Cashew (Anacardium occidentale) biotypes, nut forms and nut soaking effects on seedling emergence and growth

Abstract

A study was conducted to evaluate the effects of cashew (Anacardium occidentale L.) biotypes, nut forms and nut soaking in water on seedling emergence and growth. It was a 3×2×5 factorial experiment of 30 treatment combinations assigned in a randomized complete block design with four replicates. The factors were: cashew nut biotypes (madras, medium and extra-large); nut forms (sinkers and floaters in water) and duration of soaking (0, 6, 12, 18 and 24 h) before sowing. Parameters measured included percent sinkers and floaters; percent seedling emergence, seedling morphology and dry matter yield. Data were analyzed using descriptive statistics and ANOVA while means separation was done with DMRT. Percent sinkers:floaters ratios were significantly (p≤0.05) influenced by nut biotype. Ratios were 68:32, 88:12 and 14:86 in madras, medium and ex-large nut biotypes, respectively. Extra-large and medium nut biotypes had equal percent emergence which was significantly higher than for madras (75.0). Sinkers had similar percent emergence as floaters. Seedling height, stem diameter, leaf area and dry matter yield were in the order of extra-large nut biotype > medium > madras. Sinkers were significantly superior to floaters in seedling height and stem diameter, but similar in number of leaves and leaf area. Duration of soaking had no significant (p≤0.05) effect on the parameters measured. Interactions occurred between biotypes and nut forms. Conclusively, both sinker and floater nut forms of extra-large and medium nut biotypes could be sown, without soaking to obtain vigorous seedlings.