Cytological changes and some postharvest quality traits of leeks grown in soil incorporated with partially burnt rice hull as a low-cost silicon source
Postharvest quality and some cytological changes were investigated in leeks (Allium porrum 'Jambo') grown in fields supplemented with silicon. Three different treatments were applied by incorporating different ratios of partially burnt rice hull (PBRH) into leeks beds: 0 kg m‑2 bed (T0), 1 kg m‑2 bed (T1) or 2 kg m‑2 bed (T2). Treatments were composed of nine beds with three replicates each, arranged in a randomized complete block design. Some postharvest qualities such as rate of leaf yellowing, percentage weight loss, marketable yield and chlorophyll retention, were determined in both partially burnt rice hull treated or non-treated control leeks stored at room temperature (30°C) or cold storage at 10°C. The percentage weight loss was reduced in cold stored silicon treated leeks while maintaining the marketable weight of the product. The rate of leaf yellowing was reduced in both stored at room temperature (30°C) or cold storage at 10°C and extended the shelf life by two days compared to untreated control. Soil-plant analyses development (SPAD) measurements indicated significantly higher levels of chlorophyll retention in partially burnt rice hull treated leaves. The mechanism underlying the improved postharvest quality of leeks was investigated by observing the cytological alterations in treated leaves through light microscopy and scanning electron microscope (SEM). Significantly higher cuticle thickness was observed in PBRH treated leaves. The SEM studies revealed the presence of silicon depositions in leaf cuticle and stomata and improvements in cellular structural rigidity of PBRH treated leeks.
Weerahewa, H.L.D. and Rajapakse, R.P.S.S. (2020). Cytological changes and some postharvest quality traits of leeks grown in soil incorporated with partially burnt rice hull as a low-cost silicon source. Acta Hortic. 1278, 29-38
leaf yellowing, weight loss, chlorophyll retention, cuticle thickness, shelf life