Improving the Facility Soil by Combining Soil Amendment with Agronomic Measures

[Objectives]To study the remediation methods of secondary salinization and cadmium pollution in facility soil.[Methods]Two kinds of soil amendments,potassium fulvic acid and limestone powder,were selected to be applied alone or combined together to plant maize to carry out field experiments.Their effects on watermelon yield,watermelon cadmium content,soil available nitrogen,phosphorus,potassium and water-soluble salts were studied.[Results]The application of potassium fulvic acid,limestone powder and their combined application increased the yield and soluble solids of watermelon to different degrees.The contents of seven heavy metals including cadmium,copper,zinc,arsenic,lead,mercury and chromium in the watermelon of all treatments were all lower than the food safety limit stipulated in the national standard.During the harvest period of maize seedlings,all treatments could increase soil pH and decrease soil cadmium availability.In particular,3000 kg/ha of limestone powder and 1500 kg/ha of potassium fulvic acid had the best effect on reducing soil available cadmium content.In reducing soil available cadmium content,there were significant differences between single application of amendment and combined application treatments.In addition,compared with the control CK,all treatments decreased soil available nitrogen,phosphorus,potassium and water-soluble salt content.[Conclusions]Potassium fulvic acid,limestone powder and their combined application can increase the yield of watermelon,and can significantly reduce the available cadmium,nitrogen,phosphorus,potassium and water-soluble salt content in the facility soil of maize cultivation.

Agronomic cultivation measures on productivity of oilseed flax:A review

Oilseed flax is one of the most important oil crops in China.With the improvement of people's living standards and the deepening knowledge of the nutritional value of oilseed flax,the demand and economic value of oilseed flax are increasing,and the cultivated area in China is expanding.However,the grain yield of oilseed flax is lower than other oil crops.It varies significantly from year to year,combined with a lower degree of mechanization,which has greatly limited the healthy development of the flax industry.Some of the effects of agronomic measures on productivity and water use efficiency of oilseed flax are reviewed in this paper.The major agronomic strategies for the productivity of oilseed flax were presented based on fertilization,plant density,irrigation,cropping pattern and weed control.Future research should investigate the effect of silicon and potassium fertilizers on the mechanism of lodging resistance of oilseed flax,the effects of diversified cropping systems(strip intercropping and crop rotation)on high and stable productivity and efficient utilization of resources.

Waterlogging stress in cotton:Damage, adaptability, alleviation strategies, and mechanisms

Over the last few decades,waterlogging stress has increasingly threatened global cotton production.Waterlogging results in reduced soil oxygen,impairing the growth and development of this valuable crop and often resulting in severe yield loss or crop failure.However,as cotton has an indeterminate growth habit,it is able to adapt to waterlogging stress by activating three mechanisms:the escape,quiescence,and self-regulating compensation mechanisms.The escape mechanism includes accelerated growth,formation of adventitious roots,and production of aerenchyma.The quiescence mechanism involves reduced biomass accumulation and energy dissipation via physiological,biochemical,and molecular events.The self-regulation compensation mechanism allows plants to exploit their indeterminate growth habit and compensatory growth ability by accelerating growth and development following relief from waterlogging stress.We review how the growth and development of cotton is impaired by waterlogging,focusing on the three strategies associated with tolerance and adaptation to the stress.We discuss agronomic measures and prospects for mitigating the adverse effects of waterlogging stress.