2Department of Microbiology, Punjab Agricultural University, Ludhiana-141004.
Department of Animal Nutrition, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana-141004, (Punjab), India
1 Corresponding author bakshimps@yahoo.com;
Nutritional value of wheat straw inoculated with blend of lignolytic fungi was assessed. The moistened wheat straw in batches of 500 g (DM basis) was inoculated with the wheat grain spawn of Pycnoporus sanguineus (PC) mixed either with Oideodendron echinula (OE), Trametes lirsuta (T) or Phialophora hoffmannii (PHL) in 50:50 ratios @ 5%. Spawned straw filled in perforated polyethylene bags was incubated at 30°C till the appearance of fruiting bodies. The release of sugars and pentoses, irrespective of incubation period, was highest (P<0.01) in PC-T, followed by PC-PHL and lowest in PC-OE combination. The PC-T combination was highly lignolytic as indicated by highest (P<0.05) release of phenolics as compared to PC-OE, in which the release of phenolics was lowest. Irrespective of fungal strain combination, the release of soluble sugars, pentoses and phenolics increased (P<0.01) linearly with the increase in incubation period. Amongst the fungal combinations, PC-OE utilized minimum nutrients from the substrate (wheat straw) for their proliferation. The in-sacco DM degradability (irrespective of the incubation period) was highest (P<0.01) in PC-OE inoculated straw as compared to PC-T and lowest in PC-PHL. However, the NDF degradability was highest (P<0.01) in PC-T followed by PC-OE and lowest in PC-PPIL. The DM degradability increased (P<0.01) up to 3rd day, while NDF degradability increased (P<0.01) linearly up to 6th day of incubation, thereafter the degradability of both DM and NDF declined gradually. The DM utilization/loss, irrespective of incubation period, was highest (P<0.01) in wheat straw inoculated with PC-T followed by PC-PHL and lowest in PC-OE. The enrichment of straw with protein was highest (P<0.01) in straw incubated with PC-T as compared to PC-PHL combination. The protein enrichment was comparable in PC-T and PC-OE inoculated straw. The true protein content and the DM utilization, irrespective of fungal combinations, increased (P<0.01) linearly with the increase in incubation period. The results revealed that by combining different fungal strains synergistic response on lignin biodegradation and enrichment of straw with microbial protein could be achieved. The combination of PC-OE was considered to be the best for improving the nutritive value of wheat straw.
Biodegradation, In-sacco degradability, Blend of lignolytic fungi
