Judul: Physiological characteristic of local upland rice from Southwest Sumba Regency under various drought stress conditions
Abstrak: Cekaman kekeringan merupakan salah satu faktor abiotik yang sangat berpengaruh terhadap produktivitas padi. Besarnya penurunan hasil panen akibat cekaman kekeringan dipengaruhi oleh tingkat kepekaan varietas. Penelitian ini bertujuan mengetahui pengaruh berbagai perlakuan cekaman kekeringan terhadap respons fisiologi tumbuhan padi gogo lokal (Gogo Wangi) asal Kabupaten Sumba Barat Daya. Padi Gogo Wangi diberi perlakuan cekaman kekeringan dengan penyiraman 1/2 Kapasitas Lapang (KL) dan 1/4 KL. Sebagai kontrol, padi Gogo Wangi diberi penyiraman dengan 1 KL. Parameter yang diamati adalah komponen karakter vegetatif dan reproduktif, kadar air relatif (KAR), kadar prolin, dan kandungan asam askorbat (ASA) daun. Hasil menunjukkan bahwa cekaman kekeringan menurunkan nilai KAR daun yang berakibat kadar prolin dan kandungan ASA daun meningkat. Cekaman kekeringan juga mempengaruhi tinggi dan bobot kering tajuk, panjang dan bobot kering akar, serta umur berbunga dan panen kedua varietas padi. Namun, cekaman kekeringan tidak mempengaruhi jumlah anakan per rumpun, jumlah daun, jumlah anakan produktif, panjang malai, dan jumlah biji per malai., Drought stress is one of the abiotic factors that decreasing of upland rice productivity. The decreased crop due to drought stress is affected by sensibility level of varieties. The objective of the study was to evaluate physiological responses of local upland rice (Gogo Wangi) from Southwest Sumba Regency under various drought stress conditions. The condition treatments consisted of control with 1 Land Capacity (LC), 1/2 LC, and 1/4 LC watering volume. Observed parameters were vegetative and reproductive characters, leaves relative water content (RWC), proline, and ascorbic acid density. The results showed that drought stress decreased the value of RWC leaves resulting levels of proline and ascorbic acid in leaves increased. Drought stress also significantly affected canopy height and dry weight, root length and dry weight, and days to flower and harvest of two rice varieties. However, drought stress did not affect number of tillers per hill, number of leaves, number of productive tillers, panicle length and number of grains per panicle. Keyword: ascorbic acid, drought stress, local upland rice, proline, Sumba
Keyword: asam askorbat, padi gogo lokal, kekeringan, prolin, Sumba

Judul: Studi Karakter Morfologi dan Fisiologi yang Berkaitan dengan Efisiensi Pemakaian Air Varietas Padi Gogo
Abstrak: The demand for food consumption of rice increased with the increasing population, while recently wetland experiencing a great reduction. Therefore, dry land cultivation has been developed, including cultivation of upland rice. Dry land crop management in general is constrained by the availability of water, because source of water are only the rain and the soil's ability to retain water. Upland rice cultivation required specific cultivation, particularly the use of crop varieties that have good water-use efficiency or varieties of plants that are able to adapt to the conditions of limited water availability. Research on morphological and physiological studies related to water use efficiency of upland rice varieties need to be developed in order to create optimum utilization of dry land. The research was conducted from October 2013 to April 2014 in the greenhouse IPB Experimental Station Cikabayan, Bogor. The research design was arranged in factorial experiment and using a randomized block design. The first factor was 5 upland rice varieties (Inpago 5, Batutegi, Jatiluhur, Inpago 8 and Sarinah). The second factor was 4 irrigation intervals which were 3, 6, 9, and 12 days. Thus there are 20 combinations of treatment. Each treatment was repeated 3 times and each experimental unit consisted of 3 media so that overall there are 180 growing media. Each planting medium consisted of three plant sample (one family). Plants in polythene bags are used as destructive plants, and were observed at the time of entry phase of the vegetatife phase and the generative phase based on the characteristics of each variety. Plants in buckets are used for the measurement of growth until the generative phase. Characteristics that assosiated with water saving of upland rices were higher plant height, longer panicle, larger roots volume, narrower leaves, higher evapotranspiration, faster flowering phase, greener leaves, higher number of leaves and tillers, heavier dry matter, higher number of grains, heavier 100 grain weight and dry weight of grains. The fraction of available absorbed water at panicle inisiation, flowering inisiation and harvesting phase was 83.36%, 137.14% and 116.65%, respectively, to obtain dry grains of 3.39 ton ha-1. Productivity of each variety at intervals of 3 days irrigation was 3.80 ton ha-1 (Inpago 5), 3.27 ton ha-1 (Batutegi), 3.86 ton ha-1 (Jatiluhur), 3.91 ton ha-1 (Inpago 8) and 2.12 ton ha-1 (Sarinah).
Keyword: Batutegi, evapotranspiration, productivity, water fraction

Judul: Desain Sistem Transfer Energi Nirkabel Berbasiskan Tesla Coil
Abstrak: Tesla coil merupakan alat yang ditemukan oleh Nikola Tesla yang dapat mentransmisikan daya tanpa kabel dengan memanfaatkan prinsip induksi elektromagnetik. Pada penelitian ini dibuat sebuah prototype Tesla Coil dengan menggunakan transistor C1970 dan receiver menggunakan rangkaian LC. Identifikasi alat meliputi pengaruh daya input transmitter terhadap receiver, bentuk signal yang dipancarkan transmitter, pengaruh jarak transmitter dan receiver, nilai efisiensi serta efek alat terhadap perangkat lain. Hasil pengamatan menunjukkan bahwa semakin besar daya input maka semakin besar daya yang dipancarkan oleh transmitter. Bentuk sinyal yang dipancarkan oleh transmitter berupa gelombang listrik AC sinusoidal dengan frekuensi ~2.9 MHz. Semakin jauh jarak receiver terhadap transmitter maka semakin kecil amplitudo gelombang AC yang diterima oleh receiver, menyebabkan semakin kecil daya yang diterima oleh receiver. Adapun nilai efisiensi terbesar penangkapan daya oleh receiver yaitu sebesar 0.00516 % serta terdapat gangguan pada alat-alat tertentu seperti monitor komputer dan radio.
Keyword: rangkaian LC, receiver, tesla coil, transistor C1970, transmitter