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In Indonesia, sugarcane (Saccharum officinarum L.) is mostly cultivated in drylands, thus depending on rainfall for crop growth and development. Rainfall is an essential factor affecting sugarcane productivity. The global climate indices can be used to investigate potential of rainfall within a given area and its relationship with crop productivity. This reserach aimed to analyze the relationship between the global climate index, rainfall, and sugarcane productivity in drylands near Glenmore sugar mill, i.e., Benculuk and Jolondoro, Banyuwangi, East Java, Indonesia. The global climate index data used were the Southern Oscillation Index (SOI) and Sea Surface Temperature (SST) between 1995 and 2014. Results of this research showed that SOI and SST can be used to predict the rainfall in both Benculuk and Jolondoro. Rainfall (y) can be predicted with SST data (x) using the equation of y = -352.49x + 7724.1 in Benculuk and y = -107.32 + 3443.4 in Jolondoro, as well as with SOI data (x) using the equation of y = 38.664x + 1555.1 in Benculuk and y = 10.541x + 1567.8 in Jolondoro. Sugarcane productivity (y) in Jolondoro can be predicted using data of total rainfall (x) between October and March with the following equation: y = -0.1672x + 1157.3. This equation can be used by sugar mills, sugarcane growers, and other sugarcane-relevant stakeholders for determining the appropriate growing season.

Pengaturan kerapatan tanam pada galur harapan kapas perludilakukan agar penggunaan sumberdaya lebih efisien dan tidakmengganggu tanaman palawija yang ditumpangsarikan. Pengaturantanaman dilakukan sedemikian rupa untuk memberikan ruang tumbuhyang lebih baik terhadap pertumbuhan dan perkembangan tanaman.Penelitian kerapatan tanam galur harapan kapas pada sistem tumpangsaridengan jagung dilakukan di lahan petani di Desa Pendem, KecamatanNgaringan, Kabupaten Grobogan, Jawa Tengah pada lahan kering/tadahhujan dari bulan Desember 2002 hingga Mei 2003. Tujuan penelitianuntuk mendapatkan kerapatan tanam yang sesuai pada galur harapan kapaspada sistem tumpangsari dengan jagung. Percobaan disusun dalamrancangan petak terbagi dengan varietas sebagai petak utama dankerapatan tanaman sebagai anak petak yang diulang 3 kali dan 2 ulanganmonokultur kapas dan jagung. Sebagai petak utama adalah 3 varietas/galurkapas: 88003/16/2, 92016/6, dan Kanesia 7; dan anak petak terdiri daritiga kerapatan tanam : 2 : 2 (2 baris kapas dan 2 baris jagung); 2 : 3 (2baris kapas dan 3 baris jagung); dan 3 : 2 (3 baris kapas dan 2 barisjagung). Hasil penelitian menunjukkan bahwa kerapatan tanam yangsesuai pada galur/varietas harapan kapas adalah kerapatan tanam 3 : 2 (3baris kapas dan dua baris jagung) dengan produksi kapas 1.563,9 kg/hadan jagung 3.840,7 kg/ha. Pada kerapatan tanam tersebut, populasi kapasadalah 32.566 tanaman/ha (81% dari populasi monokultur) dan jagung38.000 tanaman/ha (72% dari monokultur). Produktivitas kapas galur92016/6 mencapai 1.583,9 kg/ha dan nyata lebih tinggi dibanding galur88003/16/2 dan Kanesia 7 pada berbagai kerapatan tanam.Kata kunci : Gossypium hirsutum, Zeamays, kerapatan tanaman,tumpangsariABSTRACTArrangement of crop densities for new cotton lines underintercropping system with maizeThe arrangement of crop densities for cotton new varieties/lines isneeded to improve the use of natural resources under intercropping systemwith maize. The field trial on different crop densities for new cotton linesunder intercropping system with maize was conducted in Grobogan,Central Java in rainy season 2002/2003. The purpose of the study was toinvestigate the optimum population for new cotton lines underintercropping with maize. The field experiment was arranged in a SplitPlot Design with three replications. Three new cotton lines/varieties wereallocated to main plots: 88003/16/2, 92016/6, and Kanesia 7. Three croparrangements were allocated to sub-plots: 2 : 2 [2 cotton rows and 2 rowsof maize]; 2 : 3 [ 2 cotton rows and 3 rows of maize] and 3:2 [ 3 cottonrows and 2 rows of maize]. Results showed that the crop arrangement forcotton and maize under intercropping system is 3 cotton rows and 2 rowsof maize, with cotton yield 1,563.9 kg/ha and maize 3,840.7 kg/ha. Cottonyield of 92016/6 is higher than those of 88003/16/2 and Kanesia 7 underthe all crop arrangement tested.Key words: Gossypium hirsutum, Zea mays, crop density, intercropping