Respon Morfofisiologi dan Kebutuhan Air Konsumtif Tanaman Padi pada Pupuk Anorganik dan Organik

Abstract

Prioritas pembangunan pertanian untuk memenuhi kebutuhan pangan nasional semakin meningkat seiring peningkatan jumlah penduduk. Peningkatan produksi padi salah satunya dengan penggunaan pupuk anorganik, namun penggunaan yang terus menerus memicu terjadinya degradasi lahan dan air. Pupuk organik merupakan salah satu solusi untuk memperbaiki kondisi tersebut. Penelitian bertujuan untuk menganalisis perbedaan morfofisiologi dan efisiensi pemakaian air padi Inpari 33 pada pemupukan anorganik dan organik. Penelitian dilaksanakan pada bulan Juli - Desember 2020 di IP2TP Sukamandi Balai Besar Penelitian Tanaman Padi Subang Jawa Barat. Rancangan percobaan yang menggunakan Split Plot design dangan tiga ulangan. Petak utama adalah pupuk anorganik yang terdiri dari perlakuan tanpa NPK (kontrol), tanpa N (PK), tanpa K (NP), tanpa P (NK) dan NPK. Anak petak yaitu pupuk organik terdiri dari pupuk kandang sapi (pukan), kompos jerami dan tanpa organik. Hasil percobaan menunjukkan perlakuan pupuk anorganik tanpa P, tanpa K dan NPK meningkatkan pertumbuhan jumlah anakan sebesar 44-49%, nilai SPAD 6,9-10,98%, produksi 23- 51% dibandingkan perlakuan tanpa pupuk NPK dan tanpa N. Perlakuan pupuk anorganik tidak mempengaruhi laju fotosintesis namun mempengaruhi konduktansi stomata dan serapan hara. Efisiensi pemakaian air tertinggi yaitu 1,17 g gabah L-1 pada perlakuan tanpa P. Aplikasi pupuk organik belum mampu meningkatkan pertumbuhan, hasil, fotosintesis dan efisiensi penggunaan air. Konduktansi stomata dapat ditingkatkan dengan aplikasi pukan. Kebutuhan air konsumtif rata-rata tanaman padi selama penelitian adalah 469,48 mm dengan koefisien evapotranspirasi rata-rata sebesar 1,18. Interaksi pupuk anorganik dan organik mempengaruhi jumlah anakan, jumlah malai per rumpun, berat 1000 butir, serapan hara dan total evapotranspirasi. Penambahan pupuk kandang sapi sangat mempengaruhi jumlah anakan dan total evapotranspirasi pada perlakuan tanpa pupuk P. Penambahan bahan organik baik pupuk kandang maupun kompos jerami dapat mengurangi laju evaporasi dari dalam tanah. Kondisi tanaman yang tidak di pupuk P maka penambahan bahan organik dapat meningkatkan serapan hara P pada tanaman untuk tanah dengan karakteristik kandungan P potensial sedang sampai tinggi. Perlakuan kompos jerami mempunyai nilai efisiensi agronomis nitrogen mencapai 13,66.

The priority of agricultural development is to supply national food in line with the increasing population. One of the ways to enhance rice production is to apply inorganic fertilizers, but the application of inorganic fertilizer in the long term causes soil and water degradation. The organic fertilizer would restore the soil condition. This research aims to determine differences in morphology rice Inpari 33 and water use efficiency in treatments inorganic and organic fertilization. The research was conducted from July to December 2020 in IP2TP Sukamandi, Indonesian Center for Rice Research, Subang-West Java. The treatments were Split Plot Design with three replications. The main plot was inorganic fertilizers, namely no application fertilizer of NPK, N, K, P, and NPK fertilizer. Sub-plots were organic fertilizers consisting of manure, straw compost, and non-organic fertilizers. The research result showed that inorganic fertilizers increased the number of tillers by 44-49%, SPAD value 6,9-10,98%, rice production 23-51%, water use efficiency 1.17% on minus P treatment. The treatment of inorganic fertilizers did not affect the rate of photosynthesis but did affect stomatal conductance and nutrient uptake. The highest efficiency of air use was 1.17 g of L-1 grain in the treatment without P. The application of organic fertilizers had not increased growth, yield, photosynthesis and water use efficiency. The application of fertilizers can increase stomata conductance. The average consumptive water requirement of rice plants during the study was 469.48 mm, with an average evapotranspiration coefficient of 1.18. The interaction of inorganic and organic fertilizers affected the number of tillers, number of panicles per clump, weight of 1000 grains, nutrient uptake and total evapotranspiration. The addition of cow manure greatly affected the number of tillers and total evapotranspiration in the treatment without P fertilizer. The addition of organic matter, both manure and straw compost, could reduce the rate of evaporation from the soil. In the condition of plants that are not fertilized with P, organic matter can increase the uptake of P nutrients in plants for soils with moderate to high potential P content. The treatment of straw compost had an agronomic nitrogen efficiency value of 13.66.