Germination and seedling establishment of dwarf-cashew (<i>Anacardium occidentale</i> L.) influence of salinity

Abstract

Seed germination and seedling establishment are crucial for maintaining the species in harsh conditions. Soil salinity affects germination and development of various plant species. The objective of this study was to evaluate the effects of salinity on germination, emergence and establishment of seedlings of dwarf-cashew. For this dispersion unit (fruit + seed) of clone CCP 76 dwarf-cashew were planted in plastic recipients containing vermiculite moistened with solutions of NaCl (0 and 50 mM), maintained under controlled conditions (40-80% relative humidity, 25 ± 2 °C, photoperiod 12 hours and light intensity of 300 ?mol m^-2 s^-1) for 24 days. The determinations carried out were: the curve of imbibitions, percentage of germination and emergence, seedling growth, mobilization of cotyledon reserves, and content of Na⁺ and K⁺ in the seedlings. Salinity delayed imbibitions, germination, emergence and seedling growth of dispersal units. While the excess of NaCl in the growth medium reduced the mobilization of cotyledon reserves and increased the accumulation of Na⁺ in the seedling parts and reduced the K⁺ content of roots. The osmotic and ionic component of salt stress seem to be responsible for inhibiting the depletion of cotyledonary reserves, and delayed growth and development of seedlings of dwarf-cashew.