土壤施氮量对‘温185’核桃根系基础呼吸速率的影响

Effects of Different Nitrogen Fertilizer Application on Root Basic Respiration Rate of Juglans regia ‘Wen 185’

以新疆南疆盆地核桃主栽品种‘温185’(Juglans regia‘Wen 185’)为供试材料,基于田间土壤氮(N)肥施肥试验,利用Oxytherm液相氧测定系统,测定氮肥不同施用量条件下核桃花后不同时节(果实不同生育时期)根系基础呼吸速率,分析氮肥施用量和花后时间对核桃根系基础呼吸速率的影响。结果表明:‘温185’核桃根系基础呼吸速率的自然对数(lnY)与花后时间(T)及花后时间的自乘(T×T或T^2)、氮肥施用量(纯N量,N)及氮肥施用量的自乘(N×N或N^2)存在极显著线性相关关系;花后时间对核桃根系基础呼吸速率存在负效应,氮肥施用量对核桃根系基础呼吸速率的影响与根系直径相关。当单株施氮量小于0.4976 kg时,不同直径大小根系的基础呼吸速率均随施氮量的增加而升高。

Using adominant walnut variety in southern Xinjiang basin,‘Wen 185’as the material,the field nitrogen fertilization experiment was carried out.The root basic respiration rate of walnut at different post-flowering seasons(fruits at different growth stages)under different N fertilization conditions was determined with Oxytherm liquid phase oxygen analysis system and analyze the effects of N fertilization amount on the basic respiration rate of walnut root during post flowering days.The results showed that the natural logarithm(ln Y)of root basic respiration rate of‘Wen 185’walnut had a very significant linear correlation with the post-anthesis time(T),the square of post-anthesis time(T×T or T^2),the amount of nitrogen fertilizer(pure N,N),and the square of nitrogen fertilizer(N×N or N^2).Root respiration rate decreased after anthesis,and the effect of N fertilization on the root respiration rate was related to root diameter.When N application amount was less than 0.5698 kg per tree,the basal respiration rate of root system increased with the increase of N application.Thus,appropriate nitrogen fertilization should be determined according to soil N nutrient status in the fertilization management of‘Wen 185’walnut production in south Xinjiang basin.