Nutritional disorders in rice due to infestation by Heterodera oryzicola and Meloidogyne graminicola.
Infestation of rice by H. oryzicola and M. graminicola caused a reduction in nitrogen, phosphorus, iron and reducing sugars in the shoots and roots. Total sugars, protein, IAA, cytokinin and thiamine were reduced in the H. oryzicola-infested plants, and phenols were reduced in the M. graminicola-infested plants. Phenols decreased in the shoots and increased in the roots due to H. oryzicola, while M. graminicola caused similar changes in potassium, manganese and magnesium. There was an increase in calcium, sodium, soluble amino-acids, ABA and starch in both the shoots and roots of the H. oryzicola-infested plants and of total sugars, protein, DNA and RNA in the M. graminicola-infested plants. Infestation by both the nematodes caused nutritional disorders limiting the uptake of nitrogen and phosphorus, and chlorosis of leaves.