Summary• Here, orthologous genes of six phosphate transporter (PiT) genes, which are members of the Pht1 and Pht2 families in tomato and potato, have been cloned from the solanaceous species pepper, eggplant and tobacco.• Overall, expressions of these genes in pepper, eggplant and tobacco showed similar patterns to those in tomato and potato: P-starvation enhancement in both leaves and roots for Pht1;1 , P-depletion induction exclusively in roots for Pht1;2 , mycorrhizal enhancement for Pht1;3 , and mycorrhizal induction for both Pht1;4 and Pht1;5 .• In the roots of nonmycorrhizal eggplant, SmPht1;3 , SmPht1;4 and SmPht1;5 were also expressed under extreme P starvation. Mycorrhizal symbiosis under high-P supply conditions reduced plant growth, with concurrent enhancement of Pht1;2 expression in the roots of pepper as well as eggplant. In addition, the mycorrhizal symbiosis down-regulated the expression of Pht2;1 genes greatly in the leaves of pepper and tobacco.• The discrepancies between the evolutionary distances of the PiT genes and their expression patterns among the five species suggest greater complexity in function of PiT in plants than previously expected.

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Cotton verticillium wilt (Verticillium dahliae Kleb.) is a very destructive disease. In this study, we evaluated a Bacillus subtilis enhanced bio-organic fertilizer (BOF) for control of the disease and for its eff ect on rhizosphere microbiota. Greenhouse pot experiments were conducted during three cotton (Gossypium hirsutum L.) growing seasons with serial treatments of BOF or unenhanced organic fertilizer (OF). Consistent control of cotton verticillium wilt was obtained in the three trials. Th e complete BOF treatment, in which both nursery cups with healthy soils and transplanted pots with diseased soils were amended with BOF, was the most eff ective in reducing the counts of pathogenic V. dahliae and of total fungi in the cotton rhizosphere. Th e complete BOF treatment was also the most eff ective in reducing disease incidence. Rhizosphere soil DNA was extracted at harvest and the 5´ end (370 base pairs) of the fungal 18S rRNA gene was amplifi ed by using the primer pair NS1 and GCFung (fungus specifi c). Seventy-one bands were recognized in denaturing gradient gel electrophoresis (DGGE) gels and excised for sequencing, but only 35 bands were successfully sequenced during the study. Nonmetric multidimensional scaling analysis of DGGE patterns showed that the complete BOF treatments were not close to any other treatment. Ribotypes related to four Ascomycota and two Basidiomycota fungi were detected in the untreated but not in the BOF-amended soil. Th e results suggest that the complete BOF treatment could eff ectively control cotton verticillium wilt by signifi cantly improving fungal structure in rhizosphere soils.

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