The fungal biocontrol agent, Trichoderma harzianum, was evaluated for its potential to control the root-knot nematode Meloidogyne javanica. In greenhouse experiments, root galling was reduced and top fresh weight increased in nematode-infected tomatoes following soil pretreatment with Trichoderma peat-bran preparations. The use of a proteinase Prb1-transformed line (P-2) that contains multiple copies of this gene improved biocontrol activity in the greenhouse experiments compared with the nontransformed wild-type strain (WT). All the Trichoderma strains showed the ability to colonize M. javanica-separated eggs and second-stage juveniles (J2) in sterile in vitro assays, whereas P-2 also penetrated the egg masses. This protease-transformed line presented the same nematicidal and overall proteolytic activity as the WT in in vitro tests in which concentrated soil extracts from Trichoderma-treated soils immobilized the infective J2. However, the J2 immobilization and proteolytic activities of both P-2 and the WT were higher than those obtained with strain T-203. Characterization of the activity of all Trichoderma strains soil extracts on J2 showed that it was heat resistant and restricted to the low-molecular-weight fraction (less than 3 kDa). It is suggested that improved proteolytic activity of the antagonist may be important for the biological control of the nematodes.

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The fungus Trichoderma harzianum which was applied to pathogen-free soil, induced an increase in emergence of seedlings, plant height, leaf area and dry weight. The fungus was applied to the soil by three different methods: conidial suspension, wheat-bran/peat preparation and seed coating. The most prominent effect was observed in the wheat-bran/peat preparation. Responses occurred in different plant growth substrates such as sandy loam soil, autoclaved soil, vermiculite, peat and a mixture of vermiculite and peat (1 : 1, v/v). T. harzianum was also found in roots of plants growing in soil treated with the fungus.

Thickness of the lens, cortex and nucleus or nucleus with supranuclear layer, respectively, were determined for 58 controls aged 11-69 years (115 lenses), and for 175 patients aged 30-86 years with different types of cataract (247 lenses). Measurements of the densitograms of Scheimpflug photos (taken along the optical axis, magnified 10-fold) were performed, accurate to 0.5 mm (corresponding to 0.05 mm original size). The cataractous lenses were grouped in 5 morphological classes and 3 degrees of opacification (density according to the Scheimpflug photos). As regards normal lenses, the present authors' findings correspond to earlier findings of Niesel et al. (1976). Deviations from the normal pattern are found in typical cortical cataract (water-cleft and spokes cataract, wedge-shaped cataract) where nucleus and nucleus with supranuclear layer are thinner than the normal lenses, while with nuclear cataracts and mixed types the opposite is the case. In eyes with posterior cortical opacities no increase in the thickness of the anterior cortex is found with aging. With the true nuclear cataracts the increase in the thickness of the anterior cortex is negligible. The degree of opacification is closely related to an increase in the thickness of the nucleus and supranuclear layer, which implies a decrease in the thickness of the anterior cortex. Water-clefts and spokes of larger size cause the anterior cortex to become thinner. In eyes with wedge-shaped cataracts the different degrees of opacification did not affect the parameters measured.

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