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Background Since the root nodules formation is regulated by specific and complex interactions of legume and rhizobial genes, there are still too many questions to be answered about the role of the genes involved in the regulation of the nodulation signaling pathway. Results The genetic and biological roles of the isoflavone-7-O-beta-glucoside 6″-O-malonyltransferase gene GsIMaT2 from wild soybean (Glycine soja) in the regulation of nodule and root growth in soybean (Glycine max) were examined in this work. The effect of overexpressing GsIMaT2 from G. soja on the soybean nodulation signaling system and strigolactone production was investigated. We discovered that the GsIMaT2 increased nodule numbers, fresh nodule weight, root weight, and root length by boosting strigolactone formation. Furthermore, we examined the isoflavone concentration of transgenic G. max hairy roots 10 and 20 days after rhizobial inoculation. Malonyldaidzin, malonylgenistin, daidzein, and glycitein levels were considerably higher in GsMaT2-OE hairy roots after 10- and 20-days of Bradyrhizobium japonicum infection compared to the control. These findings suggest that isoflavones and their biosynthetic genes play unique functions in the nodulation signaling system in G. max. Conclusions Finally, our results indicate the potential effects of the GsIMaT2 gene on soybean root growth and nodulation. This study provides novel insights for understanding the epistatic relationship between isoflavones, root development, and nodulation in soybean. Highlights * Cloning and Characterization of 7-O-beta-glucoside 6″-O-malonyltransferase (GsIMaT2) gene from wild soybean (G. soja). * The role of GsIMaT2 gene in the regulation of root nodule development. *Overexpression of GsMaT2 gene increases the accumulation of isoflavonoid in transgenic soybean hairy roots. * This gene could be used for metabolic engineering of useful isoflavonoid production.

The potential of macroalgae as biostimulants in agriculture was proved worthy. Vicia faba and Helianthus annuus are socioeconomic crops owing to their increasing demand worldwide. In this work, we investigated the energetic role of seed presoaking and irrigation by the brown seaweed, Sargassum polycystum aqueous extract (SAE) on certain germination and growth traits, photosynthetic pigments, carbohydrates, phenolics, flavonoids, and the total antioxidant activity. Compared to the control plants, our consequences revealed that seeds that received the SAE improved all the germination and growth criteria for both crop plants. Furthermore, the SAE significantly increased the carotenoids, total photosynthetic pigments, and total carbohydrates by (14%, 7%, and 41%) for V. faba and (17%, 17%, and 38%) for H. annuus, respectively. Phenolics and flavonoids were significantly induced in Vicia but slightly promoted in Helianthu plants, whereas the total antioxidant activity in both crops non significantly elevated. Even though The NPK contents were significantly stimulated by the SAE in Vicia plants, the effect was different in Helianthus, where only nitrogen content was significantly enhanced, whereas phosphorus and potassium showed little enhancement. Thus, the SAE treatment is one of the superlative sustainable strategies for food, feed, and as excellent plant conditioner.

This work was conducted to study the effect of different temperatures (20, 25 and 30°C) on biological aspects of predatory mite, Phytoseiulus persimilis Athias -Henriot, 1957[1] (Acari: Phytoseiidae). The developmental periods of P. persimilis was shortened with increasing temperature. Incubation period of P. persimilis, was 2.45 days at 30°C followed by 2.84 at 25°C and 5.04 days at 20 °C, respectively. The life cycle of P. persimilis female differed according to temperature degree, its shortest period was 6.45 days at 30°C, while its longest period 12.03 days at 20 °C. Total immatures of P. persimilis consumed more preys at high temperature compared with low temperature; it was 21.32, 14.81 and 11.37 preys for females at 30, 25 and 20 °C respectively. Also females consumed higher numbers of preys at the ovipostion period reached to 127.94, with maximum average fecundity (43.17 eggs) was deposited by female at 30 °C followed by 25°C (37.00 eggs) ,whereas the longest period was recorded at 20°C with an average of 29.75 eggs/female. P. persimilis proved to be a good bio-control against Tetranychus urticae infesting strawberry plants under field conditions at release ratios 1:5, 1:10 and 1:15 predator / prey. Reduction percent appeared one week after release, generally it revealed 71.38, 62.89 and 22.16 % mean reduction for each release ratios after 8 weeks, respectively. The releasing of P. persimilis at level 1:5 gave the best results of bio-control of T. urticae.

Survey was conducted to identify phytophagous, predaceous and miscellaneous feeding mite species from five locations in Qalubia governorate (Arab Elhassania, Arab Alkhilwa, Meet Kinana , Namol , Eldar) on two strawberry cultivars during two successive season (2019/2020 and 2020/2021). Taxa reported the occurrence of thirty-nine species representing of sixteen families. Among the species, eight belonging to tetranychid and tenuipalpid mite species dominated by Tetranychus urticae. Seventeen species of predators belonging to six families are recorded (Phytoseiidae, Ascidae, Stigmaeidae, Cunaxidae, Bdellidae and Digamasellidae). The most common predator on plants was Phytoseiulus persimilis Athias-Henriot. Population dynamics of Tetranychus urticae Koch and its predator Phytoseiulus persimilis were recorded on two strawberry cultivars during the two seasons. The population of T. urticae reached their high peaks of infestation in the third week of March and the first week of February (12.63 & 35.60) during 2019/2020 and in the last week of January and February (9.30 &15.93) mean number /30 leaflet during 2020/2021 for moving stages, Fortona and Florida cultivars respectively. The phytoseiid mite, P. persimilis was recorded in association with the population of T. urticae, when it appeared in high peak in the first week of March and the first of January (2.33&4.40 and 2.43& 1.95) mean number /30 leaflet for moving stages during the two seasons of the study respectively. Populations of T. urticae and P. persimilis showed a positive correlation with average temperature and negatively correlated with relative humidity.