Improving the Productivity of Nigella sativa Plants Via Chitosan and Some Amino Acids

Seeds of Nigella sativa , are considered as one of the vital forms of available healing treatment. A field experiment was carried out to investigate the effect of chitosan (0.0, 1.0, 2.0, and 3.0 g/l) and two individual amino acids; glycine and tryptophan (0.0, 1.0, 2.0, and 3.0 g/l) application on plant growth and productivity. Results showed a significant effect of both investigated factors in herb day weight, seed yield, and proximate analysis. The highest seed yields (44.1 and 42.7 g/plant) with insignificant difference between them was for plants treated with 1.0 g/l of chitosan + (1 g/l tryptophan) or (3.0 g/l glycine) respectively. Whereas the minimum seed yield of about 21.2 and 21.7 g/plant was estimated for non-amino acid treated plants + 2.0 or 3.0 g/l of chitosan. The higher seed moisture content (5.37%) was for plants treated with 2 g/l of tryptophan in addition to 1.0 g/l of chitosan. Generally, increasing chitosan over 2.0 g/l caused a reduction in seed moisture content. Non-amino acid-treated plants that received 3.0 g/l of chitosan had the lowest ash (3.18%), but the highest value (4.63%) was for plants treated with 1.0 g/l chitosan + 1.0 g/l tryptophan. The lowest and highest lipids (28.11 and 30.75) were for untreated plants, and those treated with (2.0 g/l chitosan + 2.0 g/l tryptophan), respectively. Therefore, the study suggested that N. sativa plants could be treated with 1.0 g/l chitosan in addition to 1.0 g/l tryptophan to achieve the highest seed yield. However, for higher lipids content plants should be treated with 2.0 g/l of chitosan and 2.0 g/l tryptophan.