Occupational Health & Safety

Biography

Biography: T.V. Rajya Lakshmi

Abstract

UAE soils are about 80% sandy and highly infertile containing high amounts of salt. Only salt tolerant/ resistant crops like date palm and ghaf tree grow in these salt affected soils. To expand cultivation of crops in such soils, the soils need to be enriched with chemical or organic fertilizers. Two experiments were carried with Chlorella vulgaris and C. pyrenoidosa: In experiment I the cells of both the species were cultured in different culture conditions and in experiment II the cells were used as biofertilizer to germinate and grow lettuce, cucumber, coriander and eggplant seedlings up to one month. The nutritional requirements and growth conditions of the two species were different: Chlorella vulgaris was heat sensitive and salt tolerant, (up to 0.1% NaCl), grew best in Chu 10 nutrient medium, while C. pyrenoidosa is salt sensitive, and heat tolerant (up to 40ºC) grew better in Bold’s basal medium, both maintained at 16h/8h light/dark photo period. When Chlorella pyrenoidosa live cells (11.8x104/ml) is used as biofertilizer, 97% of cucumber seeds germinated against 80% in controls while lettuce tolerated water deficit up to 7 days. Similar results were obtained in coriander when irrigated with C. vulgaris cells. One month old seedlings irrigated with either biofertilizer were with greener leaves and 1.5 to 2 times higher chlorophyll “a” and “b” content compared to the respective control plants among all the crops. The photosynthetic green alga Chlorella species seems to be a promising biofertilizer for these vegetable crops to be grown in the UAE soils.