الفهرس 
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Abstract
The current study was conducted at a private Farm in Qalin district, Kafr El-Sheikh Governorate during two successive growing seasons of soybean, Glycine max (L.) 2019 and 2020 to studied:- 1- Examine the impact of using SA and SMS as inducers on population density of whitefly and the associated common predators in soybean field. 2- Analyze the impact of utilizing SA and SMS as inducers on specific biochemical components within soybean plants. 3- Assess the effects of using SA and SMS as inducers on selected plant parameters of soybean plants. 4- Evaluate the effect of both SA and SMS as inducers on certain biological aspects of whitefly, Bemisia tabaci (Gennadius) reared on soybean plants. The obtained results could be summarized as follows: 1: Effect of SA and SMS on germination and certain seedling traits of soybean 1.1. Effect on germination The results indicated that the suitable period for soaking soybean seeds on germination and some seedling parameters were 4th hours. This period induced significant increase in seed germination. The treated seeds with SA recorded high percentage of germination (91.7%) in both soybean varieties respectively, while SMS recorded 88.3% and 91.7% in Giza 111 and Giza 35, respectively. 1.2. Effect on seedling growth Generally, there were increases in shoot, root length and fresh weight of seedlings in all treatments relative to untreated control. The rate of increase was higher at SA treatment than SMS. In term of plant development at 4th hours of seed soaking, the treatment with SA increased the shoot length by 8.48 cm and 8.54 cm for G111 and G35, respectively, while the increase was 8.2 cm and 8.16 cm in case of SMS treatment for G111 and G35 respectively compared with untreated control. As for the root length at 4th hours of seed soaking, SA treatment caused significant increase by 7.86 cm and 8.1cm for G111 and G35 respectively, while SMS induced an increase by 7.74 cm and 7.58 cm for G111 and G35 respectively compared with control. 2. Effect of SA and SMS as inducers on population density of whitefly in soybean field 2.1. Whitefly adults A significant decreasing in whitefly adults compared to the control was observed. T4 for SA treatment was the least mean number of whitefly adults population for Giza 111 and Giza 35 varieties during 2019 and 2020 seasons by 36.4 ± 1.18, 38.56 ± 1.97, 36.21 ± 0.67 and 35.90 ± 0.85 insects/15 leaflets respectively. While, T5 treatment (SMS) was the lowest of whitefly adult population for Giza 111 and Giza 35 during 2019 and 2020 seasons by 36.3 ± 1.02, 36.96 ± 0.98, 35.27 ± 0.6 and 34.60 ± 1.48 insects / 15 leaflets, respectively. SMS treatments were most efficient in reducing the number of whitefly adults on two soybean varieties during two study seasons compared with SA treatments. Also, soaking seeds + spray by SA and SMS treatments (T4 and T5) were the best compared with other treatments. Regarding the Giza 111 variety during the 2019 and 2020 seasons, the decrease in population occurred in T4 and T5 treatments by 28.6% and 28.8 % for 2019 season and 29.9 % and 31.7 % for 2020 season, respectively. As for the Giza 35 variety, the largely reduced of whitefly adult population was 25.1 % and 21.8 % for T4 and T5 treatments in 2019 season. Also, in the 2020 season the reduction was 11.9 % and 15.0 % for T4 and T5 treatments, respectively. No significant differences between the two study seasons for the population density of whitefly adults in Giza 111 variety except, T2 treatment. While, in Giza 35 variety only T1 and T7 treatments were significant during two study seasons. Also, no significant differences of whitefly adults population density between the two varieties for all the treatments during the first season, while the second season was significantly higher differences between two varieties for T1, T6 and T7 treatments. 2.2. Whitefly nymphs The most dense treatment to nymphs was T6 for two varieties duri ng two seasons by 67.1 ± 0.73, 55.96 ± 0.81, 75.06 ± 1.66 and 57.88 ± 2.0 insects / 15 leaflets, respectively. The lowest numbers observed in T5 and T4 treatments for two varieties during two study seasons. Also, it was found that SMS treatments contained fewer whitefly nymphs than SA treatments and the seed soaking + spray treatments (T4 and T5) for both compounds under study gave the highest results in reducing the population of whitefly nymphs. Regarding which of the two varieties was most affected by the whitefly nymphs, the results showed that the Giza 111 variety was the highest of number compared with Giza 35 variety. For Giza 111 variety, the T5 and T4 treatments were the most effective in reducing the number of whitefly nymphs during two study seasons by 26.9% and 26.0% for 2019 season and 23.3% and 21.0% for 2020 season, respectively. On the other hand, T6 treatment was the lowest during two seasons 2019 and 2020 by 20.3% and 7.4 % respectively. As for Giza 35 variety, the treatments of T 4 and T5 reduced the nymph population of B. tabaci by 34.7% and 33.7% during 2019 season, while in 2020 season the highest rate of population reduction occurred in T5 and T4 by 13.4% and 11.3%, respectively. The application of both resistance inducers suppressed whitefly infestation compared to control. SMS treatments were more effective than SA treatments against both whitefly