DOI: 10.5061/dryad.k6djh9wjv
title: Evaluating bread wheat varietal responses to late-spring frost conditions

description: This study investigates the impact of late-spring Frost (LSF) stress on
 wheat (Triticum aestivum) during critical reproductive stages. A factorial
 experiment was conducted with three wheat genotypes ('Roshan',
 'Falat', and 'Superhead'), three growth stages (pollen
 development, spike emergence, and pollination), and three stress levels
 (normal, one-day stress, and four-day stress) in a completely randomized
 design with nine replications. Analysis of variance and mean comparison
 (LSD method) showed that wheat varieties responded differently to growth
 stages and stress durations, with 'Roshan' being more sensitive
 and 'Superhead' more adaptable. Proline accumulation and
 increased photosynthetic pigment levels were identified as stress
 resistance mechanisms, though they did not fully prevent yield reductions.
 Principal Component Analysis (PCA) explained 75.42% of the variation,
 showing negative correlations between yield-related traits (grain number
 and grain weight) and the first component, while chlorophylls,
 carotenoids, and proline correlated positively. These results emphasize
 the importance of understanding varietal differences in LSF tolerance and
 the need for phenotyping and genetic improvements to develop cold-tolerant
 wheat varieties. The findings highlight the vulnerability of reproductive
 stages and the importance of targeted breeding strategies to enhance crop
 resilience and ensure yield stability in climates affected by LSFs.
description: # Data on the Impact of Late-Spring Frost Stress on Wheat Reproductive
 Traits \[Access this dataset on Dryad](Dataset DOI link) This dataset
 originates from a factorial experiment assessing the impact of late-spring
 frost (LSF) stress on reproductive traits in wheat (*Triticum aestivum*).
 The experiment investigated physiological and yield-related responses in
 three wheat genotypes—'Roshan', 'Falat', and
 'Superhead'—when subjected to LSF during three critical growth
 stages: pollen development, spike emergence, and pollination. Frost stress
 was applied at two intensities: one-day LSF and four-day LSF, alongside a
 no-stress control group. A completely randomized design (CRD) was used
 with nine replicates per treatment. The resulting data provide insights
 into how reproductive-stage frost affects key physiological traits and
 yield components. ## Description of the data and file structure The
 dataset comprises mean values calculated from nine replicates for each
 treatment group (genotype × stage × frost level). Seven traits were
 measured: 1. Grain weight per main spike (g) 2. Number of grains per main
 spike 3. Chlorophyll a (mg/g) 4. Chlorophyll b (mg/g) 5. Total chlorophyll
 (mg/g) 6. Carotenoid (mg/g) 7. Proline (nmol/mg) Each physiological trait
 was assessed using standard field and laboratory protocols. The
 chlorophyll and carotenoid concentrations are expressed in milligrams per
 gram fresh weight (mg/g FW), while grain-related traits are in grams per
 spike and number per spike. There are no missing data codes used in this
 summary dataset. Additional raw replicate-level data may be available upon
 request. ## Code/Software No code is included with this dataset. However,
 standard data processing and statistical analysis were conducted using
 common packages in R and Excel. Users wishing to replicate the analyses
 should contact the corresponding author for details on analysis pipelines
 and raw data access.