DOI: 10.5061/dryad.d7wm37qbx
title: Wild relatives to improve heat tolerance of cultivated quinoa (Chenopodium quinoa Willd.)

description: Quinoa (Chenopodium quinoa Willd., 2n = 4x = 36, AABB genome) is
 well-known for its high nutritional value and adaptability to marginal
 environments, but it is still mainly cultivated in relatively cool areas
 due to sensitivity to extended periods of high temperatures, particularly
 during the reproductive stages. The two AABB tetraploid wild relatives of
 cultivated quinoa, C. berlandieri and C. hircinum, can be found growing in
 hot lowland environments of North and South America, respectively, and may
 serve as a source of heat tolerance for introgression into cultivated
 quinoa. In our work, wild C. berlandieri showed the best yield performance
 under field heat conditions in late planting, followed by lowland quinoa,
 C. hircinum, and highland quinoa. The yield advantage of C. berlandieri at
 high temperatures was achieved by plants being able to maintain grain
 number at high temperatures better than the other genotypes. Further
 comparison between seed setting and pollen viability found positive trends
 between them under heat stress in cultivated quinoa, indicating limiting
 effects of pollen viability on grain setting. Therefore, we examined the
 effects of heat on pollen development and viability. Five representative
 accessions (C. berlandieri, C. hircinum Argentina, C. hircinum Chile, C.
 quinoa lowland, C. quinoa highland) were studied in detail with an
 environmentally-controlled heat treatment (five days at 38/33oC,
 day/night). Detrimental effects of heat on pollen viability in C. quinoa
 were observed, with an 80% reduction in the highland ecotype, whereas
 wild C. berlandieri had only a 30% reduction. The most heat-sensitive
 period, with respect to pollen viability, was 8 to 10 days before
 flowering, which we found corresponded to the early pollen mother cell
 stage of development. The period of highest sensitivity of pollen to heat
 was conserved among different Chenopodium species. At the end, in vitro
 heat treatments on pollen germination also demonstrated a comprehensive
 advantage of C. berlandieri over other accessions. This research suggests
 that wild relatives of quinoa, in particular C. berlandieri, could be
 crossed with cultivated quinoa to introduce reproductive heat tolerance.
description: # Wild relatives to improve heat tolerance of cultivated quinoa
 (*Chenopodium quinoa* Willd.) Dataset DOI:
 [10.5061/dryad.d7wm37qbx](10.5061/dryad.d7wm37qbx) ## Description of the
 data and file structure This is our data generated for our manuscript. ###
 Files and variables #### File: FieldData.xlsx **Description:**  This Excel
 file has three sheets. Please note: empty cells in these files mean data
 were not available due to an unexpected reason (like dead plants,
 therefore no sample for analysis, or other logistic issues)
 1."FieldRawData", all the raw data collected;
 2."FieldP3vP1", data of planting date 3 (P3) relevant to P1 from
 field experiment; 3."FieldEmmeans", estimated means for all
 traits from the field experiment; ##### Variables for
 "FieldRawData" * Block: block# of experiment design * Plot:
 plot# * SubPlot: subplot with three planting dates * Gcode: genotype code
 * Genotype: genotype name * Group: grouping of genotypes * Pdate: planting
 date * Unique code: code combines genotype_block_planting date * Yield:
 yield per plant (g) * GN: grain number per plant (#) * TKW: thousand grain
 weight(g) * PH: plant height (cm) * DTF: days to flowering (# of days) *
 DTM: days to maturation (# of days) * RGF: duration from flowering to
 maturation (# of days) * GDDfl: thermal sum from sowing to flowering (°Cd)
 * GDDrgf: thermal sum from flowering to maturation (°Cd) * SC: stomatal
 conductance (mmol m−2 s−1) * PT: panicle temperature (°C) * LT: leaf
 temperature (°C) * SPAD1-6: chlorophyll index at SPAD with 6 timepoints
 (chlorophyll index unit) ##### Variables for "FieldP3vP1" *
 Group: grouping of genotypes; * P3/P1_GY: P3 relevant to P1 of grain yield
 (%) * P3/P1_TKW: P3 relevant to P1 of thousand grain weight (%) *
 P3/P1_GN: P3 relevant to P1 of grain number (%) ##### Variables for
 "FieldEmmeans" * Genotype: genotype name * Group: grouping of
 genotypes * Pdate: planting date * Genotype_Pdate: combination of Genotype
 and Pdate * Yield: yield per plant (g) * GN: grain number per plant (#) *
 TKW: thousand grain weight(g) * PH: plant height (cm) * DTF: days to
 flowering (# of days) * DTM: days to maturation (# of days) * RGF:
 duration from flowering to maturation (# of days) * GDDfl: thermal sum
 from sowing to flowering (°Cd) * GDDrgf: thermal sum from flowering to
 maturation (°Cd) * SC: stomatal conductance (mmol m−2 s−1) * PT: panicle
 temperature (°C) * LT: leaf temperature (°C) * SPADt50: the day of 50%
 reduction (# days after flowering) #### File: PV and SS.xlsx
 **Description:**  The data in "PV and SS" were from a growth
 chamber experiment. It contains 11 sheets in total, with sheets 1-5 for
 pollen viability data and 6-10 for seed setting, and the last sheet for
 combined pollen viability and seed setting. Both pollen viability and seed
 setting were expressed as a percentage. Please note: empty cells in this
 file mean measurements were not available due to plants have a limited
 flowering period. **Variables for sheet 1-10:** * Geno: genotype * Exp:
 experiment * Trt: treatment, either control or heat * Rep: replication *
 Code: combine genotype_trt * S-16 to S-0: developmental stage at heat
 stress initiation, expressed days before flowering **Variables for sheet
 11 PVvSS:** * Genotype: genotype * Trt: treatment, either control or heat
 * PV: pollen viability (%) * SS: seed setting (%) #### File: PGPTdata.xlsx
 **Description:**  The data in this file is from *in vitro* pollen
 germination analysis. Please note: empty cells in this file mean
 measurements were not available. **Variables for sheet
 "PGdata"** * Genotype: genotype * Group: grouping of genotypes *
 Temperature: incubation temperature during pollen germination (°C) * PV:
 pollen viability in percentage (%) **Variables for sheet
 "PTdata"** * Genotype: genotype * Temperature: temperature of
 either 34 or 38 (°C) * Time: time in hours since incubation (h) *
 Timepoint: timepoints from 1-3 for measurements * PTL: pollen tube length
 in micrometers (µm) **Access information** NA