DOI: 10.5061/dryad.6hdr7sr62
title: Nectar robbing by bees affects the reproductive fitness of the distylous plant Tirpitzia sinensis (Linaceae)

description: Nectar robbing can affect plant reproductive success directly by
 influencing female and male fitness, and indirectly by affecting
 pollinator behavior. Flowers have morphological and chemical features that
 may protect them from nectar robbers. Previous studies on nectar robbing
 have focused mainly on homotypic plants. It remains unclear how nectar
 robbing affects the reproductive success of distylous plants, and whether
 defense strategies of two morphs are different. Nectar robbing rates on
 the long- and short- styled morph (L-morph, S-morph) of the distylous
 Tirpitzia sinensis were investigated. We compared floral traits, the
 temporal pattern of change in nectar volume and sugar concentration,
 nectar secondary metabolites and sugar composition between robbed and
 unrobbed flowers of two morphs. We tested direct effects of nectar robbing
 on female and male components of plant fitness and the indirect effects of
 nectar robbing via pollinators. Nectar robbing rates did not differ
 between the two morphs. Flowers with smaller sepals and petals were more
 easily robbed. The floral tube diameter and thickness were greater in
 L-morphs than in S-morphs, and the nectar rob holes were significantly
 smaller in L-morphs than in S-morphs. Nectar robbing significantly
 decreased nectar replenishment rate but did not affect nectar sugar
 concentration or sugar composition. After robbery the quantities and
 diversity of secondary compounds in the nectar of S-morphs increased
 significantly and the total relative contents of secondary compounds in
 L-morphs showed no obvious changes. Nectar robbing could decrease female
 fitness by decreasing pollen germination and thus decreasing seed set.
 Nectar robbing had no significant effects on male fitness. Robbed flowers
 were less likely to be visited by hawkmoth pollinators, especially in
 S-morphs. These results suggest that nectar robbing could directly and
 indirectly decrease the female fitness of T. sinensis, and
 different morphs have evolved different defense mechanisms in response to
 nectar robbing pressure.
description: We collected the floral
 traits, the temporal pattern of change in nectar volume and sugar
 concentration, bee nectar robbing behavior, hawkmoth preference, female
 fitness, male fitness, nectar samples in the field. The nectar secondary
 metabolites and sugar composition were analyzed with Ultra Performance
 Liquid Chromatography-Quadrupole/time-of-flight mass spectrometers and
 High performance Liquid Chromatography
 respectively.
description: This README file was generated on 2023-10-12 by Xiaoyue Wang. GENERAL
 INFORMATION 1. Title of Dataset: Nectar robbing by bees affects the
 reproductive fitness of the distylous plant Tirpitzia sinensis (Linaceae)
 2. Author Information A. Principal Investigator Contact Information
 <br> Name: Xiaoyue Wang Institution: Guizhou Normal University
 Address: Guiyang, Guizhou Province, China Email: Wang.xiaoyue1989@163.com
 <br> B. Associate or Co-investigator Contact Information Name:
 Renxiu Yao Institution: Guizhou Normal University Address: Guiyang,
 Guizhou Province, China Email: 1660604198@qq.com Name: Xiaoqin Lv
 Institution: Guizhou Normal University Address: Guiyang, Guizhou Province,
 China Email: 2388571945@qq.com Name: Yin Yi Institution: Guizhou Normal
 University Address: Guiyang, Guizhou Province, China Email:
 gzklppdr@gznu.edu.cn Name: Xiaoxin Tang Institution: Guizhou Normal
 University Address: Guiyang, Guizhou Province, China Email:
 365397245@qq.com 3. Date of data collection (single date, range,
 approximate date): 2021-2022 4. Geographic location of data collection:
 Malipo county, Yunnan province, China 5. Information about funding sources
 that supported the collection of the data: National Natural Science
 Foundation of China (32360262, 31901208); The Joint Fund of the National
 Natural Science Foundation of China and the Karst Science Research Center
 of Guizhou Province(U1812401); The Science and Technology Foundation of
 Guizhou Province (2019/1237); and new seeding plants project of Guizhou
 Normal University (grant No. 2020). SHARING/ACCESS INFORMATION 1.
