The root diameters as well as colonization and diversity of the root-associating fungi of Vaccinium oldhamii Miq. were investigated in order to obtain information on their mycorrhizal properties. The distal regions of roots had typical hair roots with diameters of less than 100 μm. Ericoid mycorrhizal fungi (ErMF) and dark septate endophytes (DSE) were frequently observed in the roots. Ascomycetes, particularly helotialean fungi, appeared to be dominant among the endophytic fungi of V. oldhamii roots. Furthermore, Rhizoscyphus ericae (Read) Zhuang & Korf and Oidiodendron maius Barron known as ErMF were detected more frequently than other fungal species.

Pruning is a recommended cultural practice in blueberries (Vaccinium spp.) to maintain the balance between vegetative growth and reproductive development. Winter pruning is common and well-documented practice. Summer pruning, however, has been less studied. In this study, 5 primaryshoots (PSs) were selected per treatment (pruning date) on 5 different bushes (replications) of the rabbiteye blueberry (Vaccinium virgatum Ait.) 'Tifblue' and half-length headed back during its active growth period from June through Nov. The hypothesis tested in this study was that summer pruning induces flower buds at the basal area of PSs, controls the plant canopy and makes it possible to harvest fruits in the next summer season from the same shoots. In this study, there were no significant differences observed among any treatments with respect to yield and fruit quality. Early summer pruning (June) stimulated secondaryshoots (SSs) and later in autumn, terminal flower buds of these SSs produced fruits in the following year. However, no SSs were produced after summer pruning in Sept., and only vegetative buds that were at the basal area of PSs differentiated to flower buds and produced fruits in the following year. In conclusion, summer pruning can be practiced to complement or replace winter pruning and growers could decide the date of summer pruning in accordance with the size of plants' canopies. Plants with smaller canopies can be pruned in June and those with bigger canopies can be pruned in Sept.

Moderately vigorous shoots of mature rabbiteye blueberry ‘Tifblue’ bushes were pruned in summer to clarify the effects on vegetative and reproductive traits. Treatments included un-pruned, 25% pruned (removing 25% of the shoot length), 50% pruned (removing 50% of the shoot length) and 75% pruned (removing 75% of the shoot length). Vegetative and flower bud number per shoot decreased with increasing pruning severity. Consequently, the number of laterals per shoot dropped. However, lateral length increased with increasing pruning severity. Shoots pruned at 75% produced a small number of laterals, but they were the most vigorous. Pruning severity induced the transition of vegetative buds to reproductive buds in areas lower than the cut position. The flower bud number per shoot decreased with increasing pruning severity. However, yield per shoot was not affected due to a compensatory increase in berry weight. Total soluble solids content and titratable acidity of the berry juice, as well as, the number of berries per flower bud were not affected. Hence, to reduce the unproductive parts of the plant, and to produce bigger berries, September removal of either 50% or 75% of the length of mature rabbiteye blueberry shoots under conditions similar to the Kanto region of Japan is recommended.

Phosphorus (P) availability in soils is often constrained by its accumulation in non-labile phosphorus (NLP) forms, limiting its accessibility to plants. This study examines how soil physical properties, chemical characteristics, and climatic conditions influence phosphorus fractionation and the transformation of NLP into plant-available labile phosphorus (LP). Utilizing global structural equation modeling (SEM), we found that silt content enhances organic phosphorus fractions, including NaHCO₃-Po and NaOH-Po. In the upper 30 cm of soil, pH decreases the availability of NaHCO₃-Po and NaOH-Po while stabilizing NLP, highlighting its essential role in phosphorus cycling under acidic conditions. In deeper soil layers, pH facilitates phosphorus mobilization from NLP pools, with effects varying across fractions. Long-term studies on Japanese Vaccinium soils reveal that pH and electrical conductivity (EC) management significantly promote NLP-to-LP conversion, primarily through NaOH-Po, thereby improving phosphorus use efficiency. These findings underscore the critical importance of prioritizing chemical property management over physical modifications to optimize nutrient cycling, preserve soil fertility, and reduce reliance on external phosphorus inputs in agricultural systems. Our study emphasizes the need for integrated approaches to achieve sustainable phosphorus management in both natural and managed ecosystems.