Data from: Plant strategies for maximizing growth during drought and drought recovery in Solanum melongena L. (eggplant)

Data usage: This data represents the collection of physiological and biometric data of above- and below-ground plant traits in four species of Solanum melongena of Philippine origin (PHL 4841, PHL 2778, PHL 2789, and Mara). Half of the plants were subjected to significant water deficit, and half again of those deficit plants were allowed to recover after subsequent watering. This data is suitable to serve as a benchmark for trait values in S. melongena, as well as in studies of trait responses to terminal drought and episodic drought in agricultural settings. Traits in this dataset include Leaf Water Potential, total leaf area (cm2), Leaf Canopy temp, Fv/Fm, Photosynthesis, Stomatal Conductance, Transpiration Rate, Water Use Efficiency, Green Leaf Dry Weight, Senesced Leaf Dry Weight, Stem Dry Weight, Total Shoot Dry Weight, Leaf Area Ratio, Specific Leaf Area, Specific Leaf Weight, Basal Fine Root Mass, Total Fine Root Mass, Coarse Roots Mass, Total Root Mass, Root:Shoot Ratio, Total Fine Root length (cm), Total Fine Root Surface Area (m2), Total Fine Root Volume (m3), Specific fine root length (m/g), Root tissue density (g/m3), Fine root length:Leaf area Ratio (cm/çm2), and root mass fraction.
Methods and materials:
A greenhouse experiment was set up to identify physiological traits associated with drought tolerance in eggplant. Solanum melongena genotypes PHL 4841, PHL 2778 and PHL 2789 were chosen based on drought performance in previous field and greenhouse trials (58) of 100 germplasm accessions from the National Plant Genetic Resources Laboratory in the Institute of Plant Breeding, University of the Philippines at Los Baños, Laguna, Philippines. S. melongena ‘Mara’, a released variety from the Institute of Plant Breeding, UP Los Baños was included as a reference variety. Seeds were sown into seedling trays containing fritted clay (Turface Greens Grade, Profile Products, Buffalo Grove, IL, USA) at the end of February in a greenhouse in Fort Collins, CO. After 17-21 days seedlings were transplanted into 7.57 L plastic pots containing 10 kg fritted clay and watered to holding capacity via a drip irrigation before treatments were established. Pots were positioned on two greenhouse benches in a randomized complete block design of two factors: water availability (drought vs. well-watered control) and genotype (four genotypes). There were 5 replicates of each block (40 plants). This basic block design was doubled, and plants were harvested at 2 time points (post-drought and post-recovery) for a total of 80 plants.
Plants were maintained under a combination of natural sunlight and supplemental LED illumination on a 14:10 hour day:night cycle, corresponding to average temperatures of 22 and 29˚C. Plants were fertigated using Grow More water soluble fertilizer (Grow More, Inc., Gardena, CA) amended with additional N in the form of urea and additional K in the form of KH2PO4 to achieve 79.5-22.5-5 ppm N:P:K daily for the first month after transplantation and transitioned to 60-30-120 ppm N:P:K for the remainder of the experiment.
Drought treatments began at 5 weeks after transplanting and lasted for 2 weeks for all blocks (80 plants). “Drought” plants received 30% of evapotranspiration (ET) of “control” plants daily for the first week, and 10% daily in the second week. “Control” plants were given 100% of ET daily. ET was calculated by weighing control pots daily at 1400 hr to measure evaporative and transpiration water loss relative to 100% holding capacity. After the conclusion of the drought treatment, all remaining plants were re-watered to pot holding capacity.
Physiological measurements
Randomized measurements of drought and control plants were carried out from the 11th through the 15th and final day of the drought treatment on 50% of the experimental plant population. On each day, the third fully expanded leaf of each plant was measured for chlorophyll fluorescence (Fv/Fm) from 07:30 until 08:30 using a portable OS5P fluorometer (Opti-Sciences Inc., NH, USA). Each leaf was dark acclimated with leaf clips for 20 minutes prior to measurement. From 09:00 to 12:00 hrs, the same leaves were measured for photosynthetic rate, stomatal conductance, and transpiration using the Li-COR 6400XT infrared gas analyzer with attached leaf measurement chamber (LiCOR Inc., Lincoln, Nebraska). Conditions in the leaf measurement chamber were the following: PAR (photosynthetically active radiation) of 1800 µmol m-2s-1, leaf temperature of 25˚C, and CO2 concentration of 400 µmol mol-1. Instantaneous water use efficiency (WUEi) was calculated as the ratio of photosynthesis (An) to stomatal conductance (gs).
Leaf water potential (ΨL) was determined with use of a Scholander pressure chamber (Soil Moisture Equipment Corp., Santa Barbara, CA, USA). The same leaf used for gas exchange measurements was cut from each plant and immediately placed in a plastic bag in a cooler until ΨL could be measured (up to 1 hour).
After one week under full watering, “recovered” and control plants were again measured as above for chlorophyll fluorescence and leaf water potential.
Plant growth measurements
Following physiological measurements, the aboveground portions of drought and control plants were cut and partitioned into leaves and stem. Total leaf area was measured for each plant using a Li-3100C leaf area meter (LiCOR Inc., USA). Partitioned shoot tissue was then oven dried at 60˚C for 48 hours and weighed.
The belowground biomass of each plant was washed free of fritted clay and partitioned into fine and coarse roots. A representative sample of fine roots was obtained for each sample and stored in 30% ethyl alcohol for root scanning. Preserved fine roots were scanned in water in 2-D transparency mode with a desktop scanner (EpsonV750, Epson America Inc., USA) and analyzed using WinRHIZOTM software (Regent Instruments Inc., Canada). Remaining fine and coarse roots were dried and weighed as above. Leaf area ratio (total leaf area per total plant dry mass, m2 g-1; LAR) and specific leaf area (leaf area per leaf dry mass, m2 g-1; SLA), and leaf mass area (leaf dry mass per leaf area, g m-2; LMA) were calculated using the leaf data for each plant. Specific root length of fine roots (root length per dry mass, m g-1; SRLFineRts) and total root mass fraction (RMF, total root mass per total plant weight) were calculated using the fine root length and root biomass data from each plant (31,59)
At the end of the recovery phase, all plants were also destructively sampled for measurement of leaf area and above- and below-ground biomass partitioning as above.
Resources in this dataset:Resource Title: Data from: "Plant strategies for maximizing growth during drought and drought recovery in Solanum melongena L. (eggplant)". File Name: full_dataset.csv

