Spatial repellency effects of Taiwanese plant oils on the biting midge, Forcipomyia taiwana

Figures & data

Table 1. Results of the Y-tube olfactometer tests with F. taiwana.

Scientific name	Source	Solvent	Knock	Mean ± SE RI0µL	Mean ± SE RI10µL	Mean ± SE RI50µL	Anova F-stat	Sig.
Acacia confusa Merr. (Fabaceae)	TBG	Hex	0	0.016 ± 0.10	−0.003 ± 0.13	0.004 ± 0.28	F(2,9) = 0.01059
		EtAc	0	−0.087 ± 0.19	−0.009 ± 0.17	−0.022 ± 0.33	F(2,9) = 0.1183
Artemisia absinthium L. (Asteraceae)	OIC		4.86%	−0.022 ± 0.11	−0.154 ± 0.07	−0.342 ± 0.13	F(2,9) = 9.2800	**
Artemisia capillaris Thunb. (Asteraceae)	TNF	Hex	0	−0.020 ± 0.14	−0.084 ± 0.17	−0.290 ± 0.10	F(2,9) = 4.1065	•
		EtAc	0	0.073 ± 0.22	0.081 ± 0.12	−0.298 ± 0.20	F(2,9) = 5.6380	*
Azadirachta indica L. A.Juss. (Meliaceae) seed	OIC		0	−0.027 ± 0.12	−0.053 ± 0.09	−0.132 ± 0.22	F(2,9) = 0.5120
Bidens alba (L.) DC. (Asteraceae)	NTU	Hex	0	−0.001 ± 0.06	−0.001 ± 0.06	−0.036 ± 0.21	F(2,9) = 0.0942
		EtAc	0	−0.061 ± 0.06	−0.132 ± 0.10	−0.186 ± 0.11	F(2,9) = 1.8063
Calocedrus formosana (Florin) (Cupressaceae)	NTU	Hex	0	−0.064 ± 0.05	0.037 ± 0.11	−0.005 ± 0.15	F(2,9) = 0.8650
		EtAc	0	0.066 ± 0.09	0.032 ± 0.16	−0.078 ± 0.10	F(2,9) = 1.5931
Camellia sinensis L. (Theaceae)	FSI		0	0.117 ± 0.21	−0.064 ± 0.29	−0.284 ± 0.42	F(2,9) = 1.5951
Chamaecyparis formosensis Matsum. (Cupressaceae) leaves	TNF	Hex	0	0.073 ± 0.14	−0.116 ± 0.23	−0.049 ± 0.12	F(2,9) = 1.2812
		EtAc	0	0.040 ± 0.12	−0.098 ± 0.20	−0.220 ± 0.31	F(2,9) = 1.3366
Chamaecyparis formosensis Matsum. (Cupressaceae) wood	OIC		0	−0.004 ± 0.14	−0.135 ± 0.13	−0.513 ± 0.19	F(2,9) = 11.763	**
Cinnamomum camphora (L.) J.Presl (Lauraceae) bark	OIC		0	−0.058 ± 0.08	−0.295 ± 0.19	−0.354 ± 0.22	F(2,9) = 3.2951	•
Cinnamomum camphora (L.) J.Presl (Lauraceae) leaves	NTU	Hex	0	0.058 ± 0.14	−0.114 ± 0.20	−0.459 ± 0.11	F(2,9) = 11.249	**
		EtAc	0	−0.057 ± 0.15	−0.180 ± 0.06	−0.214 ± 0.04	F(2,9) = 2.9913
Cinnamomum osmophloeum Kaneh. (Lauraceae)	TBG	Hex	0	−0.005 ± 0.21	−0.127 ± 0.09	−0.117 ± 0.21	F(2,9) = 0.5694
		EtAc	0	−0.017 ± 0.16	−0.032 ± 0.17	−0.057 ± 0.13	F(2,9) = 0.0682
Clausena excavata Burm.f. (Rutaceae)	NTU	Hex	0	−0.022 ± 0.11	0.188 ± 0.11	0.037 ± 0.24	F(2,9) = 1.7185
		EtAc	0	0.101 ± 0.11	−0.192 ± 0.09	−0.057 ± 0.12	F(2,9) = 7.5759	*
Corymbia citriodora (Hook.) K.D.Hill & L.A.S.Johnson (Myrtaceae)	NTU	Hex	0	0.008 ± 0.09	−0.106 ± 0.05	−0.303 ± 0.31	F(2,9) = 2.7585
		EtAc	0	0.015 ± 0.05	−0.012 ± 0.08	−0.129 ± 0.17	F(2,9) = 1.8944
Cryptomeria japonica (Thunb. ex L.f.) D.Don (Cupressaceae)	TNF	Hex	0	−0.083 ± 0.07	−0.081 ± 0.20	−0.074 ± 0.24	F(2,9) = 0.0021
