Effect of crack generation on plant water uptake and quality and quantity of rice yield in heavy clay soil fields cultivated with paddy rice [Oryza sativa]

• Published in: Nippon dojō hiryōgaku zasshi Vol. 79; no. 5
• Main Authors: Kaneta, Y.(Akita Prefectural Univ. (Japan). Faculty of Bioresource Sciences), Takahashi, D, Sato, T
• Format: Journal Article
• Language: Japanese
• Published: 05.10.2008
• Subjects: ABSORCION DE AGUA; ABSORPTION D'EAU; AGRIETAMIENTO DEL SUELO; ARROZALES; CALIDAD; CLAY SOILS; ESMECTICAS; FISSURATION DU SOL; PADDY SOIL; QUALITE; QUALITY; RACINE; RAICES; RENDEMENT; RENDIMIENTO; RICE FIELDS; RIZIERE; ROOTS; SMECTITE; SMECTITES; SOIL CRACKING; SOL ARGILEUX; SOL DE RIZIERE; SUELO ARCILLOSO; SUELO DE ARROZALES; TRANSPIRACION; TRANSPIRATION; WATER UPTAKE; YIELDS
• ISSN: 0029-0610
• DOI: 10.20710/dojo.79.5_454

This study investigated the relationship between tillage method and crack generation in heavy clay soil fields cultivated with paddy rice on reclaimed land in Hachirogata, and analyzed the effect of crack size on plant water uptake and the quality and quantity of rice yield. Cracks in puddled fields appeared in 20 days after midseason drainage, and thereafter propagated rapidly and continuously until the end of August. The puddled fields contained a greater number of cracks than a non-puddled field. Stomatal apertures and transpiration of the rice flag leaves were higher in the non-puddled field with fewer cracks than in plants in the puddled fields. The rice roots on the field surface were frequently severed by the large cracks. The dry weight of the rice roots extending from the plants was 10-37% lower in the puddled fields than in the non-puddled field. Plant uptake of soil water and irrigation water were lower in the puddled field with large cracks than in that with small cracks. The number of panicles and the amount of unhulled rice did not differ among the three plots. The percentage of ripened grains and the thousand-grain weight were lower in the puddle field with large cracks. The rice yield decreased in order of the non-puddled field, the puddled field with small cracks, and the puddled field with large cracks. The rice yield in the puddle field with large cracks was 21% lower than that in the non-puddled field. The percentage of whole grains in the puddled field with large cracks was notably lower than that in the puddled field with small cracks and the non-puddled field. Moreover, the percentage of white as well as cracked rice kernels was remarkably higher in the puddled field with large cracks. These results suggest that the presence of large cracks in a puddled field decreases both plant water uptake and the quality and quantity of rice yield.