Abstract
Widely cultivated in the Asian regions, Azolla is either incorporated into the soil before rice transplanting or grown as a dual crop along with rice. To examine the feasibility of its use in flooded rice fields, the study was conducted during 2011-13 with 9 different species/ strains of Azolla at BAU Sabour, to study the growth-development dynamics and the resistance/tolerance to extreme temperature which generally occurs in the area. Azolla biomass increased during February- April but suddenly decreased during May-June and again increased during July-September thereafter, biomass decreased during October-January. The correlation coefficient between biomass growth rate of strains A. faliculoides, A. microphylla and BAUAS-1 of Azolla and maximum temperature was found significantly positive. Significant positive correlation between biomass production of species A. faliculoides and strain BAUAS-1 with minimum temperature was found 0.70 and 0.62 respectively, which indicates that increase in minimum temperature up to limit, may increase the growth rate in these strain/spp. There was significant negative correlation (0.70, 0.63 and 0.68) between biomass production rate and relative humidity measured at morning, in the species/strain A. rubra, BAUAS-1, BAUAS-2 respectively. Biomass production rate of azolla species A. pinnata showed significant negative correlation with relative humidity at evening. Significant positive correlation between biomass production and rainfall during the growth period in species A. faliculoides was found, which indicates rainfall or sufficient water increases the growth in Azolla.
Highlights
The aquatic pteridophyte, Azolla is an excellent biofertilizer and green manure having global distribution
Increase in the growth rate measurements are important in the estimation of the amount of Azolla required to inoculate rice paddies and to provide a sufficient nitrogen contribution (25–30 kg ha-1)
Azolla biomass increased during February- April but suddenly decreased during May-June and again increased during July-September thereafter biomass decreased during October-January (Table 2)
Summary
The aquatic pteridophyte, Azolla is an excellent biofertilizer and green manure having global distribution. (Lumpkin and Bartholomew, 1986) and it was in the range of 65-75% based on the study of Biswas et al, (2005) in Indian condition According to the latter authors, for optimum Azolla growth and biomass production, high temperature, high humidity and low water depth may not be good conditions in particular during the dryseason. In order to make use of the Azolla fern as a practicable Biofertilizer in rice fields in India , research is required for identifying fern strains with good resistance to high summer temperature and to alternating day/night temperatures before the rice sowing period, and to be able to produce the needed. The study was carried out aimed at comparing different Azolla strains, analysing the growth rate of their biomass before the sowing of rice to evaluate it as rice Biofertilizer
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
