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Mollisols are naturally fertile soils with a thick, friable, very dark coloured, organic rich, surface layer (mollic epipedon). Soils literature for 20 South Pacific island countries was examined for information on Mollisols; of these countries, 16 had confirmed Mollisols. Given the basic concept of Mollisols (continental grassland soils), this was an unexpected prevalence. Classifications using the USDA Soil Taxonomy identified 4 suborders, 10 great groups, and 33 subgroups of Mollisols occurring in the South Pacific region. Some taxonomic issues were identified, and these are addressed and changes to better accommodate Mollisols important for the South Pacific region are suggested. The importance of Mollisols in the region is summarised by reviewing their occurrence and uses, especially in food production.

A field experiment was carried out with an aim to study the influence of two strains of Penicillium bilaii (PB -201 and PB-208) inoculation along with superphosphate application on growth, yield and P uptake of wheat (cv. PBW-343) and, also to examine the inoculation effect on P availability, forms of P and soil properties in Mollisols of Uttarakhand, India. The results showed that both strains of P. bilaii effectively solubilized tri-calcium phosphate in Pikovskaya agar medium, which was much higher over native fungal isolates. Wheat seed inoculation with P. bilaii strains along with superphosphate levels significantly influenced shoot height, shoot dry weight, number of total and effective tillers, yield attributes, yield components, tissue content and uptake of P. The treatment T7 (P. bilaii, strain PB-208 + 50% P) has resulted into the highest amount of shoot height (87.9 cm at 90 DAS), shoot dry weight (1.5 and 3.8 g at 60 and 90 DAS, respectively), grain (66.8 q ha-1) and straw yield (42.7 q ha-1) and P uptake (26.5 kg ha-1). The Olsen-P, organic carbon, dehydrogenase activity and fungal populations also increased in soil inoculated with P. bilaii strains combined with superphosphate application compared to the control soil. The conjoint use of the fungal strains with or, without P fertilization has developed an antagonistic interaction that has caused decline in yield, tissue content and uptake of P and its availability in soil. In conclusion, it is possible to reduce the rate of soluble P-fertilizer added by 50% without reducing yield, if wheat is inoculated with P-solubilizing fungi like P. bilaii.

Hybrid of corn are widely grown since early 2000s by smallholders in the western areas of Cambodia. A large number of hybrids are available on the market.

Hybrid of corn are widely grown since early 2000s by smallholders in the western areas of Cambodia. A large number of hybrids are available on the market.

Characterization of Labile Fractions of Soil Organic Carbon in Mollisols from different climatic regions. The research studied the potential mineralization and characterization of labile SOM of different types of Mollisols: Hapludolls, Argiudolls, Calciustolls, and Haplustolls. Labile C fractions distributed oppositely than total SOC and were the greatest in Calciustolls and the lowest in Hapludolls. The amount of soil microbial biomass C (MBC) was significantly higher in dry than in wet regions. The highest amount of light fraction C was in dry-thermic followed by dry-frigid, and the least amount was in wet regions. Dry regions were able to retain a higher level of labile C than the moist regions, due to a slower annual decomposition rate.