This experiment was conducted to reveal genetic diversity among 38 genotypes of sugarcane (Saccharum officinarum L.) using RAPD markers. The population consisted of 8 genotypes from Australia, 7 from Africa, 10 from America, and 13 from Asia. Genetic similarity was ranging from 17% to 97% , with the average of 57%. UPGMA dendrograms divided the population into three major groups i.e. group 1, 2, and 3 which consisted of 23, 10, and 5 genotypes, respectively. Each major group comprised genotypes of different geographical origins. The dendrogram divided each group into some subgroups. There were 8 subgroups i.e. 4 subgroups in group 1, 2 subgroups in group 2, and 2 subgroups in group 3. Some genotypes of same geographical origin were clustered into in at least 3 different subgroups, meaning that they were genetically dissimilar. On the other hand, some other genotypes of different geographical origin were clustered into the same subgroup, meaning that they were genetically similar. This data would help sugarcane breeders to select parents for hybridization in order to maximize heterosis. This could be conducted by selecting parents of dissimilar genotypes.

Limbah domestik (greywater) sebagian besar dibuang langsung dalam badan air tanpa adanya pengolahan karena biaya yang mahal, penerapan yang sulit dan teknologi yang belum terjangkau masyarakat, sehingga dapat mencemari lingkungan. Pengolahan air limbah domestik yang efisien, murah, mudah dan ramah lingkungan harus dikembangkan. Fitoremediasi merupakan salah satu pengolahan air limbah dengan menggunakan agen biologi gulma air. Penelitian ini bertujuan untuk mengetahui efektifitas fitoremediasi menggunakan kombinasi beberapa jenis gulma air Eceng gondok (Eichhornia crassipes (Mart)), Kiambang (Salvinia molesta) dan Kayu apu (Pistia Stratiotes L.) dalam memperbaiki kualitas air limbah domestik. Rancangan percobaan yang digunakan perlakuan faktorial 8 x 2 dalam Rancangan Acak Kelompok dengan 3 ulangan. Faktor pertama adalah jenis gulma dengan 8 level yaitu tunggal, kombinasi 2 gulma dan kombinasi 3 gulma Faktor kedua adalah waktu pengamatan dengan 2 level yaitu 4 hari dan 8 hari. Parameter yang diukur adalah pH, COD, BOD, TSS, amonia dan minyak lemak. Hasil penelitian menunjukkan bahwa gulma Eceng gondok, Kiambang, Kayu apu perlakuan tunggal, kombinasi 2 jenis gulma dan kombinasi 3 jenis gulma sangat efektif dan sama baiknya dalam menaikan pH dan menurunkan COD, BOD, TSS, amonia dan minyak lemak air limbah domestik pada hari ke-4 maupun hari ke-8 sampai memenuhi baku mutu yang disyaratkan oleh kementrian Lingkungan Hidup dan Kehutanan No. 68 Tahun 2016.

This research aimed to evaluate the residual Cu and Zn in tropical soil over 21 years after amendment with industrial waste, lime, and compost. Soil samples were collected from a well-maintained experimental field amended one time with industrial waste high in Cu and Zn set in 1998 at about 1.5–20 years after amendment. Treatments were arranged in a randomized block design with a metal-wares industrial waste at rates 0, 15, and 60 Mg·ha−1, lime at 0 and 5 Mg·ha−1, and compost at 0 and 5 Mg·ha−1. Soil samples were also taken vertically in the exact plot centers at depths of 0–75 cm of plots not amended with lime and compost and also from topsoils (0–15 cm) at 90 points with distances 50 cm between each other in each of the respective plots 21 years after amendment. Significant increases in Cu and Zn caused by waste were observed over 21 years. The increase in soil pH by lime was observed over 10 years but its effect in decreasing Cu and Zn was observed only at 1.5 years, particularly in topsoils. However, the effect of lime in lowering Cu and Zn was observed over 20 years when waste and/or compost were also given. Similarly, the effect of compost was absent over 20 years but significant when waste and/or lime were also given. The relative concentration of Cu and Zn in the 60 Mg waste ha−1 plots decreased over 20 years to 17–53% for Cu and to 12–33% for Zn; their concentrations were, in general, lower with lime and/or compost addition. The relative concentrations of Cu and Zn significantly decreased over 21 years in plots with 15 or 60 Mg·ha−1 and increased in the control plots. Heavy metals moved in soil significantly through soil tillage and erosion and partially by leaching.

No abstract

Penelitian ini bertujuan untuk mengetahui dosis herbisida metil metsulfuron yang efektif mengendalikan gulma di pertanaman karet, mengetahui perubahan komposisi gulma akibat aplikasi herbisida metil metsulfuron, dan mengetahui fitotoksisitas tanaman karet setelah aplikasi herbisida metil metsulfuron. Penelitian ini dilakukan di kebun rakyat Desa Onoharjo, Kecamatan Terbanggi Besar, Kabupaten Lampung Tengah dan Laboratorium Gulma Fakultas Pertanian Universitas Lampung dimulai Desember 2017 hingga Maret 2018. Penelitian ini menggunakan rancangan acak kelompok (RAK) dengan empat ulangan dan enam perlakuan yaitu dosis herbisida metil metsulfuron 15 g/ha, 20 g/ha, 25 g/ha, 30 g/ha, penyiangan mekanis, dan kontrol. Homogenitas ragam data diuji dengan uji Bartlett, additivitas data diuji dengan uji Tukey, dan perbedaan nilai tengah perlakuan diuji dengan uji Beda Nyata Terkecil (BNT) pada taraf 5%. Hasil penelitian menunjukan herbisida metil metsulfuron dosis 15 – 30 g/ha efektif mengendalikan gulma total, gulma daun lebar, Borreria alata, dan Praxelis climatidea pada 4 – 12 MSA. Herbisida metil metsulfuron dosis 15 – 30 g/ha mengendalikan gulma rumput dan teki pada 4 – 8 MSA. Herbisida metil metsulfuron dosis 15 – 30 g/ha mengendalikan gulma Axonopus compressus, Croton hirtus, dan Ottochloa nodosa pada 4 MSA di perkebunan karet TBM. Aplikasi herbisida metil metsulfuron dosis 15 – 30 g/ha menyebabkan terjadinya perubahan komposisi gulma Borreria alata menjadi Croton hirtus pada 4 MSA, Borreria alata menjadi Axonopus compressus pada 8 MSA, dan Borreria alata menjadi Ottochloa nodosa pada 12 MSA di perkebunan karet TBM. Aplikasi herbisida metil metsulfuron dosis 15 – 30 g/ha tidak menyebabkan terjadinya keracunan terhadap tanaman karet TBM.