EFFECT OF SALINITY ON GROWTH AND LEAF YIELD OF SPIDERPLANT (Cleome Gynandra L.)

Abstract

This study was conducted to investigate the effect of salinity (NaCl) on growth and leaf yield of spiderplant. The experiment was laid out in a completely randomized design (CRD) with four replicates. Seeds of spiderplant ( Cleome gynandraL.) were sown in soil-filled 20-liter plastic pots. The pots were irrigated with tap water for up to four weeks after germination. The plants were then subjected to five levels of salinity by irrigating the pots daily with salt solutions of concentrations: 0 mol / kg (control), 0.07 mol / kg, 0.13 mol / kg, 0.20 mol / kg and 0.26 mol / kg. These solutions were made to exert osmotic potentials of 0 MPa (control), -0.3 MPa, -0.6 MPa, -0.9 MPa and -1.2 MPa, respectively, in the rooting medium. Data on leaf and general plant growth parameters were collected weekly, including fresh and oven-dried weight of the leaves, chlorophyll content, leaf number, leaf weight ratio, root / shoot ratio and days to 50% flowering. Results show that salinity significantly decreased general plant growth, leaf chlorophyll content, leaf growth and yield, and retarded flower development. This indicates that spiderplant has a poor capacity for regulating the entry, translocation and compartmentalization of salt. This allows large amounts of salt to be absorbed and translocated to the shoots and leaves, where they either retard or inhibit cell division and expansion, and reduce photosynthetic rates as well as increasing respiration rates. Observed root death was attributed to indirect effect due to the deterioration of soil structure in the presence of high concentrations of sodium ions. However, it was also observed that the species can survive and continue to grow under conditions of moderate salt stress. Salt stress of -0. 3 MPa does not affect the growth of this species and the species can survive, grow and reproduce when exposed to a salt stress of up to -0.9 MPa, albeit at retarded rates, due to the species \ 'capacity for osmotic adjustment. It is concluded that although spiderplant is salt-sensitive, its observed capacity for osmotic adjustment is a promising trait, which through further investigation, may form a criterion in the selection and breeding of salt-resistant cultivars of spiderplant.