The experiments were executed on the autumn and the winter of (2016 /2017, 2017/2018) seasons at Qalyub area, EL-Qalyubia governorate, Egypt. The main objective for this study to find out the efficacy of several biological and the chemical controls on growth and productivity of lettuce crop and management on white rot disease caused on Sclerotinia sclerotiorum. Thus, four treatments were applied as follow 1- the control (water application),2- Trichoderma asperellum, 3-Salicylic acid and 4- Calcium Chloride, which were evaluated and compared for the three fungicide as follow : 1- Iprodione , 2- Tebuconazole with Fluopyram and 3-Tebuconazole at the doses (85 & 100 ; 200 &100 and 50 &100 g or ml / 100L-1 respect.) . Which they tested for their ability for increasing the lettuce crop productivity and suppress mycelial growth of S. sclerotiorum pathogen by treatments were sprayed on two times on plants at (15-19 BBCH) stages by using backpack sprayer by 250 L./Fed.). Results indicated that, Iprodione applications significantly gave the highest indications of total and the Marketable yield in compared with the other experimental treatments for both seasons. Moreover, the two times of sprayes by Iprodione and Salicylic acid treatments had significantly lowered the disease incidence and disease severity and increasing the control efficiency in the both seasons. Whereas, the other treatments, Tebuconazole with Fluopyram or Tebuconazole and Trichoderma asperellum had a moderate effecacy on the lettuce crop productivety or the disease severity and incidence of Sclerotinia sclerotiorum in compared to the control treatment. In the contrast, application by Calcium Chloride had a low effect on the average yield or final yield as a mass and marketable plant in the both seasons and had insignificant effect on the disease severity or incidence of S. sclerotiorum despite low to medium recovery following applications. Finally, the control treatment was the lowest.

In this study, chemical and bio-control agents were  evaluated for their efficiency to control of  citrus fruit-rot disease  caused Alternaria citri  (K2) both, in vitro and in vivo trials. The most effective fungicides were score, montro and Iprodione compared with other fungicides depend on Ec50 and Ec90. While, the fungicide Pyraclostrobine had moderate effect on linear growth of A.  citri. Meanwhile, the Coprax, Coprareekh and Azoxystrobine were the least effective fungicide at Ec90.  Trichoderma harzianum and Bacillus subtilis tested showed antagonistic action effect to a highly pathogenic isolate of Alternaria citri, with different degrees of inhibition. T. harzianum was the most effective compared with B. subtilis, in vitro trials. Also, all fungicides were evaluated on incidence of citrus fruit rot disease in vivo trials.  The disease incidence was reduced, but with different degrees. In addition, using T. harzianum, B. subtilis, B. megaterium (Bio-ARC) and Trichoderma   album (Bio-Zeid) decreased    incidence of citrus fruit rot disease. On the other side, T. harzianum showed the highest suppressive effect against citrus fruit rot pathogen. Generally, all tested fungicides and bio-agents were effective against the causal fungus in vitro and in vivo trials, but with different degrees.

Late blight caused by Phytophthora infestans is one of the most destructive dis-eases potato in Egypt and world wide. Stability of resistance to late blight was eva-luated in twenty five potato cultivars during 2003 and 2004 successive seasons un-der heavy natural infection. Data showed that the potato cultivars Altesse, Occania, Safrane and Soleia highly resistant while cultivars Daisy, Hermine and Isabel rec-orded the highest susceptibility to late blight. Application different fungicide against potato late blight revealed that Aquagen Bro and Previcur-N were the best effective fungicides in reducing disease severity and progress of late blight. Data showed also that the losses of tubers due to late blight in season 2003 ranged from 11.75 Kg/plot (cultivar Hermes) to 18.0 Kg/plot (cultivar Lady Roseta) while in season 2004, yield losses ranged from 11.25 Kg/plot (cultivar Hermes) to 23.75 Kg/plot (cultivar Spun-ta). The results demonstrate that integration of Previcur-N treatment with host resis-tance was effective in reducing late blight and tuber yield loss of potato.

Guava (Psidium guajava L.,) die-back disease caused by Botryodiplodia theobromae Pat., is a destructive disease, considered one of the most important and economic disease of guava. Amistar Top 325-32.5% E.C. gave the highest decreasing of linear growth and amount of growth of isolate code No., Q.K.4., followed by Camzin 50% W.P., Monceren 25% W.P. and Montro 30% E.C. Meanwhile, Ridomil Gold/Plus 42.50% W.P., Copral 50% W.P., Eminent 12.50% E.W. and Thiovat Jet 80% W.G. exhibited a lowest effect in reducing of linear growth and amount growth of B. theobromae isolate code No., Q.K.4. Amistar Top 325-32.5% E.C. was the most efficient fungicide in reduce disease incidence and disease severity infield of B. theobromae isolate code No., Q.K.4., followed by Camzin 50% W.P., Monceren 25% W.P., Montro 30% E.C. Meanwhile, Ridomil Gold/Plus 42.50% W.P., Copral 50% W.P., Eminent 12.50% E.W. and Thiovat Jet 80% W.G. showed a lowest efficient in reducing the disease incidence and disease severity. Soil drench method of fungicides application was the higher efficient method in elimination of percentage of disease incidence and disease severity followed by foliar spray application, relatively. Banaty transplant was the most susceptible cultivar to the all tested B. theobromae isolates, whereas cultivar Gizy Ahmr was the lowest susceptible with the same isolates, information about cultivar reaction of guava transplants against B. theobromae is still scanty.