THE EFFECT OF ENDOMYCORRHIZAE ON THE UPTAKE OF INSOLUBLE PHOSPHATE BY ROUGH LEMON SEEDLINGS JAMBHIRI LUCH )
Tang Zhenyao Hao Kailun ( Citrus Research Institute, Chinese Academy of Agricultural Sciense, Chongqing )
Rough lemon seedlings were grown in sterilized purple soil in a pot experiment to study the effect of a vesicula:-arbuscular ( VA ) mycorrhizal fungus on the uptake of insoluble phosphate. Four treatments with three replications in each case were made as follows. 1) seedlings inoculated with an endotrophic mycorrhizal fungus ( Glomus sp. cc-1 ) ,2) fertilized with rock phosphate alone, 3) combined with above two treatments, 4) control without inoculation and applying p. Ten months after treatment, each seedling of four treatments was harvested for measuring its growth amounts and analysing plant concen-tration of P and some other mineral elements by atomic absorption spec-trocopy. Results showed that rough lemon seedlings were susceptible to this mycorrhizal fungus. The percentage of mycorrhizal infection was 96% at the end of experiment. and vesicles were commonly found in root sam-ples. During the period of the experiment. uninoculated seedlings had not been infected with mycorrhizae. Among four treatments, the treatment 3 gave the best response of vigorous growth and dry weight of plant and the largest amount of leaf area and trunk diameter. P content of whole plant increased as much as 7 times of treatment 2. There were no significant differences between treatment 2 and 4 5 seedlings of both treatments were stunting. The pre-sent study comes to the conclusion that VA mycorrhizae stimulate the absorption of insoluble phosphate by rough lemon seedling.