Due to the impoverishment of agricultural and horticultural soils and replant diseases, there is a need to use bioproducts and beneficial microorganisms in order to improve the quality of soils and growth substrates. For this reason, research was undertaken to assess the impact of arbuscular mycorrhizal fungi and rhizosphere bacteria on changes in soil microbiology, the degree of colonization of plant roots by mycorrhizal fungi, selected physiological parameters, and fruit quality and yield of the strawberry cultivar “Rumba.” The plants were inoculated with the mycorrhizal preparation Mykoflor (Rhizophagus irregularis, Funneliformis mosseae, Claroideoglomus etunicatum), MYC 800 (Rhizophagus intraradices), and the bacterial preparation Rhizocell C (Bacillus amyloliquefaciens IT45). The applied preparations increased the total number of bacteria and fungi in the soil and mycorrhizal frequency in the roots of the strawberry plants. They increased the chlorophyll “a” and total chlorophyll concentrations in the leaves as well as the rate of transpiration and CO₂ concentration in the intercellular spaces in the leaves. The plants treated with Rhizocell C and MYC 800 exhibited a higher CO₂ assimilation rate than control plants. The biopreparations increased chlorophyll fluorescence parameters such as maximum fluorescence (F_M) and the maximum potential photochemical reaction efficiency in PS II (F_V/F_M). The influence of the species of rhizosphere bacteria and mycorrhizal fungi used in the experiment on the physiological traits of strawberry plants contributed, especially in the second year of the study, to increase the yield and mean weight of strawberry fruit.

Although the application of chemical fertilizers to crops promotes plant growth and yield, their continuous use affects soil heath and creates environmental pollution. On the other hand, plant biostimulants improve nutrients absorption, plant growth, yield and produce quality and are environment-friendly. Therefore, an experiment was conducted during 2021-22 to evaluate the effect of some biostimulants on the performance of the apple cv. Anna, planted in a sandy loam soil at Marsa Matruh governorate, Egypt. Ninety trees were randomly selected and sprayed with 4 or 6% moringa leaf extract (MLE), 0.3 or 0.4% seaweed extract (SWE), 1000 or 2000 mg L⁻¹ Fulvic acid (FA), 4% MLE + 0.3% SWE + 1000 mg L⁻¹ FA (combination 1), or 6% MLE + 0.4% SWE + 2000 mg L⁻¹ FA (combination 2) before flowering, during full bloom and one month later and compared with a control (untreated trees). The results demonstrated that spraying MLE, SWE or FA or their combinations positively improved the vegetative growth, fruit set %, fruit yield and fruit physical and chemical characteristics as well as leaf nutritional status. The positive effect of MLE, SWE and FA was increased in parallel to an increase in the used concentration of each one of them. The highest increments in the measured parameters were accompanied by the application of combination 2 over the other treatments.

Sas-Paszt, L., Pruski, K., Żurawicz, E., Sumorok, B., Derkowska, E. and Głuszek, S. 2014. The effect of organic mulches and mycorrhizal substrate on growth, yield and quality of Gold Milenium apples on M.9 rootstock. Can. J. Plant Sci. 94: 281–291. A 3-yr study was conducted to evaluate the effects of organic mulches and mycorrhizal substrate on growth and yield of apple cv. Gold Milenium grown on M.9 rootstock. Straw (rye), pine bark, conifer tree sawdust, compost (plant debris), cow manure, peat moss substrate (commercial), and mycorrhiza substrate (Mykoflor^®, containing mycorrhizal fungi: Glomus intraradices, G. mosseae, G. etunicatum) were applied in spring of each year. All the applied treatments did not affect significantly the tree growth. Mulches did not have a positive effect on total soluble solids of the fruit and the number of fruits in different size categories. Only sawdust mulch significantly increased the number of fruit in size diameter class of 7.0–7.5 cm compared with the control. The use of mulches affected the concentration of macro- and microelements in leaves, particularly Cu, Fe, Mn and Zn. Mulches positively affected the pH and organic matter content of soil. The best results were observed with the use of the compost, cow manure and the mycorrhizal substrate, where the concentrations of P, K and Mg, most of microelements and soil organic matter were elevated.

Saskatoon berry has become as important as a commercial fruit crop. One main goal is to release new plant cultivars well adapted to different climatic and soil conditions. Dormant seeds obtained from breeding are serious problems delaying the program. The seeds were directly extracted from fruits after harvest (unstored) or after storage at −18 °C for 6 months (stored) and subjected to modified stratification (3 °C) with KNO₃, H₂O₂, NO, smoke-water (SW) or scarification using sandpaper or H₂SO₄ for 10, 20, 30, 40 min or treatments with pulsed radio frequency (PRF) or red light. The seeds were also subjected to warm–cool stratification (20/3 °C). Unstored seeds germinated in a higher percentage and with better uniformity (T₇₅–T₂₅) than stored seeds. Stored seeds positively affected the onset of seed germination (T₁) and mean germination time (MGT). Dormancy breakage was promoted by stratification with KNO₃, SW or scarification with sandpaper, H₂SO₄ or treatments with PRF. The recommended method for the breeding program of breaking seeds dormancy is when unstored seeds are subjected to stratification in KNO₃ (0.2%) or SW (1:100). Depending on the applied methods, the percentage of seeds’ germination increased to 87% compared to untreated (64%) control seeds. The positive effects of the selected methods persisted during seedling development by stimulating their growth and enhancing the chlorophyll content index (SPAD) and effective quantum yield of PSII of chlorophyll in leaves (ΦPSII).

Influence of bioproducts and mycorrhizal fungi on the growth and yielding of sweet cherry trees | Sławomir Głuszek, Edyta Derkowska, Lidia Sas Paszt, Mirosław Sitarek, Beata Sumorok | Agricultural Journals