钙镁缺乏对不同甘薯品种的生长及矿质元素吸收的影响

为了探索钙、镁元素缺乏对不同甘薯品种的生长及矿质元素吸收的影响,采用砂培的方法,以苏16和苏11为材料,在钙、镁缺乏条件下,对其外观症状、叶绿素含量、光合作用、地上与地下部分生物量及其根部和叶部矿质元素含量进行了研究。结果表明:钙、镁缺乏时苏16和苏11的叶绿素含量、净光合速率、地上和地下生物量均显著下降,苏11的下降幅度比苏16大,缺钙条件下,苏16的显著症状为烂根,并且只有根部和叶部的钙含量显著下降(P0.05),苏11的典型症状为老叶坏死的斑块沿着靠近叶柄的叶边缘不规则向外扩散,逐渐衰老枯落,并且根部钙含量显著降低伴随铁的显著降低(P0.05),可能伴有缺铁并发症,缺镁条件下,苏16和苏11的典型症状相同,叶片均失绿,老叶逐渐枯萎脱落,并且根部和叶部的镁含量显著降低伴随着硫含量的显著降低(P0.05),可能伴有缺硫并发症。

The influence of calcium and magnesium deficiency on growth and mineral elements absorption of different sweetpotato varieties

In order to explore the influence of calcium and magnesium deficiency on growth and mineral elements absorption of different sweetpotato varieties,the method of sand culture was adopted.The symptoms appearance,chlorophyll content,photosynthesis,the ground and underground biomass,root and leaf mineral element content of Su16 and Su11 were studied under the condition of calcium and magnesium deficiency.The results showed that chlorophyll content,net photosynthetic rate,the ground and underground biomass of Su16 and Su11 were decreased significantly under calcium and magnesium deficiency,but Su11 declined more than Su16.Moreover,under the condition of calcium deficiency,Su16 appeared typical symptoms of rotten root,and the calcium content of Su16 in root and leaf decreased significantly(P<0.05),while Su11 appeared typical symptoms that necrotic patches in old leaves near petiole spread irregularly beyond the leaf edge,then gradually withered and fell.The calcium content of Su11 in root decreased significantly with iron content decreasing significantly(P<0.05).It was suggesting that calcium deficiency might be associated with iron deficiency.Under magnesium deficiency condition,typical symptom of Su16 and Su11 was the same,for both of them the leaves became yellow and the old leaves fell and withered gradually.Under magnesium deficiency,the magnesium content of roots and leaves decreased significantly with sulfur content decreasing significantly(P<0.05).It was suggesting that magnesium deficiency might be associated with sulfur deficiency.