GERMINATION OF CACTUS SEEDS UNDER SALINE STRESS

SILVA, JOÃO HENRIQUE CONSTANTINO SALES; AZERÊDO, GILVANEIDE ALVES DE

doi:10.1590/1983-21252022v35n108rc

Acessibilidade / Reportar erro

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

Agronomy • Rev. Caatinga 35 (01) • Jan-Mar 2022 • https://doi.org/10.1590/1983-21252022v35n108rc copy

GERMINATION OF CACTUS SEEDS UNDER SALINE STRESS

GERMINAÇÃO DE SEMENTES DE CACTÁCEAS SOB ESTRESSE SALINO

Authorship SCIMAGO INSTITUTIONS RANKINGS

ABSTRACT

Cactus seeds in seasonal dry tropical forests are subject to several stressors, such as salt stress which limits imbibition and therefore germination. Thus, this study aimed to compare germination performance of Cereus jamacaru subsp. jamacaru and Pilosocereus pachycladus subsp. pernambucoensis seeds under salinity conditions. To this end, NaCl and KCl solutions were used in the following osmotic potentials: 0.0 (control),-0.2,-0.4,-0.6,-0.8,-1.0, and-1.2 MPa. Seeds were placed to germinate at 25 °C and 12-hour photoperiod. The number of germinated seeds was counted daily for 21 days after root protrusion. The variables analyzed were: water content, germination, normal seedlings, germination speed index, and average germination time. The experimental design was completely randomized, following a 2 × 7 factorial scheme (species × osmotic potential) for each saline source. Water restriction and ionic effect caused by salts favored seed germination and vigor in both species at-0.2 and-0.4 MPa. However, from-0.8 MPa onwards, germination decreased significantly for both salts. Seeds of C. jamacaru subsp. jamacaru and P. pachycladus subsp. pernambucoensis were tolerant to salt stress since they germinated up to-0.8 MPa (NaCl) and-1.2 MPa (KCl). The latter occurred only for P. pachycladus subsp. pernambucoensis.

Keywords:
Caatinga; Cereus jamacaru ; Pilosocereus pachycladus ; Salinity; Vigor

Area	Coordinates	Altitude (m)	Annual average temperature (min-max; °C)	Annual average rainfall (mm)	Soil	Taxon
Campina Grande, PB	7°13'50"S 35°52'52"W	546	23.5 (28.8- 20.2)	777	Litholic Neosol	C. jamacaru subsp. jamacaru
Bananeiras, PB	06º45'00"S 35º37'00"W	552	22.3 (27.8-18.8)	1.188	Red-yellow Oxisol	P. pachycladus subsp. pernambucoensis

Sources of variation	DF		Mean squares
Sources of variation	DF	G	NS	GSI	MGT
		NaCl
Species (S)	1	193.1429^ ,* significant at 1% and 5% probability by the F-test, respectively.	236.1607^ ,* significant at 1% and 5% probability by the F-test, respectively.	38.4457^ ,* significant at 1% and 5% probability by the F-test, respectively.	3.2064^* **,* significant at 1% and 5% probability by the F-test, respectively.
Osmotic potential (Op)	6	16001.4762^ ,* significant at 1% and 5% probability by the F-test, respectively.	5958.6131^ ,* significant at 1% and 5% probability by the F-test, respectively.	214.7845^ ,* significant at 1% and 5% probability by the F-test, respectively.	59.4304^ ,* significant at 1% and 5% probability by the F-test, respectively.
S × Op	6	272.1429^ ,* significant at 1% and 5% probability by the F-test, respectively.	301.9940^ ,* significant at 1% and 5% probability by the F-test, respectively.	11.7607^ ,* significant at 1% and 5% probability by the F-test, respectively.	85.1227^ ,* significant at 1% and 5% probability by the F-test, respectively.
Residue	42	6.7619	20.4464	0.7981	0.6051
Average		65.3571	38.3393	6.9571	5.2000
CV (%)		3.97	11.79	12.84	14.95
		KCl
Species (S)	1	19.4464^ns ns - non-significant.	391.1429^ ,* significant at 1% and 5% probability by the F-test, respectively.	0.5111^ns ns - non-significant.	181.0802^ ,* significant at 1% and 5% probability by the F-test, respectively.
Osmotic potential (Op)	6	13526.5774^ ,* significant at 1% and 5% probability by the F-test, respectively.	4744.9048^ ,* significant at 1% and 5% probability by the F-test, respectively.	262.4309^ ,* significant at 1% and 5% probability by the F-test, respectively.	38.9956^ ,* significant at 1% and 5% probability by the F-test, respectively.
S × Op	6	260.8631^ ,* significant at 1% and 5% probability by the F-test, respectively.	397.4762^ ,* significant at 1% and 5% probability by the F-test, respectively.	6.7974^ ,* significant at 1% and 5% probability by the F-test, respectively.	103.9698^ ,* significant at 1% and 5% probability by the F-test, respectively.
Residue	42	7.0893	22.9524	0.6549	0.8888
Average		68.3036	40.2857	7.3795	6.2518
CV (%)		3.89	11.89	10.96	15.07

Universidade Federal Rural do Semi-Árido Avenida Francisco Mota, número 572, Bairro Presidente Costa e Silva, Cep: 5962-5900, Telefone: 55 (84) 3317-8297 - Mossoró - RN - Brazil
E-mail: caatinga@ufersa.edu.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] *Corresponding author