		EtAc	0	−0.004 ± 0.14	0.075 ± 0.06	0.086 ± 0.16	F(2,9) = 0.5688
Cunninghamia konishii Hayata (Cupressaceae)	TNF	Hex	0	0.037 ± 0.10	0.024 ± 0.17	0.197 ± 0.14	F(2,9) = 1.8844
		EtAc	1.79%	0.012 ± 0.13	−0.099 ± 0.22	0.051 ± 0.21	F(2,9) = 0.6735
Cymbopogon nardus (L.) Rendle (Poaceae)	OIC		0	−0.031 ± 0.22	−0.447 ± 0.21	−0.613 ± 0.22	F(2,9) = 7.5596	*
Dimocarpus longan Lour. (Sapindaceae)	NTU	Hex	0	0.043 ± 0.06	0.073 ± 0.09	−0.007 ± 0.16	F(2,9) = 0.5507
		EtAc	2.94%	0.003 ± 0.10	0.004 ± 0.19	−0.010 ± 0.14	F(2,9) = 0.0114
Eucalyptus robusta Sm. (Myrtaceae)	NTU	Hex	0	−0.017 ± 0.03	−0.014 ± 0.10	−0.062 ± 0.13	F(2,9) = 0.3392
		EtAc	2.17%	−0.014 ± 0.05	0.037 ± 0.07	0.026 ± 0.10	F(2,9) = 0.5172
Eucalyptus sp. L'Hér (Myrtaceae)	FSI		0	−0.023 ± 0.08	−0.239 ± 0.34	−0.505 ± 0.24	F(2,9) = 3.8868	•
Eupatorium formosanum Hayata (Asteraceae)	TNF	Hex	0	−0.091 ± 0.03	0.001 ± 0.10	0.036 ± 0.16	F(2,9) = 1.4193
		EtAc	0	−0.160 ± 0.18	−0.006 ± 0.27	−0.107 ± 0.22	F(2,9) = 0.4822
Ficus septica Burm.f. (Moraceae)	NTU	Hex	0	0.016 ± 0.18	−0.023 ± 0.10	−0.047 ± 0.19	F(2,9) = 0.1557
		EtAc	0	0.038 ± 0.07	0.078 ± 0.15	0.141 ± 0.13	F(2,9) = 0.7240
Lagerstroemia indica L. (Lythraceae)	NTU	Hex	0	0.088 ± 0.14	−0.064 ± 0.11	−0.032 ± 0.30	F(2,9) = 0.6417
		EtAc	0	−0.028 ± 0.12	−0.057 ± 0.13	−0.136 ± 0.21	F(2,9) = 0.5143
Lantana camara L. (Verbenaceae)	NTU	Hex	0	0.048 ± 0.10	0.063 ± 0.08	0.065 ± 0.18	F(2,9) = 0.0220
		EtAc	0	−0.006 ± 0.16	−0.063 + 0.22	−0.128 + 0.14	F(2,9) = 0.4631
Lavandula angustifolia Chaix ex Vill. Mill.(Lamiaceae)	OIC		1.09%	0.061 ± 0.05	−0.301 ± 0.19	−0.518 ± 0.15	F(2,9) = 16.292	**
Leucaena leucocephala (Lam.) de Wit (Fabaceae)	NTU	Hex	0	−0.067 ± 0.14	−0.044 ± 0.31	−0.039 ± 0.26	F(2,9) = 0.0148
		EtAc	0	−0.034 ± 0.04	0.046 ± 0.16	−0.203 ± 0.40	F(2,9) = 1.0248
Macaranga tanarius (L.) Muell.Arg. (Euphorbiaceae)	NTU	Hex	0	0.050 ± 0.27	−0.183 ± 0.24	0.022 ± 0.16	F(2,9) = 1.2376
		EtAc	0	−0.056 ± 0.13	−0.139 ± 0.12	−0.084 ± 0.14	F(2,9) = 0.4109
Mangifera indica L. (Anacardiaceae)	NTU	Hex	0	0.087 ± 0.05	0.101 ± 0.16	0.051 ± 0.22	F(2,9) = 0.1028
		EtAc	0	−0.000 ± 0.11	0.018 + 0.17	−0.020 ± 0.30	F(2,9) = 0.0327
Melaleuca cajuputi Powell (Myrtaceae)	OIC		8.11%	0.053 ± 0.10	−0.027 ± 0.12	−0.303 ± 0.18	F(2,9) = 7.4107	*
Melaleuca leucadendra L. (Myrtaceae)	NTU	Hex	0	0.019 ± 0.09	−0.117 ± 0.23	−0.067 ± 0.06	F(2,9) = 0.9139
		EtAc	0	−0.066 ± 0.13	−0.088 + 0.09	−0.090 ± 0.02	F(2,9) = 0.0870
Melissa officinalis L. (Lamiaceae)	FSI		0	−0.001 ± 0.07	−0.154 ± 0.26	−0.505 ± 0.11	F(2,9) = 9.7249	**
Mentha canadensis L. (Lamiaceae)	FSI		0	0.015 ± 0.03	−0.095 ± 0.08	−0.241 ± 0.13	F(2,9) = 7.9800	*
