Penentuan Tingkat Kemasakan, Periode After ripening, dan Vigor Daya Simpan Benih Padi Gogo pada beberapa Dosis Pupuk Fosfat

Abstract

Luas panen padi terus mengalami penurunan seiring dengan meningkatnya alih fungsi lahan sawah. Padi gogo menjadi salah satu alternatif solusi mengatasi permasalahan tersebut sehingga memerlukan ketersediaan benih padi gogo yang bermutu tinggi. Tujuan penelitian adalah menentukan dosis pupuk P yang tepat, umur masak fisiologi benih, lama periode after ripening, dan daya simpan benih padi gogo varietas IPB 10G Tanimar. Penelitian disusun menggunakan rancangan acak kelompok split plot dua faktor dengan tiga ulangan. Petak utama adalah dosis pupuk yaitu 50, 100, dan 150 kg ha-1 SP36 sedangkan anak petak adalah tingkat masak yaitu 112 , 116, 120, 124, dan 128 hari setelah tanam (HST). Hasil penelitian menunjukkan bahwa dosis pupuk fosfat tidak berpengaruh terhadap pertumbuhan vegetatif dan generatif. Perlakuan dosis pupuk 100 kg ha-1 SP36 menghasilkan mutu benih terbaik berdasarkan indeks vigor setelah panen. Tingkat masak terbaik adalah 124 HST menurut indeks vigor saat panen dan viabilitas benih selama penyimpanan (daya berkecambah, indeks vigor, potensi tumbuh maksimum, kecepatan tumbuh, berat kering kecambah normal, dan daya hantar listrik), serta vigor daya simpan berdasarkan nilai indeks vigor setelah perlakuan pengusangan cepat. Pada beberapa parameter viabilitas benih (daya berkecambah, indeks vigor, potensi tumbuh maksimum, kecepatan tumbuh, dan berat kering kecambah normal) pada minggu tertentu penyimpanan benih, tingkat masak 120 HST dan 124 HST sama sehingga panen dapat dilakukan pada rentang 120 – 124 HST. Periode after ripening terpendek 1 minggu setelah simpan adalah benih yang dipanen 124 HST. Benih padi varietas IPB 10G Tanimar memerlukan satuan panas 2.428,15 ?Cd – 2.505,15 ?Cd untuk panen calon benih yang optimum.

Rice harvest area continues to decline in line with increasing conversion of rice fields. Upland rice has become one of the alternative solutions to overcome this problem, thus requiring the availability of high-quality upland rice seeds. The objectives of this study were to determine the appropriate P fertilizer dose, physiological maturity of seeds, length of the after ripening period, and seed storage life of IPB 10G Tanimar upland rice variety. The study was designed using a two-factor split-plot randomized block design with three replications. The main plot was the fertilizer dose, namely 50, 100, and 150 kg ha-1 SP36, while the subplot was the maturity level, namely 112, 116, 120, 124, and 128 days after planting (DAP). The results showed that the phosphate fertilizer dose had no effect on vegetative and generative growth. The 100 kg ha-1 SP36 fertilizer dose treatment produced the best seed quality based on the vigor index after harvest. The optimum maturity level was 124 DAP based on the vigor index at harvest and seed viability during storage (germination percentage, vigor index, maximum growth potential, growth rate, normal seedling dry weight, and electrical conductivity), as well as storage vigor determined by the vigor index after accelerated aging treatment. For several seed viability parameters (germination percentage, vigor index, maximum growth potential, growth rate, and normal seedling dry weight) at certain weeks of seed storage, the maturity levels of 120 DAP and 124 DAP were similar therefore, harvesting can be conducted within the range of 120–124 DAP. The shortest after-ripening period of 1 week after storage was for seeds harvested at 124 HST. IPB 10G Tanimar rice seeds require 2,428.15–2,505.15 °Cd heat units for optimal seed harvesting.