Salinity influences plant growth, seed yield and seed quality even of halophytic crops such as Chenopodium quinoa. Plant growth, total seed yield, number of seeds, fresh weight and dry weight of seeds, were all significantly reduced in the presence of salinity. Only at high salinity did the content of proteins (as well as total N) increase significantly in the seeds whereas the content of total carbohydrates (as well as total C) decrease. Aside from that the capacity for germination was diminished by a reduced seed size and a disproportionate reduction of the volume of the perisperm. However, the reduced capacity seemed to be compensated by an accelerated germination owing to high Na and Cl concentrations leading to a low water potential in the walls of the plant ovary. At high salinity the passage of NaCl to the seed interior was hindered by the seed cover. There was an obvious gradient between potentially toxic (Na and Cl) and essentially needed elements (K, Mg, Ca, P and S) across the seed coat of salt treated plants and also a significant change of the distribution of elements in the embryo. The results indicate a highly protected seed interior leading to a high salinity resistance of quinoa seeds.

A prerequisite for sustainable saline agriculture of cash crop halophytes in salt affected areas implies exact knowledge of their limits of salinity resistance. Hence, the first part of this study was carried out in pot experiment under greenhouse conditions to evaluate growth and seed yield of C. quinoa Willd. cv. Hualhuas to varying water salinity levels (0, 100, 200, 300, 400 and 500 mM NaCl). The limit of salinity resistance was estimated at 200 mM NaCl (~20 dSm -1 ) based on seed yield production. Depending on the results obtained from pot experiment, field trials were conducted in saline soil location (ECe 17.9 dSm -1 ) and in non-saline soil location (ECe 1.9 dSm -1 ). Seed yield significantly decreased under saline soil by about 61.7% . Beside quantity, soil salinity led to reduce the percentage of moisture, total carbohydrate and total fat contents in seeds. Salinity did not significantly alter the protein content in quinoa seeds. Significant increases in the content of ash and fiber were detected in response to high soil salinity. The high er ash content in seeds under saline conditions was due to the increase of Na + as well as K + , P 3-and Fe ++ concentrations. By contrast, soil salinity led to significant decrease of Ca ++ and Zn ++ contents in seed. Energy dispersive X-ray microanalysis showed that most of Na + in the seeds produced at saline soil was mainly accumulated in the pericarp followed by embryo tissues, while, the interior reserving tissue (perisperm) exhibiting comparatively low concentration. Increasing most of essential minerals, especially Fe, in quino a seeds produced under high saline conditions given quinoa a distinctive value for human consumption. Quinoa can be grown and yielded successfully in salt-affected soils (ECe 17.9 dSm -1 ), where, most if not all of traditional crops cannot grow, although the yield was reduced however, the seed quality was not highly affected.

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A major limiting factor for quinoa cultivation as a grain crop on a large scale are virus diseases, in particularly seed borne diseases. Therefore, a somatic embryogenesis protocol is a necessary tool to produce virus free plants. Somatic embryogenesis offers the possibility of mass production of transgenic plants and therefore can be used easily to study the effect on plants resulting from breeding processes. An in vitro protocol has been developed for somatic embryogensis from calluses and cell cultures of Chenopodium quinoa. Callus was induced from hypocotyl explants within 2 weeks of culture on a modified Murashige and Skoog (MS) medium supplemented with 0.45 lM 2,4-D D . Calluses were cultured on solid or liquid MS medium and later the development of somatic embryos was observed on both employing the same MS medium without 2,4-D D . To our knowledge this is the first report of somatic embryogenesis in Chenopodium quinoa.