Penentuan Tingkat Masak Fisiologis dan Efektivitas Seed Coating dalam Meningkatkan Daya Simpan Benih Pisang Liar Musa acuminata var. rutilifes

Abstract

Tanaman pisang terbagi menjadi pisang budidaya (tanpa biji) dan pisang liar (berbiji), salah satunya Musa acuminata var. rutilifes yang masih minim informasi di Indonesia. Keragaman plasma nutfah pisang liar ini penting dijaga melalui konservasi dan pengembangan lebih lanjut. Upaya pelestarian dapat dilakukan dengan karakterisasi benih, dimana mutu fisiologis benih sangat dipengaruhi oleh tingkat masak saat panen yang menentukan mutu awal sekaligus daya simpan. Penyimpanan benih merupakan strategi penting untuk menjaga mutu fisiologis dan konservasi genetik, meskipun tingkat masak fisiologis berbeda antar komoditas, aksesi, maupun varietas. Salah satu inovasi yang relevan untuk konservasi adalah penerapan teknologi seed coating yang berfungsi sebagai lapisan protektif dalam penyimpanan sekaligus media penghantar zat pengatur tumbuh. Penelitian ini bertujuan untuk menentukan masak fisiologis benih pisang liar Musa acuminata var. rutilifes berdasarkan karakteristik buah, viabilitas, vigor, dan bobot kering benih maksimum berdasarkan hari yang tepat setelah reseptif (HSR) serta mengevaluasi efektivitas seed coating dalam meningkatkan daya simpan benih yang telah masak fisiologis. Penelitian ini dilaksanakan di Kebun Percobaan Badan Riset dan Inovasi Nasional (BRIN), Cibinong, Bogor, Jawa Barat pada bulan Februari 2025 hingga Januari 2026. Percobaan pertama disusun menggunakan rancangan kelompok lengkap teracak dengan satu faktor, yaitu umur panen yang terdiri atas lima taraf berdasarkan HSR. Percobaan kedua disusun menggunakan rancangan acak kelompok dengan rancangan tersarang (nested), melibatkan dua faktor, yaitu suhu ruang simpan sebagai faktor sarang dan seed coating serta periode simpan sebagai faktor tersarang. Hasil percobaan pertama, karakteristik buah Musa acuminata var. rutilifes berubah sesuai umur panen, dengan panjang, diameter, dan bobot buah mencapai puncak pada 90–100 HSR, sedangkan kelunakan tertinggi (7,9 mm/152,5g/5 detik) dan jumlah benih per buah terendah (59 butir) terjadi pada 130 HSR. Masak fisiologis benih dicapai pada 130 HSR dengan bobot kering benih 0,32 g, vigor 22,66%, dan viabilitas maksimum 39,33% serta hasil uji tetrazolium benih viabel 82%. Analisis korelasi menunjukkan kelunakan buah berkorelasi positif dengan mutu benih, sedangkan diameter, bobot, dan jumlah buah berkorelasi negatif. Percobaan kedua, efektivitas coating belum terbukti dapat memperpanjang daya simpan benih yang disebabkan adanya faktor penghambat akibat testa tebal yang dominan membatasi perkecambahan. Hasil SEM memperlihatkan struktur testa berlapis dan mikropil yang tebal yang menjelaskan sifat impermeabel testa.

Banana plants are classified into cultivated bananas (seedless) and wild bananas (seeded), among which Musa acuminata var. rutilifes remains poorly documented in Indonesia. Preserving the genetic diversity of these wild bananas is essential through conservation and further development. Such efforts can be undertaken via seed characterization, as the physiological quality of seeds is strongly influenced by the maturity stage at harvest, which determines both initial quality and storability. Seed storage constitutes a crucial strategy for maintaining physiological quality and genetic conservation, although the stage of physiological maturity differs among commodities, accessions, and varieties. One relevant innovation for conservation is the application of seed coating technology, which serves both as a protective layer during storage and as a medium for delivering plant growth regulators. This study aimed to determine the physiological maturity of wild banana Musa acuminata var. rutilifes seeds based on fruit characteristics, viability, vigor, and maximum seed dry weight at the appropriate days after receptivity (DAR), and to evaluate the effectiveness of seed coating in enhancing the storability of physiologically mature seeds. Experiments were conducted at the Experimental Field of the National Research and Innovation Agency (BRIN), Cibinong, Bogor, West Java, from February 2025 to January 2026. The first experiment was designed using a randomized complete block design with a single factor, harvest age, consisting of five levels based on DAR. The second experiment was designed using a randomized block design with a nested structure, involving two factors: storage room temperature as the main factor, and seed coating and storage period as the nested factors. In the first experiment, the fruit characteristics of Musa acuminata var. rutilifes varied with harvest age, with fruit length, diameter, and weight peaking at 90–100 DAR, while the greatest softness (7.9 mm/152.5 g/5 seconds) and the lowest seed number per fruit (59 seeds) were observed at 130 DAR. Physiological seed maturity was demonstrated at 130 DAR, as indicated by maximum seed dry weight of 0.32 g, vigor of 22.66%, viability of 39.33% and tetrazolium test results showing 82% viable seeds. Correlation analysis revealed that fruit softness was positively associated with seed quality, whereas fruit diameter, weight, and number were negatively associated. In the second experiment, the effectiveness of seed coating in extending seed storability was not demonstrated, due to inhibitory factors associated with the thick testa, which more dominantly restricted germination. SEM observations revealed a multilayered testa structure and a thick micropyle, which explain the testa impermeability.