 Licenses/restrictions placed on the data: CC0 1.0 Universal (CC0 1.0)
 Public Domain 2. Links to publications that cite or use the data:
 <br> Wang, Xiaoyue et al. (Forthcoming 2023). Nectar robbing by bees
 affects the reproductive fitness of the distylous plant *Tirpitzia
 sinensis* (Linaceae). Ecology and Evolution. 3. Links to other publicly
 accessible locations of the data: None 4. Links/relationships to ancillary
 data sets: None 5. Was data derived from another source? No A. If yes,
 list source(s): NA 6. Recommended citation for this dataset: Wang, X.Y,
 Yao R.X., Lv, X.Q, Yi, Y, Tang, X.X. (Forthcoming 2023). Data from: Nectar
 robbing by bees affects the reproductive fitness of the distylous plant
 Tirpitzia sinensis (Linaceae). Dryad Digital Repository.
 https://doi.org/10.5061/dryad.6hdr7sr62 DATA & FILE OVERVIEW 1.
 File List: 1. nectar robbing rate 1011 .xls 2. floral traits of Tirpitzia
 sinensis 1011 .xls 3. the temporal pattern of variation in nectar volume
 and sugar concentration between robbed and unrobbed flowers of the two
 morphs（0800-2000) 1011 .xls 4. chemical compounds tentatively identified
 1011 .xls 5. nectar sugar composition 1011 .xls 6. visit rate of nectar
 robbers 1011 .xls 7. pollen germination (female fitness) 1011 .xls 8.
 pollen tube length (female fitness) 1011 .xls 9. seed set (female
 fitness)1011 .xls 10. pollen production and pollen quality (male fitness)
 1011 .xls 11. visit frequency of hawkmoths 1011 .xls 2. Relationship
 between files, if important: None 3. Additional related data collected
 that was not included in the current data package: None 4. Are there
 multiple versions of the dataset? No A. If yes, name of file(s) that was
 updated: NA i. Why was the file updated? NA ii. When was the file updated?
 NA
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: nectar robbing rate 1011. xls these data
 was used to compare the nectar robbing rate between the Long- styled morph
 (hereafter L- morph ) and Short- styled morph (hereafter S- morph). 1.
 Number of variables: 3 2. Number of cases/rows: 180 3. Variable List: *
 nectar robbing rate (%): the natural nectar robbing rate between L- and S-
 morphs in wild populations. * L-morph(1) S-morph(2): L-morph was replaced
 with 1, S- morph was replaced with 2. * population: there were three
 populations where data collected. 4. Missing data codes: None 5.
 Specialized formats or other abbreviations used: None
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: floral traits of *Tirpitzia sinensis*
 1011\. xls these data was used to compare floral traits between the robbed
 and unrobbed flowers of the L- and S- morphs. 1. Number of variables: 17
 2. Number of cases/rows: 120 3. Variable List: * flower length(mm): the
 flower length of *Tirpitzia sinensis* * flower width(mm): the flower width
 of *Tirpitzia sinensis* * petal length(mm): the petal length of *Tirpitzia
 sinensis* * petal width(mm): the petal width of *Tirpitzia sinensis* *
 tube depth(mm): the floral tube depth of *Tirpitzia sinensis* * tube
 diameter(mm): the floral tube diameter of *Tirpitzia sinensis* * Opening
 diameter (mm): the floral opening diameter of *Tirpitzia sinensis* *
 Pistil length(mm): the pistil length of *Tirpitzia sinensis* * Stamen
 length(mm): the stamen length of *Tirpitzia sinensis* * Sepal length(mm):
 the sepal length of *Tirpitzia sinensis* * Sepal width(mm): the sepal
 width of *Tirpitzia sinensis* * Tube thickness(mm): the floral tube
 thickness of *Tirpitzia sinensis* * unrobded flower (1) robbed flower (2):
 the unrobbed flower was replaced with 1, the robbed flower was replaced
 with 2. * L- morph (1) S- morph (2) （floral trait) : the comparison of
 flowers traits between L- and S- morphs. the L- morph was replaced with 1,
 the S- morph was replaced with 2. * Nectar rob hole length(mm): the nectar
 rob hole length of *Tirpitzia sinensis*. * Nectar rob hole width(mm): the
 nectar rob hole width of *Tirpitzia sinensis*. * L-morph (1) S-morph (2)
 (nectar rob hole): the comparison of nectar rob hole between L- and S-
 morphs. the L- morph was replaced with 1, the S- morph was replaced with
 2. 4. Missing data codes: NA (data not available) 5. Specialized formats
 or other abbreviations used: None
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: the temporal pattern of variation in nectar
 volume and sugar concentration between robbed and unrobbed flowers of the
 two morphs（0800-2000) 1011. xls These are the data used to determine the
 temporal patterns of nectar availability. 1. Number of variables: 10 2.
