AUTHOR=Matsumoto Ryo , Asfaw Asrat , Ishikawa Haruki , Takada Kanako , Shiwachi Hironobu , Asiedu Robert 

TITLE=Biomass production and nutrient use efficiency in white Guinea yam (Dioscorea rotundata Poir.) genotypes grown under contrasting soil mineral nutrient availability

JOURNAL=Frontiers in Plant Science

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2022.973388

DOI=10.3389/fpls.2022.973388

ISSN=1664-462X

ABSTRACT=Yam (Dioscorea spp.) is of great importance to food security, especially in West Africa. However, the loss of soil fertility due to dwindling fallow lands with indigenous nutrient supply poses a challenge for yam cultivation. This study aimed to determine shoot and tuber biomass and nutrient use efficiency of white Guinea yam (Dioscorea rotundata) grown under low- and high-NPK conditions. Six D. rotundata genotypes were used in field experiments conducted in Ibadan, Nigeria. Experiments were conducted with low soil NPK conditions with zero fertilizer input and high soil NPK conditions with mineral fertilizer input. Varietal differences in response to soil NPK conditions, nutrient uptake, and nutrient use efficiency (apparent nutrient recovery efficiency) were observed among the tested genotypes. The genotypes TDr1499 and TDr1649, with high soil fertility susceptibility index (SFSI>1) and an increase in shoot and tuber biomass with fertilizer input, were recognized as susceptible to soil NPK conditions. There was a marked difference in apparent nutrient recovery efficiency but no varietal difference in physiological efficiency. The difference in apparent nutrient recovery efficiency affected the fertilizer response (or susceptibility to soil NPK conditions) and the nutrient uptake in the white Guinea yam. In contrast, the genotype TDr2029, with SFSI<1 and low reduction in shoot and tuber production between non-F and +F conditions, was recognized as a less susceptible genotype to soil NPK conditions. Our results highlight genotypic variation in sensitivity to the soil NPK availability, nutrient uptake, and nutrient use efficiency in white Guinea yam. The difference in susceptibility to soil NPK conditions could be due to the difference in nutrient recovery efficiency in white Guinea yam. These findings could contribute to breeding programs to develop improved white Guinea yam varieties that enhance productivity in low soil fertility conditions with low and high-input farming systems.