This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice （Oryza sativa L.）. Pot trials and cylinder trials were carried out from 2002 to 2005...This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice （Oryza sativa L.）. Pot trials and cylinder trials were carried out from 2002 to 2005 to study the influences of single basal application of 3 controlled-release fertilizers on the changes of soil available N, root development, senescence and lodging resistance at late growth stages. Results showed that at 30 days after fertilization, single basal application of controlled-release fertilizers coated with vegetal-substance （CRF1） and polymer materials （CRF3） increased soil available N to 12.0 and 147.9%, respectively, in comparison to split fertilization of rice-specific fertilizer （RSF1）. Treatments of the two CRFs obviously benefited the development of root system, resulting in greater rice root weights with extensive distribution and higher root activity. In addition, the two CRF treatments, in comparison to RSF1, enhanced chlorophyll consents of the flag leaves to 9.5 and 15.5%, and soluble protein up to 89.7 and 108.0% respectively. Application of the two CRFs also made the base of rice stems strong and large, declined the proportion of shoot and root, increased root depth index. Though relatively low K rate, single basal application of the CRF3 coated with NH4MgPO4 could also promote the development of root system, enhance root activity and some physiological functions of flag leaves. Based on these results, it was concluded that major mechanisms for increasing rice yield by single basal application of the CRFs should be attributed to grater soil available N supply, superior development of root systems, better nutrient absorption capacity, slower senescence and enhancement of lodging resistance at late stages.展开更多
Background: Characterisation of cotton-based cropping systems is essential for understanding and improving cotton production in Côte d’Ivoire. The aim of this study was to determine the effects of cropping pract...Background: Characterisation of cotton-based cropping systems is essential for understanding and improving cotton production in Côte d’Ivoire. The aim of this study was to determine the effects of cropping practices on seed cotton yields. A survey of a network of 600 growers in all the cotton-growing areas was carried out to gather information on the type of soil preparation (manual, harnessed and motorised), the sowing decade, the previous crop, the cotton variety, the sowing density, the date of fertilizer application (NPK and urea), the number of weeding operations, the number of insecticide treatments and, finally, the seedcotton yield. Results: The results showed that during the last cotton season (2023-2024), the sowing decades, crop precedents and a number of insecticide treatments had a highly significant effect on yield. Sowing in the first, second and third decade of June (1 to 10 June, 11 to 20 June and 21 to 30 June respectively). In addition, the best yields were obtained by growers who applied NPKSB base fertilizer and cover fertilizer (urea) within the sowing period at 10 days before sowing (0 - 10 days before sowing) and 45 - 60 days before sowing, respectively. In addition, better yields of close to 2 tons per hectare (1725 kg/ha) were observed among growers who applied a dozen insecticide treatments (eleven more than the six recommended by the research and development services). Conclusion: Further analysis will be carried out, taking into account parameters such as plot size, fertilizer doses (NPK and urea), climatic parameters (rainfall and temperature), agro-ecological zones and the physico-chemical parameters of the growers’ soils. With this in mind, the Ivorian cotton companies will be able to provide farmers with a decision-making tool to help them monitor cultivation operations and improve farm performance.展开更多
文摘This paper was to explore the mechanism of single basal application of controlled-release fertilizers for increasing yield of rice （Oryza sativa L.）. Pot trials and cylinder trials were carried out from 2002 to 2005 to study the influences of single basal application of 3 controlled-release fertilizers on the changes of soil available N, root development, senescence and lodging resistance at late growth stages. Results showed that at 30 days after fertilization, single basal application of controlled-release fertilizers coated with vegetal-substance （CRF1） and polymer materials （CRF3） increased soil available N to 12.0 and 147.9%, respectively, in comparison to split fertilization of rice-specific fertilizer （RSF1）. Treatments of the two CRFs obviously benefited the development of root system, resulting in greater rice root weights with extensive distribution and higher root activity. In addition, the two CRF treatments, in comparison to RSF1, enhanced chlorophyll consents of the flag leaves to 9.5 and 15.5%, and soluble protein up to 89.7 and 108.0% respectively. Application of the two CRFs also made the base of rice stems strong and large, declined the proportion of shoot and root, increased root depth index. Though relatively low K rate, single basal application of the CRF3 coated with NH4MgPO4 could also promote the development of root system, enhance root activity and some physiological functions of flag leaves. Based on these results, it was concluded that major mechanisms for increasing rice yield by single basal application of the CRFs should be attributed to grater soil available N supply, superior development of root systems, better nutrient absorption capacity, slower senescence and enhancement of lodging resistance at late stages.
文摘Background: Characterisation of cotton-based cropping systems is essential for understanding and improving cotton production in Côte d’Ivoire. The aim of this study was to determine the effects of cropping practices on seed cotton yields. A survey of a network of 600 growers in all the cotton-growing areas was carried out to gather information on the type of soil preparation (manual, harnessed and motorised), the sowing decade, the previous crop, the cotton variety, the sowing density, the date of fertilizer application (NPK and urea), the number of weeding operations, the number of insecticide treatments and, finally, the seedcotton yield. Results: The results showed that during the last cotton season (2023-2024), the sowing decades, crop precedents and a number of insecticide treatments had a highly significant effect on yield. Sowing in the first, second and third decade of June (1 to 10 June, 11 to 20 June and 21 to 30 June respectively). In addition, the best yields were obtained by growers who applied NPKSB base fertilizer and cover fertilizer (urea) within the sowing period at 10 days before sowing (0 - 10 days before sowing) and 45 - 60 days before sowing, respectively. In addition, better yields of close to 2 tons per hectare (1725 kg/ha) were observed among growers who applied a dozen insecticide treatments (eleven more than the six recommended by the research and development services). Conclusion: Further analysis will be carried out, taking into account parameters such as plot size, fertilizer doses (NPK and urea), climatic parameters (rainfall and temperature), agro-ecological zones and the physico-chemical parameters of the growers’ soils. With this in mind, the Ivorian cotton companies will be able to provide farmers with a decision-making tool to help them monitor cultivation operations and improve farm performance.
