Abstrakt

Effect of temperature on growth of Mastigocladus laminosus

Dr.A.C.Mongra

The Mastigocladus lamiosus has ability to fix carbon and nitrogen of atmosphere and due to this dual ability this can be explored further for algal biofertilizer in rice field where temperature remain above or around 45 0C in rainy season No growth of any of the thermal strains of cyanobacteria isolated from hot water spring Tattapani (HP) was obtained under laboratory conditions using spring water as nutrient medium. The maximum growth of Mastigocladus laminosus on the basis of chlorophyll-a concentration (4.2 μg chl-a/ml culture) after 15 days was obtained in Allen and Arnon's medium (pH 7.2) without nitrogen source at 45oC and cool fluorescent light (12 W/m2). Mass culturing of this species under laboratory conditions was done using laboratory fabricated fermentor for continuous use of the culture. The optimum growth with highest frequency of heterocyst (6%) of this strain was found at 45oC with an exponential phase upto 15 days. Significant decrease in the growth rate was observed at suboptimal temperatures of 25o and 35oC. This type of study is useful in exploring the possibility of use of thermal cyanobacteria Mastigocladus laminosus as biofertiliser in rice field