Studies on the absorption of nutrient elements in muskmelon. III

Abstract

The purposes of the present study were to in-vestigate the effect of nitrogen and calcium forms on the fruit quality and the absorption of nutritional elements in muskmelon. The levels of calcium were also investigated. Plants of the variety Earl's Favourite were grown by the method reported in the previous paper. Details of the design of ferti-lizer treatment are presented in Table 1. The re-sults obtained are presented in Tables 2 to 7, inclu-sive. 1. The main effects of increasing the level of calcium were to promote the vigorous growth, to increase the leaf, stem and fruit weights, to im-prove the external appearance, to increase the pH value of soil, to increase the nitrogen, phosphorus. calcium and magnesium amounts in the whole plant, to increase the percentage of calcium in various organs of the plant, and to decrease the percentage of nitrogen in leaves, stem and roots. 2. The main effects of nitrogen form were: NO3-N form increased the fruit weight, increased the pH value of soil, inhibited the vigorous growth, decreas-ed the nitrogen and potassium amounts in the whole plant, increased the calcium amount in the whole plant, and decreased the percentage of nitro-gen in various organs of the plant. 3. The main effects of calcium form were: CaCO3 form increased the nitrogen, phophorus, potassium and calcium amounts in roots. 4. Some interactions were obtained from the variables. 5. No significant effects were shown by any of the nitrogen and calcium forms on the growth and fruit quality. 6. The plants which received 40 to 80g CaO per plant were able to maintain vigorous growth and produced fruits of high quality. Judging from these results, the recommendable amount of calcium application is 40 to 80g per plant. 7. The amounts of N, P2O5, K2O, CaO and MgO in the whole plants resulting from receiving 40 to 80g calcium were 4.8 to 4.9, 2.4 to 2.5, 8.7 to 8.9, 10.1 to 10.7 and 1.6 to 1.7 g per plant, respec-tively.