Evaluating the Establishment and Agronomic Proficiency of Cyanobacterial Consortia as Organic Options in Wheat–rice Cropping Sequence

Abstract

Cyanobacteria represent promising organic inputs in rice-wheat cropping system, as they contribute towards accretion of N and C, besides secreting growth-promoting substances which influence plant productivity and soil fertility. The present study focused towards using a combinatorial approach for evaluating field-level colonization of cyanobacteria in soil and their effect on soil microbiological and plant parameters, employing agronomic and molecular tools. A consortium of cyanobacterial strains (BF1, Anabaena sp., BF2, Nostoc sp., BF3, Nostoc sp. and BF4, Anabaena sp.) was employed in different three-and four-member combinations along with 75% N + Full dose of P and K fertilizers. A significant enhancement in microbial activity and plant growth/yields and savings of 25% N in the wheat-rice cropping sequence were recorded, especially in treatments involving 75% N + Full dose of PK+BF1+BF2+BF4 and T5, i.e. 75% N + Full dose of PK+BF1+BF2+BF3. Such treatments were significantly higher or statistically at par with fertilizer controls -75% N + Full dose of PK fertilizers. The use of DNA-based markers further helped to establish the colonization of the inoculated cyanobacteria, especially BF2 and BF3 strains. Our study clearly illustrated the establishment of inoculated cyanobacterial strains and their role in enhancing the crop productivity and soil health of the rice-wheat cropping system.

Productivity of mungbean (Vigna radiata) with elevated carbon dioxide at various phosphorus levels and cyanobacteria inoculation

“…Cyanobacteria play an important role under elevated CO 2 condition as it has photosynthetic mechanism that is similar to eukaryotic algae and plant. Application of cyanobacteria in crops like rice, wheat, tomato, soybean, pulse and vegetable crops is well documented (Kaushik and Venkataraman, 1979;Karthikeyan et al, 2007;Prasanna et al, 2013). But this area has not been adequately studied except for rice in improving their biofertilizing potential in agriculture.…”

Association of N2-fixing cyanobacteria with wheat (Triticum vulgare L.) roots

“…strain 2S9B could easily co-exist within wheat tissue, making it a promising organism for achieving a biological association between a N 2 -fixing bacterium and wheat. Gantar and Elhai (1999) and Prasanna et al (2013b) tested four heterocystous cyanobacteria, belonging to the genera, Anabaena and Nostoc for their ability to form associations with the roots of wheat seedlings under using hydroponics. The cyanobacterial strains formed close associations with wheat plants, and were able to enter through root hairs and penetrate the epidermal layer of wheat roots.…”

“…In the recent years, several attentions have been drawn to use cyanobacterium that exists in the different soils as a biofertilizer for its capability for N 2 -fixation and organic compounds assimilation (Prasanna et al, 2004). Efficiency of cyanobacteria to form such successful beneficial collaboration by invading the plant roots is of a considerable agronomic importance, particularly for cereal production (Singh et al, 2011;Prasanna et al, 2013b). Likewise, some of cyanobacteria showed an effective role in stimulating soil fertility by producing plant growth enhancing substances, consequently increasing nutrients availability and plant uptake (Sergeeva et al, 2002;Prasanna and Kaushik (2006).…”

Prospecting cyanobacterial formulations as plant-growth-promoting agents for maize hybrids

“…Biological nitrogen (N) fixation through cyanobacteria contributes 25-30 kg N ha −1 per cropping season and may increase rice yields by 10-15% (Venkataraman 1972;Mandal et al 1999). Cyanobacterial consortia, and more recently biofilmed preparations using agriculturally important rhizospheric bacteria and fungi, have shown promise as plant-growth-promoting inoculants/biocontrol agents in a diverse range of crops, such as wheat, cotton, legumes, spices and vegetables (Karthikeyan et al 2007;Nain et al 2010;Manjunath et al 2011;Chaudhary et al 2012;Prasanna et al 2012;Rana et al 2012;Prasanna et al 2013aPrasanna et al , 2013bPrasanna et al , 2013cKumar et al 2013;Prasanna et al 2014Prasanna et al , 2015. However, the effect of different cyanobacterial inoculant combinations on the growth of popular maize hybrids has not been investigated.…”

“…(PW5), Azotobacter chroococcum (W5), Anabaena sp. (CW1) and a set of four cyanobacterial strains -Anabaena torulosa BF1, Nostoc carneum BF2, Nostoc piscinale BF3 and Anabaena doliolum BF4 (Prasanna et al 2009(Prasanna et al , 2013b) -were obtained from the germplasm collection of the Division of Microbiology, Indian Agricultural Research Institute (IARI), New Delhi, India. Trichoderma viride (ITCC 2211) was obtained from the Indian Type Culture Collection (ITCC), Division of Plant Pathology, IARI, New Delhi, India.…”