Mikania micrantha Kunth (Asteraceae)	NTU	Hex	0	−0.028 ± 0.03	0.010 ± 0.18	−0.051 ± 0.17	F(2,9) = 0.1804
		EtAc	1.67%	0.031 ± 0.08	0.024 ± 0.22	0.048 ± 0.03	F(2,9) = 0.0338
Ocimum basilicum L. (Lamiaceae)	OIC		0	0.035 ± 0.09	−0.237 ± 0.18	−0.352 ± 0.26	F(2,12) = 6.5048	*
Pelargonium sp. L'Her. ex Aiton (Geraniaceae)	FSI		0	0.097 ± 0.08	−0.071 ± 0.26	−0.389 ± 0.29	F(2,9) = 4.5269	*
Pittosporum pentandrum (Blanco) Merr. (Pittosporaceae)	TBG	Hex	0	−0.030 ± 0.08	0.019 ± 0.16	−0.000 ± 0.13	F(2,9) = 0.1493
		EtAc	1.79%	0.014 ± 0.11	−0.092 ± 0.08	−0.132 ± 0.11	F(2,9) = 2.3314
Pogostemon cablin (Blanco) Benth. (Lamiaceae)	OIC		0	−0.060 ± 0.10	−0.038 ± 0.14	−0.135 ± 0.21	F(2,15) = 0.6350
Salvia rosmarinus (L.) Schleid. (Lamiaceae)	OIC		6.23%	0.092 ± 0.06	−0.144 ± 0.13	−0.324 ± 0.20	F(2,9) = 8.6026	**
Santalum album L. (Santalaceae)	OIC		0	0.000 ± 0.00	0.001 ± 0.04	−0.013 ± 0.15	F(2,9) = 0.0296
Setaria palmifolia (J.Koenig) Stapf (Poaceae)	TNF	Hex	0	0.031 ± 0.14	−0.071 ± 0.12	−0.095 ± 0.12	F(2,9) = 1.1127
		EtAc	0	0.123 ± 0.12	0.047 ± 0.10	−0.150 ± 0.10	F(2,9) = 6.9506	*
Syzygium aromaticum (L.) Merr. & L.M.Perry (Myrtaceae) bud	OIC		0	0.038 ± 0.10	−0.201 ± 0.12	−0.327 ± 0.29	F(2,8) = 3.4600	•
Syzygium aromaticum (L.) Merr. & L.M.Perry (Myrtaceae) leaf	OIC		17.33%	0.108 ± 0.14	−0.236 ± 0.31	−0.241 ± 0.38	F(2,9) = 1.8802
Taiwania cryptomerioides Hayata (Cupressaceae)	TNF	Hex	0	0.071 ± 0.10	0.158 ± 0.13	0.081 ± 0.13	F(2,9) = 0.6424
		EtAc	0	0.063 ± 0.14	−0.142 ± 0.07	−0.271 ± 0.16	F(2,9) = 6.9420	*

Commercial oils were tested with ethanol as negative control. Because the flies did not always distribute themselves perfectly randomly in control Y-tubes, repellency index values are given at 0 [control], 10, and 50 µL applications. Means are of ≥ four independent Y-tube per application amount. Sources: FSI = Fusheng Instrument Co., Ltd. [commercially-produced essential oil]; NTU = National Taiwan University campus [collections in summer of 2020 or 2021]; OIC = O’ddenio International Company [commercially-produced essential oil]; TBG = Taipei Botanical Garden [collected 8 April 2021]; TNF = Taipingshan National Forest [collected 6 August 2021]. EtAc = Ethyl acetate. Hex = Hexane. SE = Standard Error. RI = Repellency index. Knock = Mean knockdown percentage at 50 µL doses. Sig. =  Significance (p-values) of the ANOVA test comparing the three concentrations: • - p < 0.1 * - p < 0.05 ** - p < 0.01 *** - p < 0.001

Table 2. Mean percentage of F. taiwana that made decisions in the Y-olfactometer tests.

