Bacteria capable of detoxifying fusaric acid were isolated and tested for their ability to protect tomato plants from the wilting disease caused by Fusarium oxysporum f. sp. lycopersici Race 1. The bacteria used were fusaric acid-resistant mutants derived from an avirulent strain of Pseudomonas solanacearum. The capability of the bacteria to detoxify fusaric acid was assayed by incubating tomato callus cultures in filtrates of bacteria that had been grown in the presence of fusaric acid. Gas chromatography indicated that the detoxification of fusaric acid by the bacteria could be due to changes in the carboxyl group in the position alpha to the nitrogen of the compound. Fusaric acid detoxification was also demonstrated by protection of tomato leaf cuttings that had been treated with bacteria before treatment with fusaric acid. Intact tomato plants were protected from wilt when they were pretreated with fusaric acid-detoxifying bacteria before inoculation with the pathogenic fungus. These results suggest that fusaric acid is important in symptom development of wilting disease of tomato, and our approach shows promise for biocontrol.

Growth behaviour, plant vitality, nutrient content, yield production and carotenoid pigments in tomato cultivars, E-6203, UC-973 and VFN-8 was compared with the common adopted cultivars, peto 86 and Super Marmond. Cultivars response (growth and yield) to environmental local conditions did differ. Cultivar VFN-8 gave growth and yield than other tested cultivars. Cultivars treated with Alar gave an increase in early yield, total yield and yield components (Fruit number and fruit and fruit weight). External application of Alar to seedlings caused an appreciable increase in dry weight and vitality (chlorophyll retention test and cytokinin activity) as compared with the check. Seedlings treated with Alar contained more N, P, K and Mg than untreated control. Alar, also altered carotenoid pigments and soluble solids in tomato fruits. Tomato cultivars tested varied in their degree of response to Alar.

This research was conducted to perform biological studies on A.Solani; evaluate the susceptibility of some tomato cultivars to this disease; study the effect of enviromental condition in disease incidence; and finally the effectiveness of some fungicides on controlling the disease. Fifty isolates were obtained, some of these were capable to infect both stem and leaves, while others were able to attack leaves only.

Ten potato and 16 tomato cultivars were tested under field conditions for susceptibility to late blight caused by Phytophthora infestans (MONT) De Bary. The highest leaf infection index on potato was found on the cvs. Baraka and Spunta, whereas the cvs. Ajax and Origa were more resistant. The highest tuber infection percentages were found on the cvs. Baraka and Draga, while Ajax and Origa showed lower tuber infection percentages. The maximum leaf infection index in tomato was found on the cvs. Walter and Pacester-490, whereas the minimum was observed on Ace-55 vf and on Marmande-vf. The highest fruit infection percentage was noticed on the cvs. Walter and VFN-8 and the lowest fruit infection percentage was on Ace-55 vf and Marmande vf. The chemical control experiments on potato cv. Spunta and tomato cv. Ace-55 vf. showed that the fungicides polyram-combi, Dithane M45 and Tri-miltox-forte at the rate of 0.2%, 0.3% and 0.3% respectively, were effective in controlling the disease. The highest yield was recorded when polyram-combi was used

Screening of cucmber rhizosphere-soil under plastic-tunnels by dilution plates method, yielded 20 isolated of antagonistic bacteria which exhibited in vitro inhibitory action against Pythium ultimum Trow and Rhizoctonia solani Kuhn. Two isolates were identified as Bacillus spp. and were highly effective in controlling damping-off of cucumber and tomato seedlings caused by Pythium ultimum and Rhizoctonia solani, respectively, in the green-house conditions. Addition of the antagonistic isolate (SM 4) to sterile or nonsterile soil, at rate of 4g of bacterial peparation to one Kg of soil, resulted in 70% amd 58% surviving plants of cucumber comparing with 28% and 30%, in controls, respectively. In similar treatments the antagonistic isolate (SM 12) exhibited 80% and 82% surviving tomato plants compared with 30% and 32% in controls

The influence of inoculation of tomato plants with Glomus mosseae, a vesicular-arbuscular mycorrhizal fungus and phosphorus (P) nutrition on penetration, development, and reproduction of Meloidogyne incognita was studied in greenhouse. Results indicated that plants grown in high P soil had greater root weights, increased nematode penetration and egg production per plant, and increased colonization by mycorrhizal fungi, G. mosseae, compared with plants grown in low P level. VA mycorrhizae increased tomato fresh top and root weights, decreased nematode penetration and retarded reproduction. Mycorrhizal development and chlamydospore population produced on mycorrhizal-nematode infected roots were decreased, indicating the suppression of nematode on mycorrhizal plants. VA mycorrhizal fungus seemed to be more effective in reducing plant stress caused by nematodes, either the pre-infectional or post-infectional nematode-host relationship

Winter tomatoes are planted in unheated greenhouses at the beginning of October and harvested from January to May. They are attacked by various pests, which develop in summer on outdoor crops, enter the greenhouses through the ventilation openings, and attack the young plants. In autumn, the most severe damage is caused by the tomato yellow leaf curl virus (TYLCV), which is transmitted solely by the tobacco whitefly. Serpentine leaf-miners and aphids enter the greenhouses as well. The aphids transmit the potato virus Y (PVY). In November the pests' immigration ceases. During winter, the indoor pest activity is at its lowest due to the low temperatures. During March the tomato russet mite and the carmine spider mite start to reproce more intensively, and their populations build up rapidly. During this experiment, pest immigration and virus transmission were prevented by planting under a covering, which completely replaces chemical control and thus allows bio-organic farming. Positive airpressure in the greenhouses also reduced pest immigration. When pest immigration ceased, the cover was removed. Leaf-miners, when present, were usually controlled by naturally occurring parasites. The carmine spider mite was controlled by introducing predatory mites, and the tomato russet mite by dusting sulphur, which allowed biocontrol.

Field grown bare root tomato transplants packed in commercial shipping crates were precooled in a batch type precooler by forced air cooled with liquid carbon dioxide (L-C02). The precooled transplants were shipped via commercial truck from Tifton, GA to Fremont, OH. Some of the precooled and nonprecooled transplants were immediately planted in the field upon reaching destination and some were planted after 5 days of storage either at ambient or at 7°C temperatures. The technique of precooling using L-C02 was successful but there was nonuniform cooling between crates. The precooled transplants went through a heating and cooling cycle in transit because of the heat load of nonprecooled transplants. The survival and fruit yield data indicated that the performance of precooled and nonprecooled transplants was similar when they were not stored. The performance of stored transplants was worse than unstored transplants and the performance of precooled-stored transplants was worse than nonprecooled-stored transplants. Successive heating and cooling of precooled tomato transplants caused damage.

Fourteen race-1 and race-2 isolates of Verticillium dahliae from North America, Europe and Australia were screened against the near isogenic pair of tomato cultivars Roma and Roma VF. The foliar symptoms, extent of stunting and vascular colonization were assessed. Race-1 isolates were significantly more pathogenic on Roma which lacks the Ve resistance gene. Race-2 isolates from N. Amercia were more pathogenic than those from Australia. All isolates tested colonized both cultivars to some extent although the level of colonization by race-1 isolates was significantly higher in Roma than in Roma VF. All race-1, and the majority of race-2, isolates caused stunting of Roma. No isolates stunted Roma VF