Safina Naz

Exploring the Potential of Quinoa Accessions for Salt Tolerance in Soilless Culture

Pakistan has more than 6 million hectares of salt affected land and quinoa is tested as a facultative halophyte having super food characteristics. A hydroponic study was conducted to explore salt tolerance of two quinoa accessions, Ames-13737 (Q7) and PI-634919 (Q9) under a range of NaCl levels (0, 100, 200 and 300 mM) in wirehouse during 2016. Plant nursery was raised, and at four leaf stage, the seedlings were transferred to plastic tubs containing 20 L half strength Hoagland’s solution as nutrient source. Salinity was developed incrementally to avoid osmotic shock after two days of transplanting. Results showed that growth (shoot length, root length and dry weight/plant) reduced drastically in Q9 by increasing the salinity level as compared to Q7. However, a comparable growth was observed in Q-7 at 0 and 100 mM i.e. the dry weight at 0 and 100 mM salinity were 0.8643 g and 0.8125 g, respectively. Furthermore, genotype Q7 was found better than Q9 by producing 10% more dry weight (0.2790 g) at the highest salinity level which was linked to 57% more leaf K accumulation (28.64 mg K g dry weight) as compared to Q9 (12.54 mg K g dry weight). It is concluded that tolerance of Q7 to salt stress might be due to more absorption of K by the roots at increased Na level.

Monitoring of Growth, Yield, Biomass and Heavy Metals Accumulation in Spinach Grown under Different Irrigation Sources

Growing of vegetables by the use of sewage water in peri-urban areas is a common practice which leads to heavy contamination of vegetables with metal ions. An experiment was conducted to compare the effect of canal, tube well and sewage water on growth, yield, biomass production and heavy metals accumulation in spinach. The heavy metals (Pb, Ni, Cu, Cd, Fe and Cr) contents in different water sources, soils and spinach plant parts grown with these irrigation sources were examined using atomic absorption spectrophotometer. The results declared that sewage water resulted in significantly greater growth, yield, biomass production and heavy metals contents compared with canal and tube well water and these metals contents were exceeding above the critical limits. Cu, Cd and Fe contents in sewage water irrigated soils were found above the maximum permissible limits, while Pb, Ni and Cr contents were within safer limits. Significantly greater heavy metals accumulation was recorded in edible parts of spinach grown with sewage water compared with canal and tube well water, which were exceeding the maximum permissible limits (MPLs). Canal water irrigated leaves samples also contained Cd and Fe above the permissible limits while all other metals contents were found within safe limits. The study concludes that regular examine of metals contents may possibly helpful in minimizing accumulation of these metals in the foods.