Scientific name	Source	Solvent	Mean ± SE % dec. 0 µL	Mean ± SE % dec. 10 µL	Mean ± SE % dec. 50 µL	ANOVA F stat	sig
Acacia confusa (Fabaceae)	TBG	Hex	31.81 ± 13.60	45.39 ± 15.36	53.82 ± 18.78	F(2,9) = 1.91388
		EtAc	25.94 ± 4.45	36.19 ± 12.14	55.62 ± 10.06	F(2,9) = 4.78984	*
Artemisia absinthium (Asteraceae)	OIC		23.61 ± 11.75	38.54 ± 18.94	64.56 ± 10.82	F(2,9) = 8.39474	**
Artemisia capillaris (Asteraceae)	TNF	Hex	22.28 ± 7.41	46.38 ± 14.25	55.75 ± 7.06	F(2,9) = 11.62051	**
		EtAc	35.20 ± 10.25	53.86 ± 10.92	46.89 ± 7.84	F(2,9) = 3.73435	•
Azadirachta indica (Meliaceae) seed	OIC		19.06 ± 5.64	47.25 ± 7.02	65.84 ± 8.00	F(2,9) = 45.88594	***
Bidens alba (Asteraceae)	NTU	Hex	3.45 ± 3.99	20.83 ± 9.92	38.10 ± 14.00	F(2,9) = 11.60787	**
		EtAc	27.11 ± 4.47	35.88 ± 8.25	43.05 ± 11.09	F(2,9) = 3.62061	•
Calocedrus formosana (Cupressaceae)	NTU	Hex	18.76 ± 8.64	23.00 ± 13.74	29.95 ± 11.97	F(2,9) = 0.94225
		EtAc	15.72 ± 16.68	16.57 ± 11.31	29.23 ± 6.73	F(2,9) = 1.52049
Camellia sinensis (Theaceae)	FSI		40.22 ± 19.73	67.63 ± 13.87	69.39 ± 10.39	F(2,9) = 4.65248	*
Chamaecyparis formosensis (Cupressaceae) leaves	TNF	Hex	31.84 ± 7.51	51.52 ± 10.63	51.16 ± 15.53	F(2,9) = 3.70696	•
		EtAc	31.10 ± 13.17	41.20 ± 16.09	48.01 ± 9.58	F(2,9) = 1.65647
Chamaecyparis formosensis (Cupressaceae) wood	OIC		29.78 ± 12.42	55.87 ± 26.48	72.65 ± 19.76	F(2,9) = 4.49554	*
Cinnamomum camphora (Lauraceae) bark	OIC		39.17 ± 25.44	54.24 ± 23.34	67.36 ± 12.50	F(2,9) = 1.7718
Cinnamomum camphora (Lauraceae) leaves	NTU	Hex	23.21 ± 12.41	42.76 ± 10.85	50.48 ± 7.64	F(2,9) = 7.18381	*
		EtAc	32.00 ± 10.86	34.01 ± 5.65	39.86 ± 7.39	F(2,9) = 0.9779
Cinnamomum osmophloeum (Lauraceae)	TBG	Hex	30.10 ± 17.46	41.36 ± 14.24	44.97 ± 24.21	F(2,9) = 0.66054
		EtAc	32.57 ± 20.69	35.42 ± 17.80	54.36 ± 12.43	F(2,9) = 1.87097
Clausena excavata (Rutaceae)	NTU	Hex	26.15 ± 20.03	48.40 ± 11.77	55.98 ± 1.94	F(2,9) = 5.31015	*
		EtAc	23.18 ± 14.87	33.08 ± 8.85	47.28 ± 13.29	F(2,9) = 3.70282	•
Corymbia citriodora (Myrtaceae)	NTU	Hex	32.64 ± 22.62	51.06 ± 21.65	56.52 ± 18.26	F(2,9) = 1.42786
		EtAc	9.97 ± 8.62	12.47 ± 5.73	21.74 ± 10.07	F(2,9) = 2.21509