数据应用：本数据集涵盖了菲律宾原产（PHL 4841、PHL 2778、PHL 2789和Mara）四个品种的茄子地上及地下植物性状的生理和生物测量数据。其中一半植株遭受了显著的水分亏缺，而在后续浇水后，再次有一半的水分亏缺植株得以恢复。该数据集可作为茄子（S. melongena）性状值的标准，并在研究作物环境中性状对终端干旱和间歇性干旱响应的学术研究中提供参考。数据集中的性状包括叶水势、总叶面积（平方厘米）、叶冠温度、Fv/Fm、光合作用、气孔导度、蒸腾速率、水分利用效率、绿色叶片干重、衰老叶片干重、茎干重、总茎干重、叶面积比、比叶面积、比叶重、基础细根质量、总细根质量、粗根质量、总根质量、根冠比、总细根长度（厘米）、总细根表面积（平方米）、总细根体积（立方米）、特定细根长度（米/克）、根组织密度（克/立方米）、细根长度与叶面积比（厘米/平方厘米）、以及根质量分数。

研究方法与材料：为确定与茄子耐旱性相关的生理性状，设置了一个温室实验。基于来自菲律宾大学洛班纳分校植物育种研究所国家植物遗传资源实验室的前期田间和温室试验（58）中100个种质资源的耐旱表现，选择了Solanum melongena基因型PHL 4841、PHL 2778和PHL 2789。S. melongena ‘Mara’，该品种由洛班纳分校植物育种研究所发布，作为一个参考品种。种子于二月底在科罗拉多州科罗拉多斯普林斯的温室中播撒于装有碎陶土（Turface Greens Grade，Profile Products，美国伊利诺伊州巴佛洛，IL）的育苗盘中。经过17-21天幼苗生长后，将幼苗移植到装有10公斤碎陶土和水的7.57升塑料盆中，并通过滴灌将土壤水分调节至保持容量。盆栽放置在两个温室花架上，采用两个因素（水分供应：干旱与充足灌溉对照、基因型：四个基因型）的随机完全区组设计。每个区组有5个重复（40株植物）。该基本区组设计进行了加倍，植物在两个时间点（干旱后和恢复后）进行收获，共计80株植物。

