MSc

Oriculture involves the use of macrophytophagous oribatid mites to bring about biodegradation of plant litter, converting the same into nutrient rich humus which can be utilized as a bio-fertilizer.In oriculture, the oribatid mite species with a proven role in bio processing of plant litter are mass cultured and released into the soil. Success of oriculture lies in the right choice of oribatid mite species based on the particular type of plant litter. Oriculture can thus be treated as the modern method of agriculture with minimum cost of production and maximum yield in a most suitable ecofriendly atmosphere.
So the proposed study entitled “Decomposition of leaf litter by Oriculture” was conducted during the period 2014-2015 to envisage the standardization of the methodology for mass multiplication of selected oribatid mites, and to assess the degrading efficiency of soil dwelling oribatid mites on various types of leaf litter and also to evaluate the manurial value of bio processed litter.
Standardization of the methodology for oriculture based on the procedure suggested by Xavier and Haq (2006) was conducted in Completely Randomised Design with six treatments and three replications. For that soil samples were collected from different tree growing areas like cashew, rubber, jack, cocoa, teak and mixed forest plantation. Isolation of mites from soil and litter samples was carried out. It was not possible to extract mites from soil samples but isolation and mass culturing of mites using jack litter was made possible by using Berlese tulgren apparatus.
The potential of isolated mites to infest the crop plant okra was studied by releasing a known number of mites by adopting standard procedure. Since the mites being soil habituated, it could not survive on the plant. The isolation of symbiotic microflora associated with mites recorded fungal populations of 3×10-1 cfu/g of sample and bacterial population 11×10-1 cfu /g of sample. Among that most predominant microflora, four bacteria and
three fungi were selected for further studies, of which one belonged to Aspergillus sp. and other one was Penicillium sp. Invitro screening of symbiotic microflora for lignin,tannin,and cellulose degrading ability revealed that lignin and tannin degrading microorganisms were present. Antagonistic activity of isolated microflora against the five major soil borne pathogen revealed that the isolate bacteria 8 and fungi 3 can control all the tested one.
The experiment to assess the manurial value of decomposed litter was done by factorial CRD with different combinations of two factors, leaf litter of varying C:N ratio and different modes of biotic enrichment (Litter alone, litter+ cow dung , litter+ mites , litter+ cow dung+ mites ) as treatments and three replications. The percentage of litter decomposed was assessed and found that jack litter with the biotic enrichment litter+ mite + cow dung found to be the best combination showing the highest percentage irrespective of the litter type. Maximum percentage of litter decomposed was observed for jack litter with the biotic enrichment, litter+ cowdung+ mite and minimum decomposition rate was for cocoa with biotic enrichment litter alone.
Effect of different modes of biotic enrichments on the contents of macro and micro nutrients observed to be highest in the treatment combination litter + cow dung+ mites.Influence of litter types on nutrient content of decomposed litter revealed that highest carbon content (51.26 %) was in cashew litte, N content was in jack litter (3.20 %), P content (0.31 %) was in teak litter and highest K content (0.24%) in cocoa litter. Influence of litter type and biotic enrichment on N, P,K content of the decomposed litter showed that jack litter +cow dung +mites was highest in N content (3.46 %) and teak litter + cow dung +mites was highest in P (0.47 %) and mixed litter + cow dung + mites had highest K(0.21%) content.