Cryptomeria japonica (Cupressaceae)	TNF	Hex	36.34 ± 18.73	40.81 ± 10.27	44.75 ± 12.28	F(2,9) = 0.35042
		EtAc	34.14 ± 21.54	40.55 ± 9.62	55.46 ± 8.75	F(2,9) = 2.26678
Cunninghamia konishii (Cupressaceae)	TNF	Hex	36.34 ± 18.73	40.81 ± 10.27	44.75 ± 12.28	F(2,9) = 0.35042
		EtAc	39.29 ± 9.22	50.24 ± 12.82	60.42 ± 12.95	F(2,9) = 3.21481	•
Cymbopogon nardus (Poaceae)	OIC		40.78 ± 19.69	54.15 ± 20.43	67.22 ± 15.67	F(2,9) = 1.99614
Dimocarpus longan (Sapindaceae)	NTU	Hex	22.11 ± 18.61	28.33 ± 15.46	30.09 ± 22.26	F(2,9) = 0.33679
		EtAc	25.09 ± 10.88	33.33 ± 16.67	38.67 ± 20.84	F(2,9) = 0.67576
Eucalyptus robusta (Myrtaceae)	NTU	Hex	19.36 ± 13.65	26.18 ± 20.14	33.25 ± 17.68	F(2,9) = 0.64033
		EtAc	27.28 ± 22.80	32.40 ± 8.29	46.66 ± 10.38	F(2,9) = 1.73751
Eucalyptus sp. (Myrtaceae)	FSI		26.21 ± 21.73	37.10 ± 26.69	50.54 ± 23.86	F(2,9) = 1.01642
Eupatorium formosanum (Asteraceae)	TNF	Hex	18.51 ± 12.19	31.55 ± 13.23	37.16 ± 27.19	F(2,9) = 1.03311
		EtAc	38.69 ± 14.28	61.15 ± 5.39	53.12 ± 10.99	F(2,9) = 4.39045	*
Ficus septica (Moraceae)	NTU	Hex	22.94 ± 7.37	46.42 ± 16.16	60.62 ± 22.44	F(2,9) = 5.30642	*
		EtAc	9.90 ± 4.82	22.85 ± 11.26	22.40 ± 12.16	F(2,9) = 2.17562
Lagerstroemia indica (Lythraceae)	NTU	Hex	29.32 ± 12.69	58.29 ± 29.79	53.32 ± 11.89	F(2,9) = 2.42157
		EtAc	17.45 ± 4.46	38.43 ± 12.30	48.08 ± 19.37	F(2,9) = 5.38382	*
Lantana camara (Verbenaceae)	NTU	Hex	35.46 ± 18.36	49.87 ± 13.95	54.82 ± 14.94	F(2,9) = 1.6101
		EtAc	28.43 ± 13.79	54.11 ± 17.37	66.03 ± 14.01	F(2,9) = 6.43507	*
Lavandula angustifolia (Lamiaceae)	OIC		15.63 ± 11.14	46.42 ± 13.08	66.45 ± 10.23	F(2,9) = 19.68179	***
Leucaena leucocephala (Fabaceae)	NTU	Hex	33.85 ± 18.94	44.87 ± 6.34	58.72 ± 11.49	F(2,9) = 3.50955	•
		EtAc	14.61 ± 14.04	29.95 ± 11.59	59.15 ± 14.11	F(2,9) = 11.57994	**
Macaranga tanarius (Euphorbiaceae)	NTU	Hex	32.75 ± 9.58	57.51 ± 22.83	73.56 ± 14.86	F(2,9) = 6.08192	*
		EtAc	23.06 ± 6.36	28.04 ± 8.58	44.26 ± 7.44	F(2,9) = 8.71042	**
Mangifera indica (Anacardiaceae)	NTU	Hex	14.55 ± 5.55	22.21 ± 12.78	29.75 ± 23.34	F(2,9) = 0.93809
		EtAc	13.29 ± 3.23	35.03 ± 5.14	42.23 ± 5.98	F(2,9) = 37.5355	***
Melaleuca cajuputi (Myrtaceae)	OIC		38.32 ± 16.46	56.31 ± 19.29	70.55 ± 12.11	F(2,9) = 3.96452	•
