Perubahan Komposisi Gulma pada Sistem Tumpangsari Padi Gogo dengan Kedelai di Lahan Pasir Pantai

Weeds can reduce upland rice yields in coastal sandy area. Density and growth of weeds can be controlled and reduced by an intercropping system between upland rice with soybeans. The study aimed to determine the weeds composition change and weeds biomass in various crop proportions of upland rice and soybean under intercropping. The research was conducted from December 2016 until March 2017, at coastal sandy soil of Samas, Bantul, Yogyakarta (8°00\u2703.5”S and 110°15\u2720.1”E). This study used a complete randomized block design (RCBD) with one factor and three replications. The treatments were crop proportions of upland rice and soybean under intercropping with 6 levels, such as 100:0 (upland rice monoculture), 80:20, 60:40, 40:60, 20:80, and 0: 100 (soybean monoculture). The results showed that there was weeds composition changes due to setting crop proportions of upland rice and soybean under intercropping at coastal sandy soil. Weed of sedges, grass, and broadleaf were found throughout the experimental plots, but varied in number and type of weeds among experimental plots. Weeds condition differed among the soybean proportion treatments < 40% and ≥ 40%. The average community coefficient value was <75% which was dominated by Digitaria nuda and Eragrostis tenella under soybean proportion treatments < 40%, and Ludwigia parviflora and Amaranthus lividus under soybean proportion treatments ≥ 40%. The linear model was established between the increase of soybean proportion to a decrease in dry weight of weeds as Y = -0.6624X + 67.699; R2 = 0.7224)

Permeabilitas dan Perkecambahan Benih Aren (Arenga Pinnata (Wurmb.) Merr.)

The characteristics of seed coat delay the germination of sugar palm seeds. A research was carried out to investigate the permeability of sugar palm seeds and accelerate the germination. The research consists of four experiments with purposes: 1. to investigate the distribution of water content of sugar palm seed (RCBD Factorial between part of seed : whole seed, seed coat, endosperm and embryo under three conditions: control; soaking in water and germinate, 5 replications); 2. to investigate seed permeability (RCD, 6 soaking periods, 4 replications); 3. to investigate the content of lignin and tannin in seed (RCD, 8 seed ages, 4 replications); 4. to accelerate seed germination (RCBD, 6 treatments of scarification, 4 replication). The results showed that the permeability of sugar palm seeds to water absorption declined with seed maturity because of the increasing in lignin and tannin content. Seed germination can be accelerated with scalding on the operculum site to increase water absorption

Effect of Acetic Acid as Pre-Emergence Herbicide on Maize Germination

Profitable crop production starts with a weed control program that includes pre-emergence herbicides to deliver long-lasting, residual weed control. Pre-emergence herbicides are applied to prevent the germination of weed seeds. The study was conducted to determine the effect of acetic acid as a pre-emergence herbicide on maize germination. Pots experiment was conducted on August until September 2012. The experimental design used was Completely Randomized Design (CRD) single factor in four replicates. The application of pre-emergence acetic acid at several concentration, i.e. control (no acetic acid) 0%, 10% acetic acid and 20% acetic acid. The result showed that the pre-emergence aplication at 10% and 20% of the glacial acetic acid solution lowered pH were 5,12 and 5,43 respectively at one week after application, so that inhibited maize germination. No shoots and roots were grew. This was due to the increase of electrical conductivity (EC) or electrolyte leakage caused by the high permeability of the damaged membrane of seed. The EC of control treatment was 11μS/cm g, compared to 10 and 20% treatment of acetic acid were 36 μS / cm g and 55 μS / cm g EC respectively. Increasing concentration of acetic acid caused the higher of protein content leaked, i.e. 7,95%, 7,32% and 7,03% respectively for without acetic acid treatment, 10% and 20% acetic acid. Acetic acid also inhibited respiration rate of maize seed, where the higher concentration of acetic acid produced the lower respiration rate, i.e. 31.63 mg/g/hour, 12.38 mg/g/hour and 2,75 mg/g/hour respectively for without acetic acid treatment, 10% and 20% acetic acid

Identifikasi Sifat Benih Kawista (Feronia Limonia (L.) Swingle) Untuk Tujuan Penyimpanan

