Effects Of Calcium Fertilization On Plant Morphological And Physiological Traits,Yield And Tuber Quality Of Potato Of "Kexin18"

Calcium is important micronutrient in the growth and development of potato.The demand for calcium in potato is not much, but necessary.The plant can not grow normally in the case of calcium deficiency. But excessive calcium fertilization is toxic to plant. The influence of exogenous calcium on potato morphological traits, yield component, quality of calcium content in tuber were studied in this study by the two factors randomized block design using “Kexin18”variety as material. The trial was made in the field in the condition of different nitrogen levels. The result shows as follows:(1)Exogenous calcium could increase plant height and stem diameter significantly, the optimal level of exogenous calcium was between 57kg/hm2 and 114kg/hm2. The plant height and stem diameter increase with the adding of nitrogen level. So Nitrogen fertilizer could promote the growth of plant over the ground part. There was no interaction effect on the plant height and stem diameter in calcium and nitrogen.(2) Exogenous calcium could be conductive to raise net photosynthetic traits. The content of chlorophyll a, chlorophyll b increase significantly between 57kg/hm2 and 114kg/hm2, and represent best in the 57kg/hm2 caicium level.In Pn aspect, when the concentration of calcium was57kg/hm2,variation of Pn reached a maximum,and significantly higher than the level of without exogenous calcium.From above factors, the nitrogen level of 150 kg/hm2 is best.(3) Exogenous calcium could enhance the ability of plant resistent,reduce the accumulation of MDA in leaf.The content of MDA can reflect the ability of plant resistant,the less MDA it accumutes, the ability of resisting outside stress is stronger.In this study, the content of MDA in different exogenous calcium treatments was less than the content without exogenous calcium.(4)From the character of calcium absorbing of potato,we could suggest that tuber bulking stage is the most important period to absorb calcium for potato.In this period supplement potato with calcium could effectively improve the calcium level in tuber.(5)The yield of commodity potato, commodity tuber number per plant and commodity tuber rate in tuber were improved significantly in a certain range with the increasing of exogenous calcium,the yield of commodity potato increase significantly between the exogenous calcium level of 57kg/hm2 and 114kg/hm2,and the yield of commodity potato reached highest in the exogenous calcium level of 57kg/hm2. In nitrogen aspect,there was interaction effect in calcium and nitrogen,and the the optimal level of nitrogen is 150 kg/hm2.(6) Calcium fertilization could significantly improve the caicium content and the quality of tuber.The calcium content was improved with the increasing of exogenous calcium in the whole,in the exogenous calcium level of 171 kg/hm2 the calcium content in tuber reach the highest, but in228 kg/hm2 level the calcium content was decreased a little.this result show that supplement potato tuber with calcium an effectively improve the calcium level in tuber.(7)Exogenous calcium could significant decrease tuber physiological disease rate of tuber.the rate of tuber disease was lowest between 57kg/hm2 and 114kg/hm2.