PENINGKATAN “ESTABLISHMENT RATE” TANAMAN KEDELAI DAN KACANG HIJAU DENGAN APLIKASI BEBERAPA BAHAN PEMBENAH TANAH PADA BEDENG DI LAHAN VERTISOL TADAH HUJAN LOMBOK SELATAN IMPROVEMENT OF CROP ESTABLISHMENT RATES OF SOYBEAN AND A SUBSEQUENT MUNGBEAN THROUGH THE APPLICATION OF SEVERAL TYPES OF SOIL AMENDMENT ON RAISED-BEDS ON RAINFED VERTISOLS OF SOUTHERN LOMBOK

Abstract

ABSTRAK

Penelitian bertujuan untuk mengetahui pengaruh aplikasi bahan pembenah tanah pada bedeng di lahan vertisol Lombok Selatan terhadap pertumbuhan (crop establishment) dan hasil biji tanaman kedelai yang ditanam pada MK1 dan tanaman kacang hijau pada MK2 yang ditugal langsung setelah panen kedelai MK1. Percobaan dilaksanakan di lahan sawah tadah hujan milik petani di desa Mujur (Lombok Tengah), dari bulan Juni sampai dengan Nopember 2011, yang ditata menurut Rancangan Acak Kelompok, dengan 3 blok dan 6 perlakuan, yaitu tanpa bahan pembenah tanah (P0), aplikasi bahan pembenah tanah berupa pasir (P1), pupuk kandang (pukan) sapi (P2), Bokashi (P3), pasir + pukan (P4), dan pasir + Bokashi (P5). Analisis data dilakukan dengan ANOVA (Analysis of Variance) menggunakan teknik kontras-ortogonal pada taraf nyata 5%. Hasil penelitian menunjukkan bahwa aplikasi bahan pembenah tanah pada bedeng permanen di lahan vertisol tadah hujan Lombok Selatan secara nyata meningkatkan establishment rate dan hasil biji tanaman kedelai dan kacang hijau. Bahkan hanya dengan aplikasi pasir (P1), yang dicampur dengan lapisan atas tanah pada bedeng, dapat dicapai crop establishment dan hasil biji yang lebih tinggi, dengan rata-rata hasil 1,9 ton/ha biji kedelai dan 1,96 ton/ha biji kacang hijau, jika dibandingkan dengan bedeng tanpa bahan pembenah tanah (P0), dengan rata-rata hasil 1,1 ton/ha biji kedelai dan 0,29 ton/ha biji kacang hijau, padahal secara jangka panjang, pasir tidak akan hilang karena tidak diserap oleh tanaman. Hasil tertinggi diperoleh pada perlakuan aplikasi pasir dan Bokashi (P5), dengan rata-rata hasil 2,5 ton/ha biji kedelai dan 3,43 ton/ha biji kacang hijau.

ABSTRACT

The study aimed to examine the effect of application of soil amendment materials on raised-beds of Southern Lombok vertisol land on growth (crop establishment) and seed yield of soybean plants grown in MK1 (dry season 1) and MK2 mungbean plants direct dibbled immediately after harvest of the MK1 soybean. The experiment was conducted on a rainfed ricefield owned by a farmer in the Mujur village (Central Lombok), from June to November 2011, which was designed according to the Randomized Complete Block Design, with 3 blocks and 6 treatments, i.e. without soil amendment (P0), the application of sand (P1), cattle manure (P2), Bokashi (P3), sand + manure (P4), and sand + Bokashi (P5). Data were analyzed using ANOVA (Analysis of Variance) based on the contrast-orthogonal technique at 5% level of significance. The results indicated that application of soil amendment materials on the raised-beds, in the southern Lombok rainfed vertisol land, significantly increased the establishment rate and seed yield of soybean in MK1 (dry season 1) and mungbean in MK2 (dry season 2), which was direct dibbled immediately after harvest of the MK1 soybean. Even with the application of sand only, by mixing it with the top soil layer of the raised-beds, better crop establishment and higher seed yields were achieved, with an average of 1.9 ton/ha soybean seeds and 1.96 ton/ha mungbean seeds, compared with an average of only 1.1 ton/ha soybean seeds and 0.29 ton/ha mungbean seeds obtained from the plots without application of amendment materials, while in fact in the long term, the sand will not be disappear because it is not absorbed by plants. The highest yield was obtained from the plot with application of both sand and Bokashi (P5), with an average of 2.5 ton/ha soybean seeds and 3.43 ton/ha mungbean seeds.