植物在自然光照和补充LED照明的组合下维持，日夜间周期为14:10小时，平均温度为22和29°C。植物使用Grow More水溶性肥料（Grow More，Inc.，加利福尼亚州加登纳，CA）进行灌溉施肥，并添加尿素作为额外的氮源，以及添加KH2PO4作为额外的钾源，以达到移植后第一个月每天79.5-22.5-5 ppm N:P:K的比例，实验剩余部分调整为60-30-120 ppm N:P:K。

干旱处理始于移植后第5周，持续2周，适用于所有区组（80株植物）。‘干旱’植株在第一周每天接受30%的“对照”植株的蒸散量（ET），第二周为10%。‘对照’植株每天接受100%的ET。ET通过在1400小时每天称重对照盆来计算，以测量蒸发和蒸腾的水分损失相对于100%保持容量的相对值。干旱处理后，所有剩余的植物都被重新浇水至盆的保持容量。

生理测量：在干旱处理的第11天至第15天和最后一天，对实验植物种群中50%的干旱和对照植物进行随机测量。在每天07:30至08:30之间，使用便携式OS5P荧光计（Opti-Sciences Inc.，NH，USA）测量每株植物第三片充分展开的叶片的叶绿素荧光（Fv/Fm）。每片叶子在测量前用叶片夹进行20分钟的暗适应。从09:00至12:00，使用附有叶片测量室的Li-COR 6400XT红外气体分析仪（LiCOR Inc.，林肯，内布拉斯加州）测量同一叶片的光合速率、气孔导度和蒸腾作用。叶片测量室的条件如下：光合有效辐射（PAR）为1800 µmol m-2s-1，叶片温度为25˚C，二氧化碳浓度为400 µmol mol-1。瞬时水分利用效率（WUEi）按光合作用（An）与气孔导度（gs）的比率计算。

叶水势（ΨL）使用Scholander压力室（Soil Moisture Equipment Corp.，美国加利福尼亚州圣巴巴拉，CA）测定。从每株植物中切取与气体交换测量相同的叶子，并立即放入塑料袋中，放置在冷却器中，直到ΨL可以测量（最多1小时）。

在完全浇水一周后，“恢复”和对照植物再次进行上述测量，以测定叶绿素荧光和叶水势。

植物生长测量：在生理测量之后，干旱和对照植物地上部分被切割并分为叶片和茎。使用Li-3100C叶面积仪（LiCOR Inc.，USA）测量每株植物的总叶面积。然后将分割的茎组织在60˚C的烘箱中烘干48小时，并称重。

每个植物的地下生物量被洗净以去除碎陶土，并分为细根和粗根。从每个样本中获得细根的代表样本，并储存在30%乙醇中，以进行根扫描。保存的细根在水中以2-D透明模式使用台式扫描仪（EpsonV750，Epson America Inc.，USA）进行扫描，并使用WinRHIZOTM软件（Regent Instruments Inc.，加拿大）进行分析。剩余的细根和粗根按照上述方法进行烘干和称重。使用每株植物的叶数据计算叶面积比（总叶面积每总植物干重，平方米/克；LAR）、比叶面积（叶面积每叶干重，平方米/克；SLA）和叶质量面积（叶干重每叶面积，克/平方米；LMA）。使用每株植物的细根长度和根生物量数据计算特定细根长度（细根长度每干重，米/克；SRLFineRts）和总根质量分数（RMF，总根质量每总植物重量）。

在恢复阶段结束时，所有植物也进行了破坏性采样，以测量叶面积和地上及地下生物量分配，如上所述。

数据集资源：资源标题：来自《Solanum melongena L.（茄子）在干旱和干旱恢复期间最大化生长的植物策略》的数据。文件名：full_dataset.csv