 Number of cases/rows: 305 3. Variable List: * nectar volume (mL): the
 nectar volume of *Tirpitzia sinensis* * treated time for nectar volume:
 the time when we measured the nectar volume. 0800 h was replaces with 1,
 1100 h was replaces with 2, 1400 h was replaces with 3 , 1700 h was
 replaces with 4 and 2000 h was replaces with 5. * unrobbed flower(1)
 robbed flower (2) for nectar volume: the comparison of the nectar volume
 between unrobbed flower robbed flower. the unrobbed flower was replaced
 with 1, the robbed flower was replaced with 2. * L-morph (1) S-morph (2)
 for nectar volume: the comparison of nectar volume between L- and S-
 morphs. the L- morph was replaced with 1, the S- morph was replaced with
 2. * nectar sugar concentration (%): the nectar sugar concentration of
 *Tirpitzia sinensis*. * treated time for nectar sugar concentration: the
 time when we measured the nectar sugar concentration. 0800 h was replaces
 with 1, 1100 h was replaces with 2, 1400 h was replaces with 3 , 1700 h
 was replaces with 4 and 2000 h was replaces with 5. * unrobbed flower(1)
 robbed flower (2) for nectar sugar concentration: the comparison of the
 nectar sugar concentration between unrobbed flower robbed flower. the
 unrobbed flower was replaced with 1, the robbed flower was replaced with
 2. * L-morph (1) S-morph (2) for nectar sugar concentration: the
 comparison of nectar sugar concentration between L- and S- morphs. the L-
 morph was replaced with 1, the S- morph was replaced with 2. * number: 1,
 2, 3, 4, 5. the different number present the different time. 0800 h was
 replaces with 1, 1100 h was replaces with 2, 1400 h was replaces with 3 ,
 1700 h was replaces with 4 and 2000 h was replaces with 5. * treated time:
 the time when we measured the nectar volume and sugar concentration. 4.
 Missing data codes: NA (data not applicable) 5. Specialized formats or
 other abbreviations used: None.
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: chemical compounds tentatively identified
 1011.xls these data showed all the chemical compounds tentatively
 identified in the nectar of robbed and unrobbed flowers of the L- and S-
 morphs in *Tirpitzia sinensis*. 1. Number of variables: 7 2. Number of
 cases/rows: 221 3. Variable List: * Category: These components could be
 divided into 10 different types: terpenoids (72 chemical compounds),
 alkaloids (32 compounds), flavonoids (29 compounds), glycosides (25
 compounds), phenylpropanoids (19 compounds), steroids (18 compounds),
 fatty acids (16 compounds), alcohols (3 compounds), aldehydes (5
 compounds) and phenanthrenes (2 compounds). * Compounds: the English name
 of the chemical compounds. * Chemical formula: the chemical formula of the
 chemical compounds. * Response value for unrobbed L-morph: the response
 value of the chemical compounds of the nectar from unrobbed flowers in L-
 morph of *Tirpitzia sinensis*. * Response value for robbed L-morph: the
 response value of the chemical compounds of the nectar from robbed flowers
 in L- morph of *Tirpitzia sinensis*. * Response value for unrobbed
 S-morph: the response value of the chemical compounds of the nectar from
 unrobbed flowers in S- morph of *Tirpitzia sinensis*. * Response value for
 robbed S-morph: the response value of the chemical compounds of the nectar
 from robbed flowers in S- morph of *Tirpitzia sinensis*. 4. Missing data
 codes: None 5. Specialized formats or other abbreviations used: the number
 of samples (n) in which each compound was found in floral nectar (5 in
 total) was listed in the parenthesis. "/" means that the
 chemical compound was not detected in the sample.
