The Effect of Indonesian selective cutting (TPI) on the structure and regeneration of lowland tropical dipterocarp forests in East Kalimantan, Indonesia / by Djoko Marsono

Thesis (Ph.D. - - Forest Resources Mgt.) University of the Philippines, College, Laguna.

Includes bibliographical references.

MUHADIONO, IGNATIUS. University of the Philippines at Los Banos, March 1989. Effects of Rhizobium and VA Mycorrhiza Inoculation on the Growth and Nitrogen Fixation of Albizia procera (Roxb) Benth . Under Nursery Conditions. Major Professor: Dr. Mercedes U. Garcia

Seedlings of Albizia procera (Roxb) Benth, a native species of the ASEAN region were grown under greenhouse condition for a period of three months (Studies I and II) and four months (Study. III). The effects of soil types, chemical fertilizer and biofertilizer application on seedling growth were studied. The parameters were height, diameter, nodule number, dry weight, top/root ratio, total dry matter yields, N content, N uptake, 4 N uptake, P content, P uptake and AP uptake.

The effect of Nitrogen fertilizer application was significant on height, diameter, N content and & N uptake. Inoculation with Rhizobium yielded a significant effect on height at 90 dap (days after planting); diameter at 60 and 90 dap; N content and A N uptake.

The N concentration was 20.7% better in the inoculated but fertilized with 100 kg N/ha rate than the uninoculated and fertilized with the same rate. The interaction effect between soil and N fertilizer was significant on height (90 dap), diameter (30 and 90 dap) and N content, while the interaction effect between soil and Rhizobium inoculation was shown to be significant on height (60 dap), diameter (60 and 90 dap), nodule number, total dry matter yield and N content. The interaction effect between N fertilizer and Rhizobium inoculation was significant on height (60 and 90 dap), diameter from 30 up to 90 dap and N content. Significant interaction effects among three factors, soil, nitrogen and Rhizobium inoculation was observed on height (60 and 90 dap), diameter (60 dap) and N content. The amount of nitrogen replaced by Rhizobium inoculation is estimated to be 82.5 kg N/ha of chemical nitrogen fertilizer.

Phosphorus application improved height and diameter growth, nodule number and dry matter production of A. procera (60 and 90 dap). Phosphorus application also significantly improved P content, P uptake and4P uptake of A. procera. Inoculation with Glomus etunicatum also favorably enhanced height and diameter (30 and 60 dap) and P content. The effect of the interaction between soil and P fertilizer was significant only on height and diameter growth (60 and 90 dap) and on P content. Only diameter and biomass production of the host were affected by the interaction effect of soil type and phosphorus fertilizer levels. The interaction effect of the three factors, soil, phosphorus and Gl. etunicatum inoculation
Significantly improved height (60 dap), diameter (60 and 90 dap) and P content. The phosphorus substitution by Gl. etunicatum is estimated to be 28.5 kg P,0,/ha.

The effect of nitrogen fertilizer either chemical or bioinoculant and its interaction with soil types and P application was generally not as dramatic as in the previous studies. The three factors alone or in their combinations did not produce significant effect on height of A. procera except at 30 dap. Phosphorus application improved diameter of the legume host (30 and 60 dap), dry matter yield, N uptake and 4 N uptake. Nitrogen application significantly improved diameter, biomass, N content in the tissues, N uptake, A N uptake and the P content in the tissues. The N uptake by inoculated plants was improved by 10.9% over the uninoculated plants while the A N uptake was 85.4% better than the unfertilized control. The interaction effect between phosphorus and nitrogen application generally did not improve the growth parameters except for N content, P content and 4 P uptake. The effect of dual symbiosis inoculation with Rhizobium and Gl. etunicatum shows that both 4 N and 4P uptake affected the total dry matter yield expressed as: Y = 13.97 + 29.848 X, + 742.225 X, where “Y is the total dry matter yield (g); X, is the A N uptake (g/plant) and X, is A P uptake (g/plant). TheAN uptake was highest in Annam clay soil while A P uptake was a significant determinant in Taal loam soil type. Plants grown in Annam clay had higher total dry matter yield than the plants grown in Taal sandy loam soil.

Submitted to the University Library 01/07/1994 T-1496