Pemberian Kalium Pada Perlakuan Cekaman Lengas :Pengaruhnya Terhadap Perubahan Ultrastruktur Bintil Akar Tanaman Clover Putih(Trifollium repens L)
| Main Author: | Perpustakaan UGM, i-lib |
|---|---|
| Format: | Article NonPeerReviewed |
| Terbitan: |
[Yogyakarta] : Universitas Gadjah Mada
, 1997
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| Subjects: | |
| Online Access: |
https://repository.ugm.ac.id/22818/ http://i-lib.ugm.ac.id/jurnal/download.php?dataId=5742 |
Daftar Isi:
- ABSTRACT Experiments conducted under controlled conditions on white clover (Trifolium repens L.) were intended to study the effect of water stress on the histological structures of root nodules and its restoration capacity, and to know the role of potassium in reducing the effect of water stress. The experiments were done under a rhizotron and a hydroponical culture in growth chamber. During the period of plant growth, the water content of soil in rhizotron was maintained at 80% of field capacity. Water stress was then induced by withholding the water supply and maintaining the soil water content at different level of field capacity (20, 40, 80 %). As a control used under saturated water. After 7 days of deficit conditions, all of the treated plants were rehydrated to 80 % of field capacity. The other experiment was condudted under potential osmotic resulted from polythylene glycole (0 and 20 % W/V PEG 6000). The mineral nutrition in the form of potassium chloride was also added at the rate of 0.005 and 5.0 mM KCI. Results of the experiment showed that water stress induced the changes in the histological structures of root nodules of white clover, i.e.: increasing the senescence and degeneration of bacteroids, and also resulted in accumulation of polysaccharide content in bacteroid fixatrice region. However, the polysaccharide content in the senescence region was reduced. Application of potassium could stabilize the water economy that beneficial in maintaining the N fixation and minimize the degeneration of bacteroids in bacteroid fixatrice region. After rehumidification, the nodules were able to improve considerably their structures. Restoration of the function of new bacteroid fixatrice was observed. Key words : White clover (Trifolium repens L.), hydroponical cultrue, rhizotrons, water stress, potassium, ultrastructure, polysaccharides, PAS. INTISARI Penelitian dilakukan di ruangan dengan faktor lingkungan terkendali (Ecotron), yang bertujuan untuk meneliti pengaruh cekaman lengas terhadap ultrastruktur bintil akar tanaman clover putih (Trifolium repens L.), dan kemampuan merestorasi setelah diairi kembali, serta untuk mengetahui peranan kaliurn dalam membatasi pengaruh cekaman lengas rendah terhadap tanaman. Penelitian ini menggunakan tanah dalam rhizotron dan dengan media hidroponik. Selama pertumbuhan tanaman awal, kandungan lengas tanah dipertahankan sampai 80 persen kapasitas lapangan. Perlakuan kandungan lengas tanah yang berbeda dengan cara menghentikan pengairan, dan kemudian kandungan lengas tanah tersebut dipertahankan dengan berbagai aras yaitu 20, 40, 60 dan 80 persen kapasitas lapangan. Sebagai kontrol digunakan tanaman yang diairi setiap hari dengan kondisi jenuh air. Setelah tanaman mengalami cekaman lengas selama sate minggu kemudian seluruh perlakuan diberi pengairan kembali sampai aras 80 persen kapasitas lapangan. Penelitian paralel dengan menggunakan media hidroponik. Cekaman lengas terjadi sebagai akibat cekaman osmotik, yaitu dengan cara memberikan larutan polyetheIene glycole (konsentrasi larutan 0 dan 20% w/v PEG 6000) ke dalam larutan makanan. Hara mineral kalium ditambahkan kedalam larutan makanan WCH dengan konsentrasi 0,005 dan 5,0 mM KCI.