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: nectar sugar composition 1011.xls the data
 showed that the nectar sugars (glucose, fructose, sucrose) contents (g/mL)
 of the L- and S- morphs in *Tirpitzia sinensis* from flowers with obvious
 rob holes and flowers from undamaged flowers. 1. Number of variables: 6 2.
 Number of cases/rows: 37 3. Variable List: * fructose: the fructose
 contents (g/mL) in the nectar. * glucose: the glucose contents (g/mL) in
 the nectar. * sucrose: the glucose contents (g/mL) in the nectar. *
 unrobbed L- morph (1) robbed L-morph (2) unrobbed S-morph (3) robbed
 S-morph (4): the comparison of nectar sugar contents among different
 treatments. unrobbed L- morph was replaced with 1. robbed L-morph was
 replaced with unrobbed S-morph. unrobbed S-morph was replaced with 3.
 robbed S-morph was replaced with 4. * unrobbed (1) robbed (2): the
 comparison of nectar sugar contents between *Tirpitzia sinensis* flowers
 with obvious rob holes (robbed) and flowers from undamaged flowers
 (unrobbed). unrobbed was replaced with 1. robbed was replaced with 2. *
 L-morph (1) S-morph (2): the comparison of nectar sugar contents between
 L- and S- morph in Tirpitzia sinensis. L- morph was replaced with 1. S-
 morph was replaced with 2. 4. Missing data codes: NA (data not available)
 5. Specialized formats or other abbreviations used: None
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: visit rate of nectar robbers 1011.xls The
 data showed the visit rate of nectar robbers *Bombus breviceps* and
 *Xylocopa sinensis* to L- and S- morphs in Tirpitzia sinensis. 1. Number
 of variables: 3 2. Number of cases/rows: 92 3. Variable List: * visit
 rates: the visit rates of nectar robbers. * *Bombus breviceps*(1)
 *Xylocopa sinensis*(2): the nectar robber in *Tirpitzia sinensis*: *Bombus
 breviceps* and *Xylocopa sinensis*. *Bombus breviceps* was replaced with
 1. *Xylocopa sinensis* was replaced with 2. * S-morph (1) L-morph (2): the
 comparison of visit rates to S- and L- morphs. the S- morph was replaced
 with 1. the L- morph was replaced with 2. 4. Missing data codes: None 5.
 Specialized formats or other abbreviations used: None
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: pollen germination (female fitness)
 1011.xls the data showed the pollen germination rate (%) under intermorph
 pollination, intermorph pollination of pollen recipients with rob holes,
 intermorph pollination of pollen recipients after nectar removal in both
 L- and S- morph of *Tirpitzia sinensis*. 1. Number of variables: 3 2.
 Number of cases/rows: 169 3. Variable List: * pollen germination rate（%）:
 the pollen germination rate (%) of *Tirpitzia sinensis*. * intermorph
 pollination (1) intermorph pollination of pollen recipients with rob holes
 (2) intermorph pollination of pollen recipients after nectar removal (3):
 the comparison of pollen germination rate among different pollination
 treatments. intermorph pollination was replaced with 1. intermorph
 pollination of pollen recipients with rob holes was replaced with 2.
 intermorph pollination of pollen recipients after nectar removal was
 replaced with 3. * L- morph (1) S- morph (2): the comparison of pollen
 germination rate between L- and S- morph. L- morph was replaced with 1. S-
 morph was replaced with 2. 4. Missing data codes: None 5. Specialized
 formats or other abbreviations used: None
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: pollen tube length (female fitness)
 1011.xls the data showed the pollen tube length under intermorph
 pollination, intermorph pollination of pollen recipients with rob holes,
 intermorph pollination of pollen recipients after nectar removal in both
 L- and S- morph of *Tirpitzia sinensis*. 1. Number of variables: 3 2.
