It was tried to determine the correlation between the intensification of symptoms of tomato wilt disease caused by the fungus Verticillium dahliae, and the presence of nematode Meloidogyne hapla. It was ascertained that the nematodes clearly accelerate infection and shorten the period of incubation of tomato wilt disease.

Since powdery mildew on tomato was reported in 1978, the tomato fields in the North and Northeast of Thailand were investigated for this disease. The symptom and the causal organism of the disease was studied in the field and laboratory. The powdery mildew of weeds and other crops nearby the tomato fields was also investigated. The disease was found in Khon Kaen, Nongkai, Tak, Lampang and Chiengmai. The symptom was described and the causal fungus was identified as Oidiopsis sp. The fungus Oidiopsis sp. not only caused powdery mildew on tomato, Lycopersicon esculentum, var. 360 Foutune, Rofoto, Ventura, CPC 2, VF 65, highest 22, Cal-J, and Romulus VFN, but also on other weeds and crops Solanaceae, Capsicum anuum, Euphorbiaceae Euphorbia hirta, and Compositae, Tragopogon porrifolius. It is predicted that the disease will be one of the important diseases of tomato in Thailand in the future.

Since powdery mildew on tomato was reported in 1978, the tomato fields in the North and Northeast of Thailand were investigated for this disease. The symptom and the causal organism of the disease was studied in the field and laboratory. The powdery mildew of weeds and other crops nearby the tomato fields was also investigated. The disease was found in Khon Kaen, Nongkai, Tak, Lampang and Chiengmai. The symptom was described and the causal fungus was identified as Oidiopsis sp. The fungus Oidiopsis sp. not only caused powdery mildew on tomato, Lycopersicon esculentum, var. 360 Foutune, Rofoto, Ventura, CPC 2, VF 65, highest 22, Cal-J, and Romulus VFN, but also on other weeds and crops Solanaceae, Capsicum anuum, Euphorbiaceae Euphorbia hirta, and Compositae, Tragopogon porrifolius. It is predicted that the disease will be one of the important diseases of tomato in Thailand in the future.

A disease survey was conducted to obtain basis information on the diseases of vegatables. Leaf mold and late blight were serious foliar disease in tomato during the seedling stage, especially when the infected seeds were sown. The diseases increased rapidly 35 days after seedling. Downy mildew of cucumber was severe in the Jinju and Suncheon area, however, it was not so serious in Namji area. Cucumber mosaic virus disease was prevalent in the areas surveyed and the disease incidence was increased rapidly after June. Powdery mildew prevailed at the early stage of cucumber growth after transplanting in the Namji area. Root rot and wilting caused by Phytophthora capsici was the most destructive disease in pepper grown in the vinyl house, especially in the Namji and Jinju area where the proper has been cultivated intensively. The phytophthora attacked most parts of young plants during the winter time and then induced crown rot on the adult plants. Cultivation of pepper in vinyl house was almost impossible because of the Phytophthora disease. Virus diseases in tomato plants were prevalent throughout the surveyed area and the damage was also severe. In the Jinju and Gimhae area, leaf mold and late blight showed high infection rate in tomato during the harvest time

The objective of the study was to relate tomato fruit yield and N uptake to water application rates via a trickle irrigation system at given N rates and to total water potential in the soil root volume. This information is needed to improve tomato cropping management under point source irrigation. The experiments were conducted on sandy soils at three different locations in Israel and included combinations of several daily N and water application rates, and two irrigation intervals. Fruit yield responded linearity to increasing total irrigation rates (Qw) up to 80% of the accumulated evaporation from a U.S. Class A pan (Eₚ), the slope of the response line being 15 metric tons/ha for each 10% change in Qw/Eₚ. The optimum average N concentration in the irrigation solution was determined to be 130 ppm N, below which yields and growth were inhibited and above which the soil water potential Ψ decreased, thus increasing the dry matter content of the fruit. A decrease in Ψ from −50 to −150 centibars appreciably decreased fresh fruit yield; a further decrease in Ψ caused a slower decrease in fresh fruit yield.