestivum L. em Then.). Winter barley cultivars 'Volbar' (female parent) and 'Harrison' (male parent) were used in this study. In wheat, the cultivars Arthur' (female parent) and 'Blueboy' (male parent) were chosen. Thirteen treatments were used in order to evaluate the effectiveness of some of the logical combinations of three methods of emasculation (clip, scissor, and pry or slit) and five methods of pollination (approach, anther, twirl, folded paper, and spatula). Control treatments consisting of emasculation without pollination tested the efficiency of the emasculation treatments in preventing selfing.

In the wheat study, it was found that all three methods of emasculation were effective, and that there were no significant differences (P ≤ .05) in the effectiveness of the methods. Selfing rates were 4.9%, 3.5%, and 0.0% for the clip, scissor, and pry methods. The highest percent seed set (68.3%) was achieved when wheat spikes were emasculated by the clip method and pollinated by the approach method. This treatment resulted in a percent seed set which was significantly higher (P ≤ .05) than that of all other treatments except for a treat ment with clip emasculation and folded paper pollination method, which gave the second highest percent seed set, 57.2%. Seed weight of the F₁ seed was significantly higher (P ≤ .05) when the pry method of emasculation was combined with the ripe anther and spatula methods of pollination. Scissor emasculated spikes produced the lightest seeds, while clip emasculated spikes produced seed of intermediate weight.

In the barley study, it was found that all three methods of emasculation were highly effective, and that there were no significant differences (P ≤ .05) in the effectiveness of the methods. Selfing rates were 0.48%, 0.26%, and 0.0% for the clip, scissor, and slit methods. Barley spikes which were emasculated using the slit method and pollinated using the ripe anther method had the highest percent seed set of all the treatments, 75.5%. However, this treatment was not significantly (P ≤ .05) higher in percent seed set than six of the other nine non-control treatments. Seed weight of the F₁ seed, which often affects germination and seedling vigor, was significantly higher when the slit method of emasculation and the ripe anther or spatula methods of pollination were used. Scissor emasculated spikes produced the lightest seeds, while clip emasculated spikes produced seed of intermediate weight regardless of method of pollination.

It was found in both the wheat and barley studies that some of the techniques involved were very laborious and time-consuming, while others were fast and easy. For wheat, greatest returns on time and labor were achieved when clip emasculated spikes were pollinated using the approach method. For barley, greatest returns on time and labor were achieved when scissor emasculation was combined with the approach or twirl methods of pollination.

Recommended Citation

Lothrop, James E., "Manual emasculation and pollination methods for wheat and barley crossing. " Master's Thesis, University of Tennessee, 1980.
https://trace.tennessee.edu/utk_gradthes/7752