高温胁迫对芹菜幼苗生长及生理指标的影响

根据多年夏季露地自然高温下的观察和35℃高温胁迫下的热害指数,通过实验筛选出了不同耐热性的7个品系;进一步在20℃/12℃(d/n)(CK)、26℃/20℃(d/n)、30℃/20℃(d/n)人工模拟高温胁迫条件下,测定了这7个品系的幼苗生长量、游离蛋白质含量、以及可溶性总糖含量。结果表明:在26℃/20℃(d/n)和30℃/20℃(d/n)高温胁迫下,相对生长量、株高相对增长量、游离蛋白质相对含量和可溶性总糖的相对含量品系间差异显著;对热害指数第96小时的值、30/20℃鲜重生长量的相对增加值、26/16℃干重生长量的相对增加值、30/20℃株高的相对增长量、26℃/16℃(d/n)处理下游离蛋白质和26℃/16℃(d/n)可溶性总糖相对含量的试验数据采用隶属函数法对品系的耐热性进行综合评价,与多年田间观察结果比较一致。进一步对各单项指标与隶属函数值进行相关性分析,其中热害指数、26℃/16℃下的干、鲜重相对生长量和30/20℃下干重的相对生长量都和耐热性有显著和极显著相关性,可以作为鉴定芹菜耐热性的指标。

Effect of Long-term Rotated Fertilization on Dynamic Change of Potassium in Brown Soil

The influence on the dynamic change of the brown soil K when soybean and maize are cropped by rotation is researched through 25 years long-term localization experiment. The result indicates: in each processing the change tendency of content of available potassium and slow release potassium for the soybean year all disappears to be larger than that for the maize year(1992>1993year,2002>2003year),the content of mineral potassium for the soybean year is less than that for the maize year. When CK,N1 and N1P three disposal are not fertilized with K chronically in soil various shapes K all assumes year by year drops, the drop scope of available and slow release potassium for the maize year is quicker than that for the soybean year, the mineral potassium for the maize year is slower than that for the soybean year. For a long-term executing the K in each processing the content of available potassium assumes rise tendency year by year; the content of slow release potassium assumes drop tendency year by year from 1992; the content of mineral potassium assumes rise tendency for maize year and drop tendency for soybean year. Four years related statistical analysis indicates correlation notability is invariable along with between the planting fixed number of years increase between soil available and slow release potassium.