Two series of experiments were employed in evaluating integrated pest management for the control of root knot nematodes in tea. The first series involved evaluation of several control options involving intercropping tea with marigolds (Tagetes minuta), and the use of a nematicide Furadan 1 5G and potash fertilizer. The severity of knotting was reduced in treatments with Furadan 1 5G, T. minuta and potash by 28.7, 24.3 and 44%, respectively, over the 2-year study period. The T. minuta intercrop, however, retarded tea development. The second series of experiments involved screening for host plant resistance using 8, 24 and 25 cultivars at each of three different sites. The cultivars displayed significant variation in resistance to root knot nematode infection; several were resistant, a few moderately tolerant, while others were susceptible. Generally, progenies of susceptible and resistant cultivars exhibited similar phenotypes to their progenitors, indicating apparent susceptibility and resistance, to be highly heritable traits. The study demonstrated that the use of nematode-resistant cultivars is clearly the most practicable, environmentally friendly and cost-effective option for controlling nematodes in tea, although augmenting host-plant resistance with potash fertilizer could give better results.

Plant parasitic nematodes, whose control options are restricted, continue to cause enormous losses in crop production systems including carnations. This study was carried out with the aim of developing environmentally sound approaches for adoption in the management of phytonematodes affecting carnations. Various organic amendments were evaluated namely sugarcane bagasse, tea and assorted flower composts and molasses, in addition nematophagous fungus Paecilomyces lilacinus (PL plus ® ) and neem (Achook ® ). Meanwhile, a standard chemical nematicide, fenamiphos (Nemacur ® ), was used next to untreated plots were as control. The experiments were carried out under greenhouse conditions. Soil samples were collected before application of the amendments and at 90 and 180 days after treatment. Parasitic nematodes belonging to 16 genera were detected in plots where carnation had been produced under monoculture over several years. The most predominant of the nematodes detected were in the genera Scutellonema, Helicotylenchus and Meloidogyne, with 100, 82 and 100% frequencies of occurrence, respectively. Treatments effects caused a reduction in numbers of plant parasitic nematodes, with the exception of nematodes in the genera Helicotylenchus, Criconema and Longidorus. Galling due to root-knot nematode was reduced by between 53%, in plots treated with sugarcane bagasse, and 69% in those treated with neem. This study has established that application of organic substrates, neem and P. lilacinus reduced plant parasitic nematodes. The materials can be recommended for use in sustainable carnation production systems.

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Epiphytes are a group of non-parasitic plants that settle to obtain support from plants. Under the natural forest ecosystem, the presence of epiphytes is an indicator of unpolluted and undisturbed environment. However, massive infestation by epiphytes to commercial tree crops including tea is a concern to productivity. A study was conducted initiated to determine the influence of different management options on epiphytes which included mosses, ferns, maidenhair ferns, and tongue ferns. The study evaluated the influence of different management options on epiphytes and to determine the effect of the management options on tea yields. The experiment was laid on a field infested with epiphytes in split plot design treatment structure in a randomized complete block layout, replicated three times. In the main plots the epiphytes were manually removed from the tea bush branches whereas the control was left in situ while the subplots involved use of agricultural chemicals; Copper Nordox, Cuprocaffaro, Milraz, Hydrate of lime, Round up Turbo and control (untreated). Post-treatment scoring for 3 years of all types of epiphytes was done using a scale to determine the level of yellowing, scorching, and regrowth. Yield data were also recorded for one prune cycle of four years and data was subjected to analysis of variance. The main treatments (disturbed and undisturbed) management options did not influence the efficacy of the chemical products on epiphytic mosses but disturbance reduced (p less than or equal to0.05) levels of the epiphytic ferns. Copperbased products (Copper Nordox and Cuprocaffaro) reduced (p less than or equal to0.05) in mosses levels (reducing the degree of yellowing and regrowth) than other products and the control. However, all chemical products reduced (p less than or equal to 0.05) levels of epiphytic ferns. The removal of epiphytes on the tea branches increased (p less than or equal to0.05) the yield of tea, while chemical products were ineffective in improving yields. This study, therefore, concludes that the epiphytes on the tea frame have effects on the functioning of the tea bush and removal of the massive epiphytes is necessary for improved productivity of tea bush.