Plants harbor endophytes, capable of producing metabolites and enzymes with functions similar to host plant extracts. An inventory of Lantana camara's endophytes could better explain the role played by extracts of this plant in its defense functions against pathogens. This study aimed at isolating and screening endophytic fungi from L. camara leaves for amylases, lipases and laccases production and for the production of some secondary metabolites using standard procedures. In-vitro culture techniques with Potato Dextrose Agar (PDA) as culture medium were used to isolate endophytes from L. camara leaf tissues. Isolates identification were done using macroscopic and microscopic characteristics. Three endopyhtic fungi were isolated and labeled LI, LII, and LIII; LI and LII had a slimy texture and produced no reproductive structures (spores, conidia, septate hyphae etc) hence identified as mycelia sterilia. LIII was white, with an uneven surface growth, cottony dry aerial mycelium, visible hyphae with little branching and individual hyphae were septate, hence a Geotrichium sp. All isolates produced amylases and lipases while LIII solely produced laccase. The extract of LIII showed the presence of tannins and cardiac glycosides and absence of phenols and saponnins. The anti pathogenic roles of L. camara extract are thanks to the presence of endophytes in its tissues which produce enzymes that mediate plant defense functions as well as secondary metabolites with anti-pathogenic properties.

A field experiment was conducted in Bambili, North West Region of Cameroon to evaluate the morphological and agronomic parameters of potato grown in soil treated with two organic manures as well as soil physico-chemical properties. A randomized complete block design (RCBD) with three treatments (EM manure, IMO manure and control), and four replications was conducted. Results showed significant differences (P ≤ 0.05) in the height of plants and leaf area index throughout the period of experiment in plants treated with both manures. IMO manure produced taller plants (65.150 ± 17.850 cm) compared to EM manure (57.642 ± 12.146 cm) and the control plants (19.070 ± 4.215 cm). The highest leaf area index was recorded by plants treated with IMO manure followed by those treated with EM manure, and then the control. The fresh weight of tubers produced by IMO manured plants (241.64 ± 32.94 g) was higher than those of EM manured plants (227.62 ± 44.58 g), and control (125.66 ± 31.63 g). Both IMO and EM manures had significant positive effects on soil physico-chemical properties, morphological parameters, and yields. However, IMO manure had better effects. Soil physico-chemical properties revealed a decrease in electrical conductivity, total phosphorus, calcium content and magnesium content. IMO treated soil recorded the higher rate of decrease, followed by EM treated soil and control soil, total organic carbon increased while total nitrogen content did not change during experiment for manure soils.

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Colocasiae esculenta is an important tropical tuber crop susceptible to attack by many diseases. The most devastative among these is Taro leaf blight cause by the pathogen Phytophthora colocasiae. The pathogen can cause rapid complete defoliation and crop destruction and under some circumstances, the disease can attack harvested corms and cause heavy losses during storage. Endophytes constitute an important source of bioactive secondary metabolites and enzymes. Based on their phytochemical properties, they can be used as a source of antifungal agent for the treatment of some infectious diseases. In order to evaluate the impact of endophytes on plant defence, in vitro evaluation of the growth effect of endophytic fungi against P. colocasiae was conducted in dual culture, after isolating and screening endophytic fungi from L. camara leaves for their production of some extracellular enzymes (amylases, lipases, laccases, protease and cellulose) and some secondary metabolites (tannins, saponins, phenols, cardiac glycoside) using standard procedures. In-vitro culture techniques with Potato Dextrose Agar (PDA) as culture medium were used to isolate endophytes from L. camara leaf tissues. Isolate identification was done using macroscopic and microscopic characteristics. These isolates were then tested in vitro to evaluate their morphological growth effect against P. colocasiae via the dual culture. Five endophytic fungi were isolated from Lantana camara leaves and coded L 1 , L 2 , L 3 , L 4 and L 5. The L 2 , L 3 and L 5 strains were filamentous and showed coenocytic hyphae which bore some structures' called conidiosphores identified as Cladosporium sp. L 1 strain was filamentous fungi having clamp connections hyphae (bridge-like growth) above hyphal septa and brown sclerotia. L 4 strain showed very tiny interwoven and tightly parked mycelia. As enzyme activities, all the strains were found to produce amylase and not protease. L 1 , L 3 and L 4 were able to synthesis laccase while L 5 produced cellulose and lipase. For the secondary metabolites, all the strains were able to produced tannins and cardiac glycoside but they did not synthesis saponins. L 1 , L 2 and L 4 strains were able to produced phenol. In dual culture, the growth of the pathogen decreased the growth rate of the endophytes. L 2 strain grew normally by forming an arc around P. colocasiae growth while L 3 and L 5 strains induced the pathogen to grow on the opposite side of P. colocasiae. Concerning L 1 and L 4 strains, there were no effect. Based on the antifungal activities against P colocasiae, these strains L 2 and L 3 could be used for biological control of taro life blight.