Table 1 List of eight studied traits and their abbreviations

Number of Spikes Per Plant

(number)

NSPP

Total numbers of normal spikes were counted from five plants of each plot.

Spike Length (cm)

SL

It measured from the base of the spike to the tip, excluding awns (only main tillers were used and five values per plots averaged to obtain the SL values).

Number of Spikelets Per Spike (number)

NSPS

A total of five random spikes from plants selected for NSPP were used for this measurement, spikelet number was counted from the basal sterile spikelet to the top fertile spikelet.

Grain Weight Per Spike

(gm)

GWPS

After thrashing and cleaning of five spikes, the grain weight was calculated which was based on the mean of five spike per plot.

Lowest Tiller Height

(cm)

LTH

Measured from the ground level to the tip of the spike and excluding awns.

Spike Layer Thickness

(cm)

SLT

It measured how the spikes are distributed in a plant and measured the dispersion of the inter-tiller height. Measured as PH-LTH + SL.

Spike Layer Number (number)

SLN

Ratio of SLT and SL (SLT/SL).

Spike Layer Uniformity

(ratio)

SLU

It measures the uniformity of the spikes of the inter-tiller of a genotype or the consistency of the spike distribution in the vertical space and calculated as SLU=SL/SLT. A value of 1 indicates that all the inter-tiller spike heights are identical. However, lower values indicate the uneven heights of the measured spikes of the genotype.