Penanganan benih yang tepat dapat mempertahankan mutu benih selama penyimpanan atau dapat menekan laju kemunduran benih seminimal mungkin. Dalam terminologi penanganan benih terdapat tiga kelompok benih yaitu benih ortodoks, rekalsitran dan intermediate. Sampai saat ini belum diketahui apakah benih kawista masuk dalam kelompok ortodoks, rekalsitran atau intermediate sehingga dalam rangka untuk mempertahankan viabilitasnya selama dalam penyimpanan perlu dilakukan identifikasi sifat benih kawista. Tujuan penelitian adalah mengidentifikasi sifat benih kawista untuk tujuan penyimpanan. Benih kawista yang digunakan berasal dari Desa Dasun, Kecamatan Lasem, Kabupaten Rembang. Pengujian sifat benih dengan menggunakan metode yang dikemukakan Hong & Ellis (1996). Selain itu juga dilakukan pengamatan terhadap bobot kering dan kadar air benih selama perkembangan benih mulai dari antesis sampai benih masak. Hasil penelitian menunjukkan benih kawista termasuk dalam kriteria benih ortodoks, karena tetap menunjukkan viabilitas yang tinggi yang ditunjukkan oleh persentase perkecambahan yang tetap tinggi dan tidak berbeda nyata pada beberapa tingkat kadar air. Persentase perkecambahan berkisar antara 96,0-98,5% pada semua kadar air, yaitu kadar air 40,6% (kadar air setelah ekstraksi); 10,5% dan 5,5% (baik sebelum maupun setelah disimpan tiga bulan pada suhu -20 0C) dengan bobot kering kecambah yang tidak berbeda nyata

Identifikasi Sifat Benih Kawista (Feronia Limonia (L.) Swingle) Untuk Tujuan Penyimpanan

Penanganan benih yang tepat dapat mempertahankan mutu benih selama penyimpanan atau dapat menekan laju kemunduran benih seminimal mungkin. Dalam terminologi penanganan benih terdapat tiga kelompok benih yaitu benih ortodoks, rekalsitran dan intermediate. Sampai saat ini belum diketahui apakah benih kawista masuk dalam kelompok ortodoks, rekalsitran atau intermediate sehingga dalam rangka untuk mempertahankan viabilitasnya selama dalam penyimpanan perlu dilakukan identifikasi sifat benih kawista. Tujuan penelitian adalah mengidentifikasi sifat benih kawista untuk tujuan penyimpanan. Benih kawista yang digunakan berasal dari Desa Dasun, Kecamatan Lasem, Kabupaten Rembang. Pengujian sifat benih dengan menggunakan metode yang dikemukakan Hong & Ellis (1996). Selain itu juga dilakukan pengamatan terhadap bobot kering dan kadar air benih selama perkembangan benih mulai dari antesis sampai benih masak. Hasil penelitian menunjukkan benih kawista termasuk dalam kriteria benih ortodoks, karena tetap menunjukkan viabilitas yang tinggi yang ditunjukkan oleh persentase perkecambahan yang tetap tinggi dan tidak berbeda nyata pada beberapa tingkat kadar air. Persentase perkecambahan berkisar antara 96,0-98,5% pada semua kadar air, yaitu kadar air 40,6% (kadar air setelah ekstraksi); 10,5% dan 5,5% (baik sebelum maupun setelah disimpan tiga bulan pada suhu -20 0C) dengan bobot kering kecambah yang tidak berbeda nyata

Incidence of Soybean Mosaic Disease in East Java Province

The objectives of this study were: 1) to identify the mosaic symptom severity and the incidence the virus and relate these to soybean yield reduction is four regions of East Java; 2) diagnostic of the symptom using Indirect ELISA, RT-PCR and electron microscope observation. Results from experiments indicated that soybean plants infected with SMV and CMMV, alone or in combination produced mosaic symptom. Incidence of the virus, as judged by symptomatology, ranged from mild to severe infection the percentage of plants being from 13.42-30.10%. Soybean plants with mosaic symptom caused SMV from an early stage of development (14-28 days after planting). Soybean mosaic virus belongs to the virus family Potyviridae. Specific DNA fragment of 1687 bp was successfully amplified from soybean infected by SMV isolate Ngawi, Madiun, Magetan, and Ponorogo. Specific DNA fragment of 1385 bp was successfully amplified from SMV by CI coding region. The mosaic symptom on soybean plant (28-42 days after planting) caused CMMV. Flexious virus particle 650 nm in length was observed on electron microscope. It caused local lesions on Chenopodium amaranticolor, but not detected by I ELISA with antiserum SMV and RT-PCR with universal primer