Melaleuca leucadendra (Myrtaceae)	NTU	Hex	22.34 ± 14.15	35.08 ± 17.82	40.05 ± 1.98	F(2,9) = 1.92014
		EtAc	17.81 ± 10.59	30.79 ± 13.57	24.97 ± 14.57	F(2,9) = 0.99854
Melissa officinalis (Lamiaceae)	FSI		26.35 ± 14.16	38.44 ± 13.75	53.65 ± 10.36	F(2,9) = 4.51872	*
Mentha canadensis (Lamiaceae)	FSI		4.80 ± 6.33	20.05 ± 17.92	39.99 ± 18.56	F(2,9) = 5.26250	*
Mikania micrantha (Asteraceae)	NTU	Hex	24.11 ± 17.77	42.41 ± 16.78	47.40 ± 18.96	F(2,9) = 1.88617
		EtAc	9.11 ± 3.07	24.51 ± 9.76	26.18 ± 14.88	F(2,9) = 3.25933	•
Ocimum basilicum (Lamiaceae)	OIC		13.69 ± 8.32	27.93 ± 23.74	45.56 ± 18.24	F(2,12) = 3.95898	*
Pelargonium sp. (Geraniaceae)	FSI		15.79 ± 3.68	29.71 ± 11.95	49.89 ± 23.64	F(2,9) = 4.93377	*
Pittosporum pentandrum (Pittosporaceae)	TBG	Hex	19.38 ± 12.02	29.54 ± 4.77	39.71 ± 11.03	F(2,9) = 4.29317	*
		EtAc	13.54 ± 2.08	14.76 ± 11.67	31.72 ± 7.85	F(2,9) = 6.13291	*
Pogostemon cablin (Lamiaceae)	OIC		18.68 ± 20.35	28.22 ± 20.88	33.05 ± 20.14	F(2,15) = 0.76712
Salvia rosmarinus (Lamiaceae)	OIC		26.14 ± 21.82	45.62 ± 22.89	64.95 ± 18.53	F(2,9) = 3.36429	•
Santalum album (Santalaceae)	OIC		8.33 ± 10.64	24.63 ± 13.62	36.84 ± 17.83	F(2,9) = 3.98342	•
Setaria palmifolia (Poaceae)	TNF	Hex	46.36 ± 12.92	56.11 ± 12.95	57.78 ± 10.31	F(2,9) = 1.03635
		EtAc	33.35 ± 7.77	49.95 ± 18.96	49.51 ± 13.11	F(2,9) = 1.815
Syzygium aromaticum (Myrtaceae) bud	OIC		63.51 ± 8.38	60.75 ± 15.81	59.88 ± 18.15	F(2,8) = 0.06689
Syzygium aromaticum (Myrtaceae) leaf	OIC		47.05 ± 16.69	86.23 ± 7.24	92.84 ± 5.00	F(2,9) = 20.65571	***
Taiwania cryptomerioides (Cupressaceae)	TNF	Hex	26.03 ± 10.14	46.54 ± 16.02	54.82 ± 18.85	F(2,9) = 3.68589	•
		EtAc	34.52 ± 15.15	56.60 ± 5.24	56.78 ± 4.54	F(2,9) = 7.07732	*

Source abbreviations as in Table 1. Commercial oils were tested with ethanol as negative control. Means are of ≥ four independent Y-tube per application amount. % dec. = percentage of flies from the total that made a decision to leave the starting arm and enter the control or test arm. EtAc = Ethyl acetate. Hex = Hexane. SE = Standard error. Sig. =  Significance (p-values) of the ANOVA test comparing the three concentrations: • - p < 0.1 * - p < 0.05 ** - p < 0.01 *** - p < 0.001