<p>Percobaan lapang telah dilakukan di Kebun Percobaan Pekuwon, Bojonegoro, 1992, untuk mcmpelajai sifat-sifat agronomis dan kimiawi tembakau pada berbagai waktu tanam sorgum pada sistem tumpangsai tembakau + sorgum. Percobaan disusun dalam rancangan acak kelompok dengan enam ulangan. Perlakuan terdiri dai 5 taraf waktu tanam sorgum yaitu 4 dan 2 minggu sebelum tanam tembakau, bersamaan dengan waktu tanam tembakau, 2 dan 4 minggu setelah tanam tembakau. Ukuran petak 10.8 m x 12.0 m. dengan 240 tanaman tembakau per petak dan 720 tanaman sorgum per petak. Analisis N, P, K, nikotin, dan gula beturut- turut dengan Kyeldhal, Spektrofotometi, Flamefotometi, Titrasi dengan NaOH dan Luff-Schroll. Hasil percobaan menunjukkan bahwa dengan mempcrcepat waktu tanam sorgum dari 4 minggu setelah tanam tembakau menjadi 4 minggu sebelum tanam tembakau sangat menurunkan pertumbuhan, hasil dan mutu. Scbaliknya perlakuan tersebut meningkat¬ kan kadar N-total, P, dan K, dan hasil sorgum tumpangsai, serta tidak berpengaruh pada kadar nikotin, gula, nisbah/nikotin, dan N/nikotin tembakau. Pada keadaan kering yang dialami oleh percobaan ini walaupun hasil tembakau rendah namun mutu hasil masih dalam kisaran yang baik dan persaingan dikuasai oleh tanaman sorgum.</p><p>Kata kunci: Nicotiana tabacum, sorgum bicolor, tumpangsai, waktu tanam</p><p> </p><p><strong>ABSTRACT</strong></p><p><strong>Agronomics and chemicals properties of tobacco under different planting dates ofsorghum in tobacco -Horghum intercropping system</strong></p><p>The ield expeiment was conducted at Pekuwon Expeimental Station, Bojonegoro, in 1992, to study the agronomic and chemical propeties of tobacco grown under diferent planting dates of sorghum in tobacco+sorghum intercropping system. The expeiment was arranged in randomized block design, with 6 replications. The treatment consisted of 5 levels of sorghum planting, 2 and 4 weeks ater tobacco planting. Plot size was 10.8 m x 12.0 m, with 240 and 720 plants of tobacco and sorghum respectively. The methods for analyses N, P, K, nicotine and sugar analyses were Kyeldhal, Spectrophotometry, Flame photometry, Titration with NaOH, and Luf-Schroll, respectively. The growth, yield, and quality of tobacco were decreased sharply, but the N, P, K contents of the leaves were increased by accelerating planting date of sorghum from 4 weeks ater to 4 weeks before tobacco planting. The content of nicotine, sugar, sugar/nicotine. N/nicotine of the leaves were not afected by this treatment. In dry condition, although the yield of tobacco was low, but the quality was in good category, and the competition in tobacco ♦ sorghum intercropping system was dominated by sorghum.</p><p>Key words : Nicotiana tabacum, sorghum bicolor, intercropping, planting date</p>