[Effect of organic fertilizers and arbuscular mycorrizal fungi application on community of rhizosphere microorganism, mycorrhizal colonization growth and yield of corn on ultisols].

English. An experiment to study the effect of organic fertilizers and arbuscular mycorrhizal fungi (AMF) application on community of rhizosphere microorganism, mycorrhizal colonization, growth and yield of corn on Ultisols was carried out in green house, Faculty of Agriculture, UNPAD, from July to October 2002. The experiment used Randomized Block Design, as treatmens were: without organic fertilizers and AMF (A)without AMF and 2.5 cc/l of liquid organic fertilizer (B)without AMF and 5 cc/l of liquid organic fertilizer (C)without AMF and 25 g/plant of casting (D)without AMF and 50 g/plant of casting (E)with AMF and without organic fertilizers (F)with AMF and 2.5 cc/l of liquid organic fertilizers (G)with AMF and 5 cc/l of liquid organic fertilizers (H)with AMF and 25 g/plant of casting (I)with AMF and 50 g/plant of casting (J). The experiment consisted of two units with three replicationsthe first unit was harvested in the end of vegetative period to observe population of soil bacteria, mycorrhizal infection, dry weight of shoot and root and the second unit was harvested in the end of generative period to find out the yield of corn. The results of this experiment showed that organic fertilizers and arbuscular mycorrhizal fungi (AMF) application were significant effect on degree of mycorrhizal infection, population of soil bacteria, dry weight of root, plant height (two weeks after planting) and the yield of corn, while that were non significant effect on dry weight of shoot and plant height (four and six weeks after planting). Casting was better than liquid organic fertilizers on degree of mycorrhizal infection, population of soil bacteria, dry weight of shoot and root and plant height.

English. Penelitian ini bertujuan untuk mengetahui pengaruh pemberian pupuk organik dan aplikasi cendawan mikoriza terhadap populasi mikroba di rhizosfer kolonisasi mikoriza, pertumbuhan dan hasil tanaman jagung pada Ultisols telah dilakukan di rumah kaca Fakultas Pertanian UNPAD sejak bulan Juli sampai dengan Oktober 2002. Penelitian menggunakan rancangan acak kelompok dengan perlakuan sebagai berikut: A = tanpa mikoriza, tanpa pupuk organikB = tanpa mikoriza, pupuk organik cair 2,5 cc/lC = tanpa mikoriza, pupuk organik cair 5 cc/lD = tanpa mikoriza, kascing 25 g/tanamanE = tanpa mikoriza, kascing 50 g/tanamanF = inokulasi mikoriza tanpa pupuk organikG = inokulasi mikoriza pupuk organik cair 2,5 cc/lH = inokulasi mikoriza, pupuk organik cair 5 cc/lI = inokulasi mikoriza, kascing 25 g/tanamanJ = inokulasi mikoriza, kascing 50 g/tanaman. Percobaan diulang tiga kali dan terdiri dari dua unit percobaan, satu unit untuk pengamatan sampai fase vegetatif akhir yaitu populasi total bakteri tanah, derajat infeksi akar, berat kering tanaman dan berat kering akar, selanjutnya unit yang kedua untuk pengamatan hasil tanaman jagung (panen). Hasil penelitian menunjukkan pemberian pupuk organik cair dan kascing serta aplikasi CMA berpengaruh nyata terhadap derajat infeksi akar, populasi total bakteri tanah, berat kering akar, tinggi tanaman pada 2 MST serta hasil tanaman jagung, sedangkan pada 4 dan 6 MST. tidak memberikan pengaruh yang nyata terhadap berat kering tanaman dan tinggi tanaman. Perlakuan kascing lebih baik dibandingkan dengan pupuk organik cair terhadap derajat infeksi akar, populasi total bakteri tanah, berat kering akar, berat kering tanaman serta tinggi tanaman.