 Number of cases/rows: 179 3. Variable List: * pollen tube length (mm):
 pollen tube length (mm) of *Tirpitzia sinensis*. * intermorph pollination
 (1) intermorph pollination of pollen recipients with rob holes (2)
 intermorph pollination of pollen recipients after nectar removal (3): the
 comparison of pollen tube length among different pollination treatments.
 intermorph pollination was replaced with 1. intermorph pollination of
 pollen recipients with rob holes was replaced with 2. intermorph
 pollination of pollen recipients after nectar removal was replaced with 3.
 * L- morph (1) S- morph (2): the comparison of pollen tube length between
 L- and S- morph. L- morph was replaced with 1. S- morph was replaced with
 2. 4. *Missing* data codes: None 5. Specialized formats or other
 abbreviations used: None
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: seed set (female fitness)1011.xls the data
 showed the seed set (female fitness) under control, naturally robbed,
 intermorph pollination, intermorph pollination of pollen recipients with
 rob holes, intermorph pollination of pollen recipients after nectar
 removal in both L- and S- morph of *Tirpitzia sinensis*. 1. Number of
 variables: 5 2. Number of cases/rows: 412 3. Variable List: * seed set(%):
 the seed set (%) of *Tirpitzia sinensis* * treatments: the different
 pollination treatments. * L-morph (1) S-morph (2): the comparison of seed
 set between L- and S- morphs. L-morph was replaced with 1. S-morph was
 replaced with 2. * number: 1,2,3,4,5. the number represents different
 pollination treatments. 1= control, 2 = naturally robbed, 3 = intermorph
 pollination, 4 = intermorph pollination of pollen recipients with rob
 holes, 5 = intermorph pollination of pollen recipients after nectar
 removal. * the meaning for treatments: the different pollination
 treatments. 4. Missing data codes: NA (data not available) 5. Specialized
 formats or other abbreviations used: None
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: pollen production and pollen quality (male
 fitness) 1011.xls the data showed the pollen production of normal buds and
 buds with obvious nectar rob holes, and the seed set under control,
 intermorph pollination, intermorph pollination by robbed pollen donors in
 both L- and S- morph of *Tirpitzia sinensis*. This dataset was used to
 create Figure 3. 1. Number of variables: 8 2. Number of cases/rows: 252 3.
 Variable List: * number of pollen grains: the number of pollen grains of
 *Tirpitzia sinensis*. * control(1) with rob hole (2): the comparison of
 number of pollen grains between normal buds (control) and buds with rob
 hole. the control was replaced with 1. the buds with rob hole was replaced
 with 2. * L-morph (1) S-morph (2) for number of pollen grains: the
 comparison of number of pollen grains between L- and S- morphs. L-morph
 was replaced with 1. S-morph was replaced with 2. * seed set(%): the seed
 set (%) of *Tirpitzia sinensis*. * treatments: different pollination
 treatments. * L-morph (1) S-morph (2) for seed set: the comparison of seed
 set between L- and S- morphs. L-morph was replaced with 1. S-morph was
 replaced with 2. * number: 1,2,3. the number represents different
 pollination treatments. 1 = control, 2 = intermorph pollination, 3 =
 intermorph pollination by robbed pollen donors * the meaning for
 treatments: the different pollination treatments. 4. Missing data codes:
 None 5. Specialized formats or other abbreviations used: None
 #########################################################################
 DATA-SPECIFIC INFORMATION FOR: visit frequency of hawkmoths 1011.xls this
 data showed the visit frequency of hawkmoths (%) to unrobbed flower and
 robbed flower of *Tirpitzia sinensis* in L- and S- morph. 1. Number of
 variables: 3 2. Number of cases/rows: 54 3. Variable List: * visit
 frequency of hawkmoths (%): the visit frequency of hawkmoths (%) to
 \**Tirpitzia sinensis* lowers * unrobbed flower (1) robbed flower (2): the
 comparison of visit frequency of hawkmoths to unrobbed flower and robbed
 flower. the unrobbed flower was replaced with 1 and the robbed flower was
 replaced with 2. * L-morph (1) S-morph (2): the comparison of visit
 frequency of hawkmoths to L-morph and S-morph. L-morph was replaced with 1
 and S-morph was replaced 2. 4. Missing data codes: NA (not applicable) 5.
 Specialized formats or other abbreviations used: None