PENGARUH INOKULASI MIKORIZA ARBUSKULA TERHADAP PERTUMBUHAN DAN HASIL KEDELAI (Glycine max (L.) Merrill) PADA BERBAGAI INTERVAL PENYIRAMAN

ASMARY MUIS, Prof. Dr. Ir. Didik Indradewa, Dip. Agr. St.

2013 | Skripsi | AGRONOMI

Pada umumnya kedelai ditanam di sawah dan tegalan (lahan kering). Kedua jenis lahan ini berpotensi mengalami keterbatasan air. Kekurangan air dapat menghambat pertumbuhan tanaman dan menurunkan hasil. Aplikasi mikoriza pada tanaman merupakan salah satu upaya untuk mengatasi terhambatnya pertumbuhan karena cekaman kekeringan. Penelitian bertujuan untuk mengetahui pengaruh inokulasi mikoriza arbuskula terhadap pertumbuhan dan hasil kedelai pada kondisi air yang terbatas. Penelitian dilaksanakan di rumah kaca Kebun Percobaan Fakultas Pertanian Universitas Gadjah Mada, Banguntapan, Bantul, Yogyakarta dari bulan Juni hingga September 2012. Penelitian menggunakan Rancangan Acak Lengkap 2 faktor. Faktor pertama dengan 2 aras mikoriza yaitu tanpa inokulasi mikoriza dan inokulasi mikoriza. Faktor kedua dengan 3 aras interval penyiraman antara lain setiap hari, 3 hari, dan 6 hari. Inokulasi mikoriza dilakukan sebelum benih ditanam sedangkan perbedaan interval penyiraman setelah tanaman berumur 4 mst. Kadar lengas tanah diamati sebelum dan setelah penyiraman. Infeksi mikoriza pada akar, kadar prolin, dan kadar klorofil diamati pada vegetatif maksimum. Pengamatan terhadap sistem perakaran dan tajuk pada 4 mst, 8 mst, dan saat panen serta pengamatan komponen hasil dan hasil tanaman. Hasil penelitian menunjukkan tidak terdapat interaksi antara mikoriza dengan interval penyiraman padasemua parameter pengamatan kecuali pada luas permukaan akar tanaman saat panen. Inokulasi mikoriza dapat meningkatkan luas permukaan akar tanaman kedelai pada kondisi air yang terbatas namun tidak meningkatkan komponen hasil dan hasil tanaman kedelai. Peningkatan interval penyiraman menjadi 6 hari sekali menurunkan kadar lengas tanah, menghambat pertumbuhan akar dan tajuk, menurunkan bobot kering total serta komponen hasil dan hasil tanaman.

Generally soybeans grown in field and dry land. Both of them could suffered water deficient. Water deficient could inhibit plant growth and decrease crop yield. Mycorrhizal inoculation in plants was one way to overcome growth inhibiton because of drought stress. The objective of this research was to study the effect of arbuscula mycorrhizal inoculation on the growth and yield of soybean under limited water conditions. The experiment was conducted in green house at the experimental field of Agriculture Faculty Gadjah Mada University, Banguntapan, Bantul, Yogyakarta from June until September 2012. The treatments were arranged in 2 x 3 factorial completely randomized design. The first treatment factor was mycorrhizal consisted of uninoculated and inoculated by arbuscula mycorrhizal. The second treatment factor was watering intervals consisted of every day, 3 days, and 6 days. Mycorrhizal was inoculated before the seeds were planted and various watering intervals begun 4 weeks after planting. Soil moisture level was measured before and after watering. Percentage of mycorrhizal infection at root, relative water content, proline, and chlorophyll were observed at vegetative maximum. Root system and shoot were observed after 4 weeks, 8 weeks, and when it was harvesting and also yield components and yield of soybean. The results showed that there was no interaction between mycorrhizal and intervals watering at all models except at root surface when it was harvesting. Mycorrhizal inoculation increased root surface area under limited water conditions and did not increase yield components and yield of soybean. Increasing of watering intervals up to 6 days reduced soil moisture, inhibited the growth of root and shoot, decreased total biomass, yield components and yield of soybean.

Kata Kunci : mikoriza arbuskula, kedelai, interval penyiraman