adults and nymphs. Seed soaking + spray treatments (T4 and T5) were the best compared with other treatments and Giza 35 variety, has lowest number of whitefly insect than Giza 111 variety. To compare seasonal mean of whitefly nymphs during 2019 and 2020 seasons on two soybean varieties Giza 111 and 35 treated with SA and SMS, results refer to no significant differences in the mean number between two study seasons for Giza 111 variety except T6 ( t = 4.42 p = 0.012) and T7 (t = 5.23 p = 0.0064) treatments. While, Giza 35 variety found significant differences in each of the following treatments only T3 ( t = 4.39 p = 0.012), T4 (t = 9.49 p = 0.0007) and T5 (t = 6.15 p = 0.0035). As for compare seasonal mean of whitefly nymphs on two soybean varieties results showed highly significant differences between two varieties for two study seasons, and Giza 35 had the least number of whitefly nymphs. 3. Effect of SA and SMS as inducers on population density of the common associated predators to whitefly in soybean field 3.1. Aphid lion, chrysoperla carnea (Steph.) predator (larvae) To determine the effect of the treatments on beneficial arthropod communities, natural enemies in both study seasons results indicated that in 2019 season T4 and T6 treatments for Giza 111 variety were the highest of Ch. carnea number by 9.58 ± 0.29 and 9.29 ± 0.15 larvae / 5 plants, respectively. As for 2020 season T6 treatment contained the highest number of Ch. Carnea by10.71 ± 0.49 followed by untreated control (10.00 ± 0.22). Regard to Giza 35 variety during 2019 season treatments of T2 followed by T1 were the highest of Ch. carnea number by 9.92 ± 0.14 and 9.88 ± 0.38 individual / 5 plants respectively, while in the second season (2020) T7 treatments was the highest by 10.94 ± 0.16 larvae / 5 plants. 3.2. Orius bug, Orius sp. predator (adult and nymph) For Giza 111 variety the highest mean numbers of Orius bug predator (adult and nymph) found in T6 treatment by 11.5 ± 0.47 individual / 5 plants during the first season, whereas in the second season the control was the highest one by 12.71 ± 0.08 predator / 5 plants followed by T2 treatment (12.31 ± 0.55). On the other hand for Giza 35 variety the control was the highest of mean number to Orius sp throw two study seasons compared with other treatments followed by T2 in the 2019 season and T7 in the 2020 season. 3.3. Coccinellidae family predators (larva + adult) The control treatments on two soybean varieties during two study seasons were the highest number of Coccinellidae family predators (larva + adult) compared with other treatments followed by T7 t reatments for the two varieties during two seasons except first season for Giza 111 variety the highest number observed in T6 treatment by 2.60 ± 0.11 individual / 5 plants. 3.4. Total insect predators Results showed the effect of different treatments on the number of treatments on the number of total insect predators associated with whitefly in soybean field. For Giza 111 variety, results showed that T6 and T2 treatments had the least effect on the total number of predatory insects by 1.8% and 4.1% to 2019 and 2020, respectively. While, T2 and T7 treatments were the least efficient in reducing the predators for Giza 35 variety by 2.5% and 3.3% to 2019 and 2020 respectively. Treatment of T5 was the highest effective in reducing the number of total insect predators during two study seasons for two soybean varieties. This is probably because T5 treatments were the lowest of infestation by whitefly, which predators feed on, among other treatments. The statistical analysis for Giza 111 variety showed significant differences between two seasons for every treatment except T4 treatment. On the other hand, only T7 treatment was highly significant differences compare with other treatments between two seasons for Giza 35 variety. To compare seasonal mean of total predator numbers on two soybean varieties Giza 111 and Giza 35 treated with SA and SMS during 2019 and 2020 seasons under field conditions, results confirmed that T2, T3, T5 and T7 treatments were significant differences between the two varieties during 2019 season. But, in season of 2020 the treatments of T2, T3, T4 and T5 were significantly different between them for both varieties. The effect of the predatory insects for all treatments on B. tabaci adults in soybean fields was positive and highly significant during both seasons for two soybean varieties. Giza 111 and Giza 35 varieties showed a correlation between an increase in whitefly adults and predators. As for whitefly nymphs, results showed that the regression coefficient was positive and highly significant in both seasons for soybean varieties in all treatments except T4 treatment for Giza 35 variety during two seasons. This means that the number of predators increases by one for every 2.366 to 4.339 insect nymphs and between 3.683 and 4.45 insects for Giza 111 variety during two seasons, respectively. In respect to Giza 35 variety, the increases of whitefly nymphs ranged from 1.112 to 2.869 and from 1.484 to 2.563 insect during two seasons, respectively. 4. Effects of SA and SMS as inducers on some biochemical contents of soybean plants 4.1. Effect on antioxidant enzymes Results showed that (CAT), (PPO) and (POX) activities were increased significantly for all treatments compared with control in two soybean varieties. In Giza 111 variety, the highest amount of three enzyme activities was recorded in T2, T6 and T5 treatments by 43.22%, 11.11% and 41.58% respectively, but the highest amount of three enzyme activities for Giza 35 variety was recorded in T5 treatment by 49.78%, 6.82% and 45.29% respectively. Increasing production of defensive enzymes induced defenses to adult and nymph of whitefly insect. 4.2. Effect on total protein content The Effect of treated soybean (Giza 111 and 35 varieties) with SA and SMS on change in total protein content was presented. It was observed that, treated seed + spray with SMS induced significantly the highest increase in total protein by 11.05% and 7.65% for Giza 111 and Giza 35 respectively, while the other treatments recorded moderate increase ranged from 1.58 to 9.47% for Giza 111 variety as compared to control. On the other hand, for Giza 35 variety, untreated seed + spray with SA treatment caused the lowest increase in total protein (1.02%). Data showed the simple correlation coefficient between whitefly infestation (adult and nymph) and antioxidant enzymes (CAT, PPO, POX) in addition to protein on two soybean varieties Giza 111 and Giza 35 under different treatments. Whitefly adult population correlated insignificantly negative with (CAT), (PPO), (POX) and protein in both varieties, except (POX) for Giza 111 variety, correlation was significant and negative. the same results were found for Whitefly nymph population, except (POX) enzyme, which had a significant negative correlation for two soybean varieties Giza 111 and Giza 35 as well as the protein of the Giza 35. 5. Effect of SA and SMS as inducers on some plant parameters of soybean plants Treatments of T4 and T5 were the highest of different growth criteria such as plant height, number of branches, fresh and dry weight and weight of 100 seeds compared with other treatments for two soybean varieties during 2019 and 2020 seasons. Regard to Giza 111variety during 2019 season, fresh weight alone of plant showed significant differences among treatments, but in 2020 season, plant height and fresh and dry weight were significantly different among treatments. As for Giza 35 variety during 2019 season, the statistical analysis of data conducted that each of the plant height and fresh and dry weight showed significant differences among treatments, while in 2020 season, plant height and fresh weight were significant between all treatments. Control treatment was the lowest in all previous measures in two varieties during two seasons. 6. Effect of SA and SMS as inducers on certain biological aspects of whitefly on soybean plants 6.1. Development of immature stages of whitefly Development of immature stages of whitefly on soybean Giza 111 variety showed that the average of incubation period did not differ amongst treatments its ranged from 6.2 to 7.83 days compared with control (6.0 days). With regard to the nymphal stages of the whitefly, there were differences between treatments for all instars except pupa instar period there were indifferences between treatments. The T4 treatment extended the first nymphal instar in relation to the other treatments. Also, the duration of the second and third instar was longest on T4 treatment. The averages for the total duration of egg-adult development of whitefly on different treatments ranged from 21.33 to 28.33 days. T4 treatment produced the highest average, followed by T5 treatment. The percentage of total mortality was significant higher on T5 treatment (36.7%) followed by T3 treatment (35.6%) compared to control (23.3%). Regard to Giza 35 variety, results referred to the immature total period of B. tabaci was significantly longer on T4 and T5 treatments by 28.17 and 27.83 days respectively, than on control (24.33 days), also the incubation period was significantly longer on T5 then T4 treatments (10.17 and 9.33 days respectively) than on control (7.83 days). For the period of other nymphal instars, was recorded insignificant difference between different treatments. The percentage of total mortality was higher on T5 treatment (41.1%) followed by T4 treatment (38.9%) compared to control (28.9%). 6.2. Adult stage and oviposition of B. tabaci on soybean The percentage of adult emergence, sex ratio, reproduction, longevity, life span and generation time of B. tabaci on different treatments of soybean plants were studied under laboratory conditions. Regard to Giza 111 variety the obtained data showed that, the lowest percentage of adult emergency occurred on T5 treatment (63.3%) followed by T3 treatment (64.4%). Also, the lowest percentage of female showed in T5 treatment (51.1 %), for pre-reproduction and reproduction period was insignificant differences amongst all treatments. The period of longevity was insignificant between all treatments compared with control treatment (30 days) while, the longer period of life span occurred on T4 treatment by 54.3 days compared with control (51.3 days). Based on Giza 35 soybean variety, statistical analysis revealed that the lowest percentage of adult emergency occurred on T5 treatment by 58.9% followed by T4 treatment (61.1%). Judging by percentage of other parameter such as male, female, sex ratio, pre-reproductive, reproductive, post- reproductive, adult female longevity, total life span of female and generation time the statistical analysis